Merge remote-tracking branch 'origin/master' into glob_outdir_bug

.gitignore

@@ -9,12 +9,14 @@ test-args.txt
 \#*\#
 .\#*
 tests/baselines/local/*
+tests/baselines/local.old/*
 tests/services/baselines/local/*
 tests/baselines/prototyping/local/*
 tests/baselines/rwc/*
 tests/baselines/test262/*
 tests/baselines/reference/projectOutput/*
 tests/baselines/local/projectOutput/*
+tests/baselines/reference/testresults.tap
 tests/services/baselines/prototyping/local/*
 tests/services/browser/typescriptServices.js
 scripts/authors.js

Jakefile.js

@@ -64,7 +64,20 @@ var compilerSources = [
     "utilities.ts",
     "binder.ts",
     "checker.ts",
+    "factory.ts",
+    "visitor.ts",
+    "transformers/destructuring.ts",
+    "transformers/ts.ts",
+    "transformers/module/es6.ts",
+    "transformers/module/system.ts",
+    "transformers/module/module.ts",
+    "transformers/jsx.ts",
+    "transformers/es7.ts",
+    "transformers/generators.ts",
+    "transformers/es6.ts",
+    "transformer.ts",
     "sourcemap.ts",
+    "comments.ts",
     "declarationEmitter.ts",
     "emitter.ts",
     "program.ts",
@@ -85,7 +98,20 @@ var servicesSources = [
     "utilities.ts",
     "binder.ts",
     "checker.ts",
+    "factory.ts",
+    "visitor.ts",
+    "transformers/destructuring.ts",
+    "transformers/ts.ts",
+    "transformers/module/es6.ts",
+    "transformers/module/system.ts",
+    "transformers/module/module.ts",
+    "transformers/jsx.ts",
+    "transformers/es7.ts",
+    "transformers/generators.ts",
+    "transformers/es6.ts",
+    "transformer.ts",
     "sourcemap.ts",
+    "comments.ts",
     "declarationEmitter.ts",
     "emitter.ts",
     "program.ts",
@@ -102,6 +128,7 @@ var servicesSources = [
     "services.ts",
     "shims.ts",
     "signatureHelp.ts",
+    "types.ts",
     "utilities.ts",
     "formatting/formatting.ts",
     "formatting/formattingContext.ts",
@@ -307,7 +334,10 @@ var builtLocalCompiler = path.join(builtLocalDirectory, compilerFilename);
     * @param callback: a function to execute after the compilation process ends
     */
 function compileFile(outFile, sources, prereqs, prefixes, useBuiltCompiler, opts, callback) {
-    file(outFile, prereqs, function () {
+    file(outFile, prereqs, function() {
+        if (process.env.USE_TRANSFORMS === "false") {
+            useBuiltCompiler = false;
+        }
         var startCompileTime = mark();
         opts = opts || {};
         var compilerPath = useBuiltCompiler ? builtLocalCompiler : LKGCompiler;
@@ -745,8 +775,14 @@ function cleanTestDirs() {
 }
 
 // used to pass data from jake command line directly to run.js
-function writeTestConfigFile(tests, light, taskConfigsFolder, workerCount) {
-    var testConfigContents = JSON.stringify({ test: tests ? [tests] : undefined, light: light, workerCount: workerCount, taskConfigsFolder: taskConfigsFolder });
+function writeTestConfigFile(tests, light, taskConfigsFolder, workerCount, stackTraceLimit) {
+    var testConfigContents = JSON.stringify({ 
+        test: tests ? [tests] : undefined,
+        light: light,
+        workerCount: workerCount,
+        taskConfigsFolder: taskConfigsFolder,
+        stackTraceLimit: stackTraceLimit
+    });
     fs.writeFileSync('test.config', testConfigContents);
 }
 
@@ -757,10 +793,15 @@ function deleteTemporaryProjectOutput() {
 }
 
 function runConsoleTests(defaultReporter, runInParallel) {
-    cleanTestDirs();
+    var dirty = process.env.dirty;
+    if (!dirty) {
+        cleanTestDirs();
+    }
+
     var debug = process.env.debug || process.env.d;
     tests = process.env.test || process.env.tests || process.env.t;
     var light = process.env.light || false;
+    var stackTraceLimit = process.env.stackTraceLimit;
     var testConfigFile = 'test.config';
     if (fs.existsSync(testConfigFile)) {
         fs.unlinkSync(testConfigFile);
@@ -780,7 +821,7 @@ function runConsoleTests(defaultReporter, runInParallel) {
     }
 
     if (tests || light || taskConfigsFolder) {
-        writeTestConfigFile(tests, light, taskConfigsFolder, workerCount);
+        writeTestConfigFile(tests, light, taskConfigsFolder, workerCount, stackTraceLimit);
     }
 
     if (tests && tests.toLocaleLowerCase() === "rwc") {
@@ -849,7 +890,7 @@ function runConsoleTests(defaultReporter, runInParallel) {
         }
     }
     function runLinter() {
-        if (!lintFlag) {
+        if (!lintFlag || dirty) {
             return;
         }
         var lint = jake.Task['lint'];
@@ -866,8 +907,8 @@ task("runtests-parallel", ["build-rules", "tests", builtLocalDirectory], functio
     runConsoleTests('min', /*runInParallel*/ true);
 }, { async: true });
 
-desc("Runs the tests using the built run.js file. Optional arguments are: t[ests]=regex r[eporter]=[list|spec|json|<more>] d[ebug]=true color[s]=false lint=true bail=false.");
-task("runtests", ["build-rules", "tests", builtLocalDirectory], function () {
+desc("Runs the tests using the built run.js file. Optional arguments are: t[ests]=regex r[eporter]=[list|spec|json|<more>] d[ebug]=true color[s]=false lint=true bail=false dirty=false.");
+task("runtests", ["build-rules", "tests", builtLocalDirectory], function() {
     runConsoleTests('mocha-fivemat-progress-reporter', /*runInParallel*/ false);
 }, { async: true });
 
@@ -884,8 +925,8 @@ var nodeServerInFile = "tests/webTestServer.ts";
 compileFile(nodeServerOutFile, [nodeServerInFile], [builtLocalDirectory, tscFile], [], /*useBuiltCompiler:*/ true, { noOutFile: true });
 
 desc("Runs browserify on run.js to produce a file suitable for running tests in the browser");
-task("browserify", ["tests", builtLocalDirectory, nodeServerOutFile], function () {
-    var cmd = 'browserify built/local/run.js -d -o built/local/bundle.js';
+task("browserify", ["tests", builtLocalDirectory, nodeServerOutFile], function() {
+    var cmd = 'browserify built/local/run.js -t ./scripts/browserify-optional -d -o built/local/bundle.js';
     exec(cmd);
 }, { async: true });
 

lib/tsc.js

@@ -825,17 +825,10 @@ var ts;
         return true;
     }
     ts.containsPath = containsPath;
-    function startsWith(str, prefix) {
-        return str.lastIndexOf(prefix, 0) === 0;
-    }
-    ts.startsWith = startsWith;
-    function endsWith(str, suffix) {
-        var expectedPos = str.length - suffix.length;
-        return expectedPos >= 0 && str.indexOf(suffix, expectedPos) === expectedPos;
-    }
-    ts.endsWith = endsWith;
     function fileExtensionIs(path, extension) {
-        return path.length > extension.length && endsWith(path, extension);
+        var pathLen = path.length;
+        var extLen = extension.length;
+        return pathLen > extLen && path.substr(pathLen - extLen, extLen) === extension;
     }
     ts.fileExtensionIs = fileExtensionIs;
     function fileExtensionIsAny(path, extensions) {
@@ -1100,8 +1093,6 @@ var ts;
     }
     ts.objectAllocator = {
         getNodeConstructor: function () { return Node; },
-        getTokenConstructor: function () { return Node; },
-        getIdentifierConstructor: function () { return Node; },
         getSourceFileConstructor: function () { return Node; },
         getSymbolConstructor: function () { return Symbol; },
         getTypeConstructor: function () { return Type; },
@@ -1233,7 +1224,7 @@ var ts;
             function readDirectory(path, extensions, excludes, includes) {
                 return ts.matchFiles(path, extensions, excludes, includes, false, shell.CurrentDirectory, getAccessibleFileSystemEntries);
             }
-            var wscriptSystem = {
+            return {
                 args: args,
                 newLine: "\r\n",
                 useCaseSensitiveFileNames: false,
@@ -1252,7 +1243,7 @@ var ts;
                     return fso.FolderExists(path);
                 },
                 createDirectory: function (directoryName) {
-                    if (!wscriptSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         fso.CreateFolder(directoryName);
                     }
                 },
@@ -1272,7 +1263,6 @@ var ts;
                     }
                 }
             };
-            return wscriptSystem;
         }
         function getNodeSystem() {
             var _fs = require("fs");
@@ -1445,7 +1435,7 @@ var ts;
             function getDirectories(path) {
                 return ts.filter(_fs.readdirSync(path), function (p) { return fileSystemEntryExists(ts.combinePaths(path, p), 1); });
             }
-            var nodeSystem = {
+            return {
                 args: process.argv.slice(2),
                 newLine: _os.EOL,
                 useCaseSensitiveFileNames: useCaseSensitiveFileNames,
@@ -1495,7 +1485,7 @@ var ts;
                 fileExists: fileExists,
                 directoryExists: directoryExists,
                 createDirectory: function (directoryName) {
-                    if (!nodeSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         _fs.mkdirSync(directoryName);
                     }
                 },
@@ -1543,7 +1533,6 @@ var ts;
                     return _fs.realpathSync(path);
                 }
             };
-            return nodeSystem;
         }
         function getChakraSystem() {
             var realpath = ChakraHost.realpath && (function (path) { return ChakraHost.realpath(path); });
@@ -2293,8 +2282,8 @@ var ts;
         Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system: { code: 6131, category: ts.DiagnosticCategory.Error, key: "Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system_6131", message: "Cannot compile modules using option '{0}' unless the '--module' flag is 'amd' or 'system'." },
         File_name_0_has_a_1_extension_stripping_it: { code: 6132, category: ts.DiagnosticCategory.Message, key: "File_name_0_has_a_1_extension_stripping_it_6132", message: "File name '{0}' has a '{1}' extension - stripping it" },
         _0_is_declared_but_never_used: { code: 6133, category: ts.DiagnosticCategory.Error, key: "_0_is_declared_but_never_used_6133", message: "'{0}' is declared but never used." },
-        Report_errors_on_unused_locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_locals_6134", message: "Report errors on unused locals." },
-        Report_errors_on_unused_parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_parameters_6135", message: "Report errors on unused parameters." },
+        Report_Errors_on_Unused_Locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Locals_6134", message: "Report Errors on Unused Locals." },
+        Report_Errors_on_Unused_Parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Parameters_6135", message: "Report Errors on Unused Parameters." },
         The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files: { code: 6136, category: ts.DiagnosticCategory.Message, key: "The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files_6136", message: "The maximum dependency depth to search under node_modules and load JavaScript files" },
         No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0: { code: 6137, category: ts.DiagnosticCategory.Message, key: "No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0_6137", message: "No types specified in 'package.json' but 'allowJs' is set, so returning 'main' value of '{0}'" },
         Variable_0_implicitly_has_an_1_type: { code: 7005, category: ts.DiagnosticCategory.Error, key: "Variable_0_implicitly_has_an_1_type_7005", message: "Variable '{0}' implicitly has an '{1}' type." },
@@ -4847,7 +4836,7 @@ var ts;
     }
     ts.isExpression = isExpression;
     function isExternalModuleNameRelative(moduleName) {
-        return /^\.\.?($|[\\/])/.test(moduleName);
+        return moduleName.substr(0, 2) === "./" || moduleName.substr(0, 3) === "../" || moduleName.substr(0, 2) === ".\\" || moduleName.substr(0, 3) === "..\\";
     }
     ts.isExternalModuleNameRelative = isExternalModuleNameRelative;
     function isInstantiatedModule(node, preserveConstEnums) {
@@ -6355,24 +6344,25 @@ var ts;
         return node.flags & 92 && node.parent.kind === 148 && ts.isClassLike(node.parent.parent);
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
+    function startsWith(str, prefix) {
+        return str.lastIndexOf(prefix, 0) === 0;
+    }
+    ts.startsWith = startsWith;
+    function endsWith(str, suffix) {
+        var expectedPos = str.length - suffix.length;
+        return str.indexOf(suffix, expectedPos) === expectedPos;
+    }
+    ts.endsWith = endsWith;
 })(ts || (ts = {}));
 var ts;
 (function (ts) {
     ts.parseTime = 0;
     var NodeConstructor;
-    var TokenConstructor;
-    var IdentifierConstructor;
     var SourceFileConstructor;
     function createNode(kind, pos, end) {
         if (kind === 256) {
             return new (SourceFileConstructor || (SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor()))(kind, pos, end);
         }
-        else if (kind === 69) {
-            return new (IdentifierConstructor || (IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor()))(kind, pos, end);
-        }
-        else if (kind < 139) {
-            return new (TokenConstructor || (TokenConstructor = ts.objectAllocator.getTokenConstructor()))(kind, pos, end);
-        }
         else {
             return new (NodeConstructor || (NodeConstructor = ts.objectAllocator.getNodeConstructor()))(kind, pos, end);
         }
@@ -6795,8 +6785,6 @@ var ts;
         var scanner = ts.createScanner(2, true);
         var disallowInAndDecoratorContext = 4194304 | 16777216;
         var NodeConstructor;
-        var TokenConstructor;
-        var IdentifierConstructor;
         var SourceFileConstructor;
         var sourceFile;
         var parseDiagnostics;
@@ -6822,8 +6810,6 @@ var ts;
         }
         function initializeState(fileName, _sourceText, languageVersion, _syntaxCursor, scriptKind) {
             NodeConstructor = ts.objectAllocator.getNodeConstructor();
-            TokenConstructor = ts.objectAllocator.getTokenConstructor();
-            IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor();
             SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor();
             sourceText = _sourceText;
             syntaxCursor = _syntaxCursor;
@@ -7130,9 +7116,7 @@ var ts;
             if (!(pos >= 0)) {
                 pos = scanner.getStartPos();
             }
-            return kind >= 139 ? new NodeConstructor(kind, pos, pos) :
-                kind === 69 ? new IdentifierConstructor(kind, pos, pos) :
-                    new TokenConstructor(kind, pos, pos);
+            return new NodeConstructor(kind, pos, pos);
         }
         function finishNode(node, end) {
             node.end = end === undefined ? scanner.getStartPos() : end;
@@ -10908,9 +10892,6 @@ var ts;
                                 case 55:
                                     if (canParseTag) {
                                         parentTagTerminated = !tryParseChildTag(jsDocTypeLiteral);
-                                        if (!parentTagTerminated) {
-                                            resumePos = scanner.getStartPos();
-                                        }
                                     }
                                     seenAsterisk = false;
                                     break;
@@ -15437,18 +15418,17 @@ var ts;
                 if (declaration.kind === 235) {
                     return links.type = checkExpression(declaration.expression);
                 }
-                if (declaration.flags & 134217728 && declaration.kind === 280 && declaration.typeExpression) {
-                    return links.type = getTypeFromTypeNode(declaration.typeExpression.type);
-                }
                 if (!pushTypeResolution(symbol, 0)) {
                     return unknownType;
                 }
                 var type = undefined;
-                if (declaration.kind === 187 ||
-                    declaration.kind === 172 && declaration.parent.kind === 187) {
-                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return decl.kind === 187 ?
-                        checkExpressionCached(decl.right) :
-                        checkExpressionCached(decl.parent.right); }));
+                if (declaration.kind === 187) {
+                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return checkExpressionCached(decl.right); }));
+                }
+                else if (declaration.kind === 172) {
+                    if (declaration.parent.kind === 187) {
+                        type = checkExpressionCached(declaration.parent.right);
+                    }
                 }
                 if (type === undefined) {
                     type = getWidenedTypeForVariableLikeDeclaration(declaration, true);
@@ -21955,7 +21935,7 @@ var ts;
         function getInferredClassType(symbol) {
             var links = getSymbolLinks(symbol);
             if (!links.inferredClassType) {
-                links.inferredClassType = createAnonymousType(symbol, symbol.members, emptyArray, emptyArray, undefined, undefined);
+                links.inferredClassType = createAnonymousType(undefined, symbol.members, emptyArray, emptyArray, undefined, undefined);
             }
             return links.inferredClassType;
         }
@@ -23175,7 +23155,7 @@ var ts;
                         checkAsyncFunctionReturnType(node);
                     }
                 }
-                if (noUnusedIdentifiers && !node.body) {
+                if (!node.body) {
                     checkUnusedTypeParameters(node);
                 }
             }
@@ -24071,7 +24051,6 @@ var ts;
                                 var parameter = local_1.valueDeclaration;
                                 if (compilerOptions.noUnusedParameters &&
                                     !ts.isParameterPropertyDeclaration(parameter) &&
-                                    !parameterIsThisKeyword(parameter) &&
                                     !parameterNameStartsWithUnderscore(parameter)) {
                                     error(local_1.valueDeclaration.name, ts.Diagnostics._0_is_declared_but_never_used, local_1.name);
                                 }
@@ -24087,9 +24066,6 @@ var ts;
                 }
             }
         }
-        function parameterIsThisKeyword(parameter) {
-            return parameter.name && parameter.name.originalKeywordKind === 97;
-        }
         function parameterNameStartsWithUnderscore(parameter) {
             return parameter.name && parameter.name.kind === 69 && parameter.name.text.charCodeAt(0) === 95;
         }
@@ -24118,14 +24094,9 @@ var ts;
         function checkUnusedTypeParameters(node) {
             if (compilerOptions.noUnusedLocals && !ts.isInAmbientContext(node)) {
                 if (node.typeParameters) {
-                    var symbol = getSymbolOfNode(node);
-                    var lastDeclaration = symbol && symbol.declarations && ts.lastOrUndefined(symbol.declarations);
-                    if (lastDeclaration !== node) {
-                        return;
-                    }
                     for (var _i = 0, _a = node.typeParameters; _i < _a.length; _i++) {
                         var typeParameter = _a[_i];
-                        if (!getMergedSymbol(typeParameter.symbol).isReferenced) {
+                        if (!typeParameter.symbol.isReferenced) {
                             error(typeParameter.name, ts.Diagnostics._0_is_declared_but_never_used, typeParameter.symbol.name);
                         }
                     }
@@ -25202,7 +25173,7 @@ var ts;
             ts.forEach(node.members, checkSourceElement);
             if (produceDiagnostics) {
                 checkTypeForDuplicateIndexSignatures(node);
-                registerForUnusedIdentifiersCheck(node);
+                checkUnusedTypeParameters(node);
             }
         }
         function checkTypeAliasDeclaration(node) {
@@ -29925,7 +29896,7 @@ var ts;
                 writeLine();
                 var sourceMappingURL = sourceMap.getSourceMappingURL();
                 if (sourceMappingURL) {
-                    write("//# " + "sourceMappingURL" + "=" + sourceMappingURL);
+                    write("//# sourceMappingURL=" + sourceMappingURL);
                 }
                 writeEmittedFiles(writer.getText(), jsFilePath, sourceMapFilePath, compilerOptions.emitBOM, sourceFiles);
                 sourceMap.reset();
@@ -33575,13 +33546,13 @@ var ts;
                         if (isES6ExportedDeclaration(node) && !(node.flags & 512) && decoratedClassAlias === undefined) {
                             write("export ");
                         }
+                        if (!isHoistedDeclarationInSystemModule) {
+                            write("let ");
+                        }
                         if (decoratedClassAlias !== undefined) {
-                            write("let " + decoratedClassAlias);
+                            write("" + decoratedClassAlias);
                         }
                         else {
-                            if (!isHoistedDeclarationInSystemModule) {
-                                write("let ");
-                            }
                             emitDeclarationName(node);
                         }
                         write(" = ");
@@ -35825,7 +35796,7 @@ var ts;
     ts.emitTime = 0;
     ts.ioReadTime = 0;
     ts.ioWriteTime = 0;
-    ts.version = "2.1.0";
+    ts.version = "2.0.0";
     var emptyArray = [];
     var defaultTypeRoots = ["node_modules/@types"];
     function findConfigFile(searchPath, fileExists) {
@@ -35905,7 +35876,12 @@ var ts;
         return { resolvedModule: resolvedFileName ? { resolvedFileName: resolvedFileName, isExternalLibraryImport: isExternalLibraryImport } : undefined, failedLookupLocations: failedLookupLocations };
     }
     function moduleHasNonRelativeName(moduleName) {
-        return !(ts.isRootedDiskPath(moduleName) || ts.isExternalModuleNameRelative(moduleName));
+        if (ts.isRootedDiskPath(moduleName)) {
+            return false;
+        }
+        var i = moduleName.lastIndexOf("./", 1);
+        var startsWithDotSlashOrDotDotSlash = i === 0 || (i === 1 && moduleName.charCodeAt(0) === 46);
+        return !startsWithDotSlashOrDotDotSlash;
     }
     function tryReadTypesSection(packageJsonPath, baseDirectory, state) {
         var jsonContent;
@@ -36561,22 +36537,6 @@ var ts;
         return ts.sortAndDeduplicateDiagnostics(diagnostics);
     }
     ts.getPreEmitDiagnostics = getPreEmitDiagnostics;
-    function formatDiagnostics(diagnostics, host) {
-        var output = "";
-        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
-            var diagnostic = diagnostics_1[_i];
-            if (diagnostic.file) {
-                var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character;
-                var fileName = diagnostic.file.fileName;
-                var relativeFileName = ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); });
-                output += relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): ";
-            }
-            var category = ts.DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += category + " TS" + diagnostic.code + ": " + flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) + host.getNewLine();
-        }
-        return output;
-    }
-    ts.formatDiagnostics = formatDiagnostics;
     function flattenDiagnosticMessageText(messageText, newLine) {
         if (typeof messageText === "string") {
             return messageText;
@@ -36652,7 +36612,7 @@ var ts;
         var resolvedTypeReferenceDirectives = {};
         var fileProcessingDiagnostics = ts.createDiagnosticCollection();
         var maxNodeModulesJsDepth = typeof options.maxNodeModuleJsDepth === "number" ? options.maxNodeModuleJsDepth : 2;
-        var currentNodeModulesDepth = 0;
+        var currentNodeModulesJsDepth = 0;
         var modulesWithElidedImports = {};
         var sourceFilesFoundSearchingNodeModules = {};
         var start = new Date().getTime();
@@ -36876,7 +36836,8 @@ var ts;
             return noDiagnosticsTypeChecker || (noDiagnosticsTypeChecker = ts.createTypeChecker(program, false));
         }
         function emit(sourceFile, writeFileCallback, cancellationToken) {
-            return runWithCancellationToken(function () { return emitWorker(program, sourceFile, writeFileCallback, cancellationToken); });
+            var _this = this;
+            return runWithCancellationToken(function () { return emitWorker(_this, sourceFile, writeFileCallback, cancellationToken); });
         }
         function isEmitBlocked(emitFileName) {
             return hasEmitBlockingDiagnostics.contains(ts.toPath(emitFileName, currentDirectory, getCanonicalFileName));
@@ -37283,17 +37244,8 @@ var ts;
                 if (file_1 && options.forceConsistentCasingInFileNames && ts.getNormalizedAbsolutePath(file_1.fileName, currentDirectory) !== ts.getNormalizedAbsolutePath(fileName, currentDirectory)) {
                     reportFileNamesDifferOnlyInCasingError(fileName, file_1.fileName, refFile, refPos, refEnd);
                 }
-                if (file_1 && ts.lookUp(sourceFilesFoundSearchingNodeModules, file_1.path) && currentNodeModulesDepth == 0) {
-                    sourceFilesFoundSearchingNodeModules[file_1.path] = false;
-                    if (!options.noResolve) {
-                        processReferencedFiles(file_1, ts.getDirectoryPath(fileName), isDefaultLib);
-                        processTypeReferenceDirectives(file_1);
-                    }
-                    modulesWithElidedImports[file_1.path] = false;
-                    processImportedModules(file_1, ts.getDirectoryPath(fileName));
-                }
-                else if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
-                    if (currentNodeModulesDepth < maxNodeModulesJsDepth) {
+                if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
+                    if (currentNodeModulesJsDepth < maxNodeModulesJsDepth) {
                         modulesWithElidedImports[file_1.path] = false;
                         processImportedModules(file_1, ts.getDirectoryPath(fileName));
                     }
@@ -37310,7 +37262,6 @@ var ts;
             });
             filesByName.set(path, file);
             if (file) {
-                sourceFilesFoundSearchingNodeModules[path] = (currentNodeModulesDepth > 0);
                 file.path = path;
                 if (host.useCaseSensitiveFileNames()) {
                     var existingFile = filesByNameIgnoreCase.get(path);
@@ -37411,9 +37362,12 @@ var ts;
                     var isFromNodeModulesSearch = resolution && resolution.isExternalLibraryImport;
                     var isJsFileFromNodeModules = isFromNodeModulesSearch && ts.hasJavaScriptFileExtension(resolution.resolvedFileName);
                     if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth++;
+                        sourceFilesFoundSearchingNodeModules[resolvedPath] = true;
                     }
-                    var elideImport = isJsFileFromNodeModules && currentNodeModulesDepth > maxNodeModulesJsDepth;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth++;
+                    }
+                    var elideImport = isJsFileFromNodeModules && currentNodeModulesJsDepth > maxNodeModulesJsDepth;
                     var shouldAddFile = resolution && !options.noResolve && i < file.imports.length && !elideImport;
                     if (elideImport) {
                         modulesWithElidedImports[file.path] = true;
@@ -37421,8 +37375,8 @@ var ts;
                     else if (shouldAddFile) {
                         findSourceFile(resolution.resolvedFileName, resolvedPath, false, false, file, ts.skipTrivia(file.text, file.imports[i].pos), file.imports[i].end);
                     }
-                    if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth--;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth--;
                     }
                 }
             }
@@ -37741,12 +37695,12 @@ var ts;
         {
             name: "noUnusedLocals",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_locals
+            description: ts.Diagnostics.Report_Errors_on_Unused_Locals
         },
         {
             name: "noUnusedParameters",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_parameters
+            description: ts.Diagnostics.Report_Errors_on_Unused_Parameters
         },
         {
             name: "noLib",
@@ -38525,18 +38479,10 @@ var ts;
 })(ts || (ts = {}));
 var ts;
 (function (ts) {
-    var defaultFormatDiagnosticsHost = {
-        getCurrentDirectory: function () { return ts.sys.getCurrentDirectory(); },
-        getNewLine: function () { return ts.sys.newLine; },
-        getCanonicalFileName: ts.createGetCanonicalFileName(ts.sys.useCaseSensitiveFileNames)
-    };
-    var reportDiagnosticWorker = reportDiagnosticSimply;
-    function reportDiagnostic(diagnostic, host) {
-        reportDiagnosticWorker(diagnostic, host || defaultFormatDiagnosticsHost);
-    }
+    var reportDiagnostic = reportDiagnosticSimply;
     function reportDiagnostics(diagnostics, host) {
-        for (var _i = 0, diagnostics_2 = diagnostics; _i < diagnostics_2.length; _i++) {
-            var diagnostic = diagnostics_2[_i];
+        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
+            var diagnostic = diagnostics_1[_i];
             reportDiagnostic(diagnostic, host);
         }
     }
@@ -38607,8 +38553,19 @@ var ts;
         var diagnostic = ts.createCompilerDiagnostic.apply(undefined, arguments);
         return diagnostic.messageText;
     }
+    function getRelativeFileName(fileName, host) {
+        return host ? ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); }) : fileName;
+    }
     function reportDiagnosticSimply(diagnostic, host) {
-        ts.sys.write(ts.formatDiagnostics([diagnostic], host));
+        var output = "";
+        if (diagnostic.file) {
+            var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character;
+            var relativeFileName = getRelativeFileName(diagnostic.file.fileName, host);
+            output += relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): ";
+        }
+        var category = ts.DiagnosticCategory[diagnostic.category].toLowerCase();
+        output += category + " TS" + diagnostic.code + ": " + ts.flattenDiagnosticMessageText(diagnostic.messageText, ts.sys.newLine) + ts.sys.newLine;
+        ts.sys.write(output);
     }
     var redForegroundEscapeSequence = "\u001b[91m";
     var yellowForegroundEscapeSequence = "\u001b[93m";
@@ -38633,7 +38590,7 @@ var ts;
             var _a = ts.getLineAndCharacterOfPosition(file, start), firstLine = _a.line, firstLineChar = _a.character;
             var _b = ts.getLineAndCharacterOfPosition(file, start + length_3), lastLine = _b.line, lastLineChar = _b.character;
             var lastLineInFile = ts.getLineAndCharacterOfPosition(file, file.text.length).line;
-            var relativeFileName = host ? ts.convertToRelativePath(file.fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); }) : file.fileName;
+            var relativeFileName = getRelativeFileName(file.fileName, host);
             var hasMoreThanFiveLines = (lastLine - firstLine) >= 4;
             var gutterWidth = (lastLine + 1 + "").length;
             if (hasMoreThanFiveLines) {
@@ -38822,8 +38779,7 @@ var ts;
                 ts.sys.exit(ts.ExitStatus.DiagnosticsPresent_OutputsSkipped);
                 return;
             }
-            var cwd = ts.sys.getCurrentDirectory();
-            var configParseResult = ts.parseJsonConfigFileContent(configObject, ts.sys, ts.getNormalizedAbsolutePath(ts.getDirectoryPath(configFileName), cwd), commandLine.options, ts.getNormalizedAbsolutePath(configFileName, cwd));
+            var configParseResult = ts.parseJsonConfigFileContent(configObject, ts.sys, ts.getNormalizedAbsolutePath(ts.getDirectoryPath(configFileName), ts.sys.getCurrentDirectory()), commandLine.options, configFileName);
             if (configParseResult.errors.length > 0) {
                 reportDiagnostics(configParseResult.errors, undefined);
                 ts.sys.exit(ts.ExitStatus.DiagnosticsPresent_OutputsSkipped);
@@ -38860,7 +38816,7 @@ var ts;
                 compilerHost.fileExists = cachedFileExists;
             }
             if (compilerOptions.pretty) {
-                reportDiagnosticWorker = reportDiagnosticWithColorAndContext;
+                reportDiagnostic = reportDiagnosticWithColorAndContext;
             }
             cachedExistingFiles = {};
             var compileResult = compile(rootFileNames, compilerOptions, compilerHost);
@@ -39023,7 +38979,7 @@ var ts;
         output += ts.sys.newLine + ts.sys.newLine;
         var padding = makePadding(marginLength);
         output += getDiagnosticText(ts.Diagnostics.Examples_Colon_0, makePadding(marginLength - examplesLength) + "tsc hello.ts") + ts.sys.newLine;
-        output += padding + "tsc --outFile file.js file.ts" + ts.sys.newLine;
+        output += padding + "tsc --out file.js file.ts" + ts.sys.newLine;
         output += padding + "tsc @args.txt" + ts.sys.newLine;
         output += ts.sys.newLine;
         output += getDiagnosticText(ts.Diagnostics.Options_Colon) + ts.sys.newLine;

lib/tsserver.js

@@ -830,17 +830,10 @@ var ts;
         return true;
     }
     ts.containsPath = containsPath;
-    function startsWith(str, prefix) {
-        return str.lastIndexOf(prefix, 0) === 0;
-    }
-    ts.startsWith = startsWith;
-    function endsWith(str, suffix) {
-        var expectedPos = str.length - suffix.length;
-        return expectedPos >= 0 && str.indexOf(suffix, expectedPos) === expectedPos;
-    }
-    ts.endsWith = endsWith;
     function fileExtensionIs(path, extension) {
-        return path.length > extension.length && endsWith(path, extension);
+        var pathLen = path.length;
+        var extLen = extension.length;
+        return pathLen > extLen && path.substr(pathLen - extLen, extLen) === extension;
     }
     ts.fileExtensionIs = fileExtensionIs;
     function fileExtensionIsAny(path, extensions) {
@@ -1105,8 +1098,6 @@ var ts;
     }
     ts.objectAllocator = {
         getNodeConstructor: function () { return Node; },
-        getTokenConstructor: function () { return Node; },
-        getIdentifierConstructor: function () { return Node; },
         getSourceFileConstructor: function () { return Node; },
         getSymbolConstructor: function () { return Symbol; },
         getTypeConstructor: function () { return Type; },
@@ -1238,7 +1229,7 @@ var ts;
             function readDirectory(path, extensions, excludes, includes) {
                 return ts.matchFiles(path, extensions, excludes, includes, false, shell.CurrentDirectory, getAccessibleFileSystemEntries);
             }
-            var wscriptSystem = {
+            return {
                 args: args,
                 newLine: "\r\n",
                 useCaseSensitiveFileNames: false,
@@ -1257,7 +1248,7 @@ var ts;
                     return fso.FolderExists(path);
                 },
                 createDirectory: function (directoryName) {
-                    if (!wscriptSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         fso.CreateFolder(directoryName);
                     }
                 },
@@ -1277,7 +1268,6 @@ var ts;
                     }
                 }
             };
-            return wscriptSystem;
         }
         function getNodeSystem() {
             var _fs = require("fs");
@@ -1450,7 +1440,7 @@ var ts;
             function getDirectories(path) {
                 return ts.filter(_fs.readdirSync(path), function (p) { return fileSystemEntryExists(ts.combinePaths(path, p), 1); });
             }
-            var nodeSystem = {
+            return {
                 args: process.argv.slice(2),
                 newLine: _os.EOL,
                 useCaseSensitiveFileNames: useCaseSensitiveFileNames,
@@ -1500,7 +1490,7 @@ var ts;
                 fileExists: fileExists,
                 directoryExists: directoryExists,
                 createDirectory: function (directoryName) {
-                    if (!nodeSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         _fs.mkdirSync(directoryName);
                     }
                 },
@@ -1548,7 +1538,6 @@ var ts;
                     return _fs.realpathSync(path);
                 }
             };
-            return nodeSystem;
         }
         function getChakraSystem() {
             var realpath = ChakraHost.realpath && (function (path) { return ChakraHost.realpath(path); });
@@ -2298,8 +2287,8 @@ var ts;
         Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system: { code: 6131, category: ts.DiagnosticCategory.Error, key: "Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system_6131", message: "Cannot compile modules using option '{0}' unless the '--module' flag is 'amd' or 'system'." },
         File_name_0_has_a_1_extension_stripping_it: { code: 6132, category: ts.DiagnosticCategory.Message, key: "File_name_0_has_a_1_extension_stripping_it_6132", message: "File name '{0}' has a '{1}' extension - stripping it" },
         _0_is_declared_but_never_used: { code: 6133, category: ts.DiagnosticCategory.Error, key: "_0_is_declared_but_never_used_6133", message: "'{0}' is declared but never used." },
-        Report_errors_on_unused_locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_locals_6134", message: "Report errors on unused locals." },
-        Report_errors_on_unused_parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_parameters_6135", message: "Report errors on unused parameters." },
+        Report_Errors_on_Unused_Locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Locals_6134", message: "Report Errors on Unused Locals." },
+        Report_Errors_on_Unused_Parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Parameters_6135", message: "Report Errors on Unused Parameters." },
         The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files: { code: 6136, category: ts.DiagnosticCategory.Message, key: "The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files_6136", message: "The maximum dependency depth to search under node_modules and load JavaScript files" },
         No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0: { code: 6137, category: ts.DiagnosticCategory.Message, key: "No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0_6137", message: "No types specified in 'package.json' but 'allowJs' is set, so returning 'main' value of '{0}'" },
         Variable_0_implicitly_has_an_1_type: { code: 7005, category: ts.DiagnosticCategory.Error, key: "Variable_0_implicitly_has_an_1_type_7005", message: "Variable '{0}' implicitly has an '{1}' type." },
@@ -3977,12 +3966,12 @@ var ts;
         {
             name: "noUnusedLocals",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_locals
+            description: ts.Diagnostics.Report_Errors_on_Unused_Locals
         },
         {
             name: "noUnusedParameters",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_parameters
+            description: ts.Diagnostics.Report_Errors_on_Unused_Parameters
         },
         {
             name: "noLib",
@@ -5765,7 +5754,7 @@ var ts;
     }
     ts.isExpression = isExpression;
     function isExternalModuleNameRelative(moduleName) {
-        return /^\.\.?($|[\\/])/.test(moduleName);
+        return moduleName.substr(0, 2) === "./" || moduleName.substr(0, 3) === "../" || moduleName.substr(0, 2) === ".\\" || moduleName.substr(0, 3) === "..\\";
     }
     ts.isExternalModuleNameRelative = isExternalModuleNameRelative;
     function isInstantiatedModule(node, preserveConstEnums) {
@@ -7273,24 +7262,25 @@ var ts;
         return node.flags & 92 && node.parent.kind === 148 && ts.isClassLike(node.parent.parent);
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
+    function startsWith(str, prefix) {
+        return str.lastIndexOf(prefix, 0) === 0;
+    }
+    ts.startsWith = startsWith;
+    function endsWith(str, suffix) {
+        var expectedPos = str.length - suffix.length;
+        return str.indexOf(suffix, expectedPos) === expectedPos;
+    }
+    ts.endsWith = endsWith;
 })(ts || (ts = {}));
 var ts;
 (function (ts) {
     ts.parseTime = 0;
     var NodeConstructor;
-    var TokenConstructor;
-    var IdentifierConstructor;
     var SourceFileConstructor;
     function createNode(kind, pos, end) {
         if (kind === 256) {
             return new (SourceFileConstructor || (SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor()))(kind, pos, end);
         }
-        else if (kind === 69) {
-            return new (IdentifierConstructor || (IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor()))(kind, pos, end);
-        }
-        else if (kind < 139) {
-            return new (TokenConstructor || (TokenConstructor = ts.objectAllocator.getTokenConstructor()))(kind, pos, end);
-        }
         else {
             return new (NodeConstructor || (NodeConstructor = ts.objectAllocator.getNodeConstructor()))(kind, pos, end);
         }
@@ -7713,8 +7703,6 @@ var ts;
         var scanner = ts.createScanner(2, true);
         var disallowInAndDecoratorContext = 4194304 | 16777216;
         var NodeConstructor;
-        var TokenConstructor;
-        var IdentifierConstructor;
         var SourceFileConstructor;
         var sourceFile;
         var parseDiagnostics;
@@ -7740,8 +7728,6 @@ var ts;
         }
         function initializeState(fileName, _sourceText, languageVersion, _syntaxCursor, scriptKind) {
             NodeConstructor = ts.objectAllocator.getNodeConstructor();
-            TokenConstructor = ts.objectAllocator.getTokenConstructor();
-            IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor();
             SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor();
             sourceText = _sourceText;
             syntaxCursor = _syntaxCursor;
@@ -8048,9 +8034,7 @@ var ts;
             if (!(pos >= 0)) {
                 pos = scanner.getStartPos();
             }
-            return kind >= 139 ? new NodeConstructor(kind, pos, pos) :
-                kind === 69 ? new IdentifierConstructor(kind, pos, pos) :
-                    new TokenConstructor(kind, pos, pos);
+            return new NodeConstructor(kind, pos, pos);
         }
         function finishNode(node, end) {
             node.end = end === undefined ? scanner.getStartPos() : end;
@@ -11826,9 +11810,6 @@ var ts;
                                 case 55:
                                     if (canParseTag) {
                                         parentTagTerminated = !tryParseChildTag(jsDocTypeLiteral);
-                                        if (!parentTagTerminated) {
-                                            resumePos = scanner.getStartPos();
-                                        }
                                     }
                                     seenAsterisk = false;
                                     break;
@@ -16355,18 +16336,17 @@ var ts;
                 if (declaration.kind === 235) {
                     return links.type = checkExpression(declaration.expression);
                 }
-                if (declaration.flags & 134217728 && declaration.kind === 280 && declaration.typeExpression) {
-                    return links.type = getTypeFromTypeNode(declaration.typeExpression.type);
-                }
                 if (!pushTypeResolution(symbol, 0)) {
                     return unknownType;
                 }
                 var type = undefined;
-                if (declaration.kind === 187 ||
-                    declaration.kind === 172 && declaration.parent.kind === 187) {
-                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return decl.kind === 187 ?
-                        checkExpressionCached(decl.right) :
-                        checkExpressionCached(decl.parent.right); }));
+                if (declaration.kind === 187) {
+                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return checkExpressionCached(decl.right); }));
+                }
+                else if (declaration.kind === 172) {
+                    if (declaration.parent.kind === 187) {
+                        type = checkExpressionCached(declaration.parent.right);
+                    }
                 }
                 if (type === undefined) {
                     type = getWidenedTypeForVariableLikeDeclaration(declaration, true);
@@ -22873,7 +22853,7 @@ var ts;
         function getInferredClassType(symbol) {
             var links = getSymbolLinks(symbol);
             if (!links.inferredClassType) {
-                links.inferredClassType = createAnonymousType(symbol, symbol.members, emptyArray, emptyArray, undefined, undefined);
+                links.inferredClassType = createAnonymousType(undefined, symbol.members, emptyArray, emptyArray, undefined, undefined);
             }
             return links.inferredClassType;
         }
@@ -24093,7 +24073,7 @@ var ts;
                         checkAsyncFunctionReturnType(node);
                     }
                 }
-                if (noUnusedIdentifiers && !node.body) {
+                if (!node.body) {
                     checkUnusedTypeParameters(node);
                 }
             }
@@ -24989,7 +24969,6 @@ var ts;
                                 var parameter = local_1.valueDeclaration;
                                 if (compilerOptions.noUnusedParameters &&
                                     !ts.isParameterPropertyDeclaration(parameter) &&
-                                    !parameterIsThisKeyword(parameter) &&
                                     !parameterNameStartsWithUnderscore(parameter)) {
                                     error(local_1.valueDeclaration.name, ts.Diagnostics._0_is_declared_but_never_used, local_1.name);
                                 }
@@ -25005,9 +24984,6 @@ var ts;
                 }
             }
         }
-        function parameterIsThisKeyword(parameter) {
-            return parameter.name && parameter.name.originalKeywordKind === 97;
-        }
         function parameterNameStartsWithUnderscore(parameter) {
             return parameter.name && parameter.name.kind === 69 && parameter.name.text.charCodeAt(0) === 95;
         }
@@ -25036,14 +25012,9 @@ var ts;
         function checkUnusedTypeParameters(node) {
             if (compilerOptions.noUnusedLocals && !ts.isInAmbientContext(node)) {
                 if (node.typeParameters) {
-                    var symbol = getSymbolOfNode(node);
-                    var lastDeclaration = symbol && symbol.declarations && ts.lastOrUndefined(symbol.declarations);
-                    if (lastDeclaration !== node) {
-                        return;
-                    }
                     for (var _i = 0, _a = node.typeParameters; _i < _a.length; _i++) {
                         var typeParameter = _a[_i];
-                        if (!getMergedSymbol(typeParameter.symbol).isReferenced) {
+                        if (!typeParameter.symbol.isReferenced) {
                             error(typeParameter.name, ts.Diagnostics._0_is_declared_but_never_used, typeParameter.symbol.name);
                         }
                     }
@@ -26120,7 +26091,7 @@ var ts;
             ts.forEach(node.members, checkSourceElement);
             if (produceDiagnostics) {
                 checkTypeForDuplicateIndexSignatures(node);
-                registerForUnusedIdentifiersCheck(node);
+                checkUnusedTypeParameters(node);
             }
         }
         function checkTypeAliasDeclaration(node) {
@@ -30843,7 +30814,7 @@ var ts;
                 writeLine();
                 var sourceMappingURL = sourceMap.getSourceMappingURL();
                 if (sourceMappingURL) {
-                    write("//# " + "sourceMappingURL" + "=" + sourceMappingURL);
+                    write("//# sourceMappingURL=" + sourceMappingURL);
                 }
                 writeEmittedFiles(writer.getText(), jsFilePath, sourceMapFilePath, compilerOptions.emitBOM, sourceFiles);
                 sourceMap.reset();
@@ -34493,13 +34464,13 @@ var ts;
                         if (isES6ExportedDeclaration(node) && !(node.flags & 512) && decoratedClassAlias === undefined) {
                             write("export ");
                         }
+                        if (!isHoistedDeclarationInSystemModule) {
+                            write("let ");
+                        }
                         if (decoratedClassAlias !== undefined) {
-                            write("let " + decoratedClassAlias);
+                            write("" + decoratedClassAlias);
                         }
                         else {
-                            if (!isHoistedDeclarationInSystemModule) {
-                                write("let ");
-                            }
                             emitDeclarationName(node);
                         }
                         write(" = ");
@@ -36743,7 +36714,7 @@ var ts;
     ts.emitTime = 0;
     ts.ioReadTime = 0;
     ts.ioWriteTime = 0;
-    ts.version = "2.1.0";
+    ts.version = "2.0.0";
     var emptyArray = [];
     var defaultTypeRoots = ["node_modules/@types"];
     function findConfigFile(searchPath, fileExists) {
@@ -36823,7 +36794,12 @@ var ts;
         return { resolvedModule: resolvedFileName ? { resolvedFileName: resolvedFileName, isExternalLibraryImport: isExternalLibraryImport } : undefined, failedLookupLocations: failedLookupLocations };
     }
     function moduleHasNonRelativeName(moduleName) {
-        return !(ts.isRootedDiskPath(moduleName) || ts.isExternalModuleNameRelative(moduleName));
+        if (ts.isRootedDiskPath(moduleName)) {
+            return false;
+        }
+        var i = moduleName.lastIndexOf("./", 1);
+        var startsWithDotSlashOrDotDotSlash = i === 0 || (i === 1 && moduleName.charCodeAt(0) === 46);
+        return !startsWithDotSlashOrDotDotSlash;
     }
     function tryReadTypesSection(packageJsonPath, baseDirectory, state) {
         var jsonContent;
@@ -37479,22 +37455,6 @@ var ts;
         return ts.sortAndDeduplicateDiagnostics(diagnostics);
     }
     ts.getPreEmitDiagnostics = getPreEmitDiagnostics;
-    function formatDiagnostics(diagnostics, host) {
-        var output = "";
-        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
-            var diagnostic = diagnostics_1[_i];
-            if (diagnostic.file) {
-                var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character;
-                var fileName = diagnostic.file.fileName;
-                var relativeFileName = ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); });
-                output += relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): ";
-            }
-            var category = ts.DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += category + " TS" + diagnostic.code + ": " + flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) + host.getNewLine();
-        }
-        return output;
-    }
-    ts.formatDiagnostics = formatDiagnostics;
     function flattenDiagnosticMessageText(messageText, newLine) {
         if (typeof messageText === "string") {
             return messageText;
@@ -37570,7 +37530,7 @@ var ts;
         var resolvedTypeReferenceDirectives = {};
         var fileProcessingDiagnostics = ts.createDiagnosticCollection();
         var maxNodeModulesJsDepth = typeof options.maxNodeModuleJsDepth === "number" ? options.maxNodeModuleJsDepth : 2;
-        var currentNodeModulesDepth = 0;
+        var currentNodeModulesJsDepth = 0;
         var modulesWithElidedImports = {};
         var sourceFilesFoundSearchingNodeModules = {};
         var start = new Date().getTime();
@@ -37794,7 +37754,8 @@ var ts;
             return noDiagnosticsTypeChecker || (noDiagnosticsTypeChecker = ts.createTypeChecker(program, false));
         }
         function emit(sourceFile, writeFileCallback, cancellationToken) {
-            return runWithCancellationToken(function () { return emitWorker(program, sourceFile, writeFileCallback, cancellationToken); });
+            var _this = this;
+            return runWithCancellationToken(function () { return emitWorker(_this, sourceFile, writeFileCallback, cancellationToken); });
         }
         function isEmitBlocked(emitFileName) {
             return hasEmitBlockingDiagnostics.contains(ts.toPath(emitFileName, currentDirectory, getCanonicalFileName));
@@ -38201,17 +38162,8 @@ var ts;
                 if (file_1 && options.forceConsistentCasingInFileNames && ts.getNormalizedAbsolutePath(file_1.fileName, currentDirectory) !== ts.getNormalizedAbsolutePath(fileName, currentDirectory)) {
                     reportFileNamesDifferOnlyInCasingError(fileName, file_1.fileName, refFile, refPos, refEnd);
                 }
-                if (file_1 && ts.lookUp(sourceFilesFoundSearchingNodeModules, file_1.path) && currentNodeModulesDepth == 0) {
-                    sourceFilesFoundSearchingNodeModules[file_1.path] = false;
-                    if (!options.noResolve) {
-                        processReferencedFiles(file_1, ts.getDirectoryPath(fileName), isDefaultLib);
-                        processTypeReferenceDirectives(file_1);
-                    }
-                    modulesWithElidedImports[file_1.path] = false;
-                    processImportedModules(file_1, ts.getDirectoryPath(fileName));
-                }
-                else if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
-                    if (currentNodeModulesDepth < maxNodeModulesJsDepth) {
+                if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
+                    if (currentNodeModulesJsDepth < maxNodeModulesJsDepth) {
                         modulesWithElidedImports[file_1.path] = false;
                         processImportedModules(file_1, ts.getDirectoryPath(fileName));
                     }
@@ -38228,7 +38180,6 @@ var ts;
             });
             filesByName.set(path, file);
             if (file) {
-                sourceFilesFoundSearchingNodeModules[path] = (currentNodeModulesDepth > 0);
                 file.path = path;
                 if (host.useCaseSensitiveFileNames()) {
                     var existingFile = filesByNameIgnoreCase.get(path);
@@ -38329,9 +38280,12 @@ var ts;
                     var isFromNodeModulesSearch = resolution && resolution.isExternalLibraryImport;
                     var isJsFileFromNodeModules = isFromNodeModulesSearch && ts.hasJavaScriptFileExtension(resolution.resolvedFileName);
                     if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth++;
+                        sourceFilesFoundSearchingNodeModules[resolvedPath] = true;
                     }
-                    var elideImport = isJsFileFromNodeModules && currentNodeModulesDepth > maxNodeModulesJsDepth;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth++;
+                    }
+                    var elideImport = isJsFileFromNodeModules && currentNodeModulesJsDepth > maxNodeModulesJsDepth;
                     var shouldAddFile = resolution && !options.noResolve && i < file.imports.length && !elideImport;
                     if (elideImport) {
                         modulesWithElidedImports[file.path] = true;
@@ -38339,8 +38293,8 @@ var ts;
                     else if (shouldAddFile) {
                         findSourceFile(resolution.resolvedFileName, resolvedPath, false, false, file, ts.skipTrivia(file.text, file.imports[i].pos), file.imports[i].end);
                     }
-                    if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth--;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth--;
                     }
                 }
             }
@@ -39933,7 +39887,7 @@ var ts;
                     return createPatternMatch(PatternMatchKind.exact, punctuationStripped, candidate === chunk.text);
                 }
                 else {
-                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, ts.startsWith(candidate, chunk.text));
+                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, startsWith(candidate, chunk.text));
                 }
             }
             var isLowercase = chunk.isLowerCase;
@@ -40105,6 +40059,14 @@ var ts;
         var str = String.fromCharCode(ch);
         return str === str.toLowerCase();
     }
+    function startsWith(string, search) {
+        for (var i = 0, n = search.length; i < n; i++) {
+            if (string.charCodeAt(i) !== search.charCodeAt(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
     function indexOfIgnoringCase(string, value) {
         for (var i = 0, n = string.length - value.length; i <= n; i++) {
             if (startsWithIgnoringCase(string, value, i)) {
@@ -41589,9 +41551,6 @@ var ts;
                 }
                 return false;
             }
-            function shouldRescanJsxText(node) {
-                return node && node.kind === 244;
-            }
             function shouldRescanSlashToken(container) {
                 return container.kind === 10;
             }
@@ -41619,9 +41578,7 @@ var ts;
                             ? 3
                             : shouldRescanJsxIdentifier(n)
                                 ? 4
-                                : shouldRescanJsxText(n)
-                                    ? 5
-                                    : 0;
+                                : 0;
                 if (lastTokenInfo && expectedScanAction === lastScanAction) {
                     return fixTokenKind(lastTokenInfo, n);
                 }
@@ -41649,10 +41606,6 @@ var ts;
                     currentToken = scanner.scanJsxIdentifier();
                     lastScanAction = 4;
                 }
-                else if (expectedScanAction === 5) {
-                    currentToken = scanner.reScanJsxToken();
-                    lastScanAction = 5;
-                }
                 else {
                     lastScanAction = 0;
                 }
@@ -43901,20 +43854,19 @@ var ts;
         "version"
     ];
     var jsDocCompletionEntries;
-    function createNode(kind, pos, end, parent) {
-        var node = kind >= 139 ? new NodeObject(kind, pos, end) :
-            kind === 69 ? new IdentifierObject(kind, pos, end) :
-                new TokenObject(kind, pos, end);
+    function createNode(kind, pos, end, flags, parent) {
+        var node = new NodeObject(kind, pos, end);
+        node.flags = flags;
         node.parent = parent;
         return node;
     }
     var NodeObject = (function () {
         function NodeObject(kind, pos, end) {
+            this.kind = kind;
             this.pos = pos;
             this.end = end;
             this.flags = 0;
             this.parent = undefined;
-            this.kind = kind;
         }
         NodeObject.prototype.getSourceFile = function () {
             return ts.getSourceFileOfNode(this);
@@ -43949,14 +43901,14 @@ var ts;
                 var token = useJSDocScanner ? scanner.scanJSDocToken() : scanner.scan();
                 var textPos = scanner.getTextPos();
                 if (textPos <= end) {
-                    nodes.push(createNode(token, pos, textPos, this));
+                    nodes.push(createNode(token, pos, textPos, 0, this));
                 }
                 pos = textPos;
             }
             return pos;
         };
         NodeObject.prototype.createSyntaxList = function (nodes) {
-            var list = createNode(282, nodes.pos, nodes.end, this);
+            var list = createNode(282, nodes.pos, nodes.end, 0, this);
             list._children = [];
             var pos = nodes.pos;
             for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
@@ -44041,73 +43993,6 @@ var ts;
         };
         return NodeObject;
     }());
-    var TokenOrIdentifierObject = (function () {
-        function TokenOrIdentifierObject(pos, end) {
-            this.pos = pos;
-            this.end = end;
-            this.flags = 0;
-            this.parent = undefined;
-        }
-        TokenOrIdentifierObject.prototype.getSourceFile = function () {
-            return ts.getSourceFileOfNode(this);
-        };
-        TokenOrIdentifierObject.prototype.getStart = function (sourceFile, includeJsDocComment) {
-            return ts.getTokenPosOfNode(this, sourceFile, includeJsDocComment);
-        };
-        TokenOrIdentifierObject.prototype.getFullStart = function () {
-            return this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getEnd = function () {
-            return this.end;
-        };
-        TokenOrIdentifierObject.prototype.getWidth = function (sourceFile) {
-            return this.getEnd() - this.getStart(sourceFile);
-        };
-        TokenOrIdentifierObject.prototype.getFullWidth = function () {
-            return this.end - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getLeadingTriviaWidth = function (sourceFile) {
-            return this.getStart(sourceFile) - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getFullText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.pos, this.end);
-        };
-        TokenOrIdentifierObject.prototype.getText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.getStart(), this.getEnd());
-        };
-        TokenOrIdentifierObject.prototype.getChildCount = function (sourceFile) {
-            return 0;
-        };
-        TokenOrIdentifierObject.prototype.getChildAt = function (index, sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getChildren = function (sourceFile) {
-            return emptyArray;
-        };
-        TokenOrIdentifierObject.prototype.getFirstToken = function (sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getLastToken = function (sourceFile) {
-            return undefined;
-        };
-        return TokenOrIdentifierObject;
-    }());
-    var TokenObject = (function (_super) {
-        __extends(TokenObject, _super);
-        function TokenObject(kind, pos, end) {
-            _super.call(this, pos, end);
-            this.kind = kind;
-        }
-        return TokenObject;
-    }(TokenOrIdentifierObject));
-    var IdentifierObject = (function (_super) {
-        __extends(IdentifierObject, _super);
-        function IdentifierObject(kind, pos, end) {
-            _super.call(this, pos, end);
-        }
-        return IdentifierObject;
-    }(TokenOrIdentifierObject));
-    IdentifierObject.prototype.kind = 69;
     var SymbolObject = (function () {
         function SymbolObject(flags, name) {
             this.flags = flags;
@@ -49788,8 +49673,6 @@ var ts;
     function initializeServices() {
         ts.objectAllocator = {
             getNodeConstructor: function () { return NodeObject; },
-            getTokenConstructor: function () { return TokenObject; },
-            getIdentifierConstructor: function () { return IdentifierObject; },
             getSourceFileConstructor: function () { return SourceFileObject; },
             getSymbolConstructor: function () { return SymbolObject; },
             getTypeConstructor: function () { return TypeObject; },
@@ -50910,6 +50793,7 @@ var ts;
                 if (isOpen === void 0) { isOpen = false; }
                 this.host = host;
                 this.fileName = fileName;
+                this.content = content;
                 this.isOpen = isOpen;
                 this.children = [];
                 this.formatCodeOptions = ts.clone(CompilerService.getDefaultFormatCodeOptions(this.host));
@@ -52535,7 +52419,7 @@ var ts;
                     done: false,
                     leaf: function (relativeStart, relativeLength, ll) {
                         if (!f(ll, relativeStart, relativeLength)) {
-                            walkFns.done = true;
+                            this.done = true;
                         }
                     }
                 };
@@ -53185,7 +53069,7 @@ var ts;
         ioSession.listen();
     })(server = ts.server || (ts.server = {}));
 })(ts || (ts = {}));
-var debugObjectHost = new Function("return this")();
+var debugObjectHost = this;
 var ts;
 (function (ts) {
     function logInternalError(logger, err) {
@@ -53313,7 +53197,7 @@ var ts;
             return this.shimHost.getCurrentDirectory();
         };
         LanguageServiceShimHostAdapter.prototype.getDirectories = function (path) {
-            return JSON.parse(this.shimHost.getDirectories(path));
+            return this.shimHost.getDirectories(path);
         };
         LanguageServiceShimHostAdapter.prototype.getDefaultLibFileName = function (options) {
             return this.shimHost.getDefaultLibFileName(JSON.stringify(options));

lib/tsserverlibrary.d.ts

@@ -405,10 +405,7 @@ declare namespace ts {
     interface ModifiersArray extends NodeArray<Modifier> {
         flags: NodeFlags;
     }
-    interface Token extends Node {
-        __tokenTag: any;
-    }
-    interface Modifier extends Token {
+    interface Modifier extends Node {
     }
     interface Identifier extends PrimaryExpression {
         text: string;
@@ -2053,6 +2050,7 @@ declare namespace ts {
         getCancellationToken?(): CancellationToken;
         getDefaultLibFileName(options: CompilerOptions): string;
         getDefaultLibLocation?(): string;
+        getDefaultTypeDirectiveNames?(rootPath: string): string[];
         writeFile: WriteFileCallback;
         getCurrentDirectory(): string;
         getDirectories(path: string): string[];
@@ -2158,8 +2156,6 @@ declare namespace ts {
     function ensureTrailingDirectorySeparator(path: string): string;
     function comparePaths(a: string, b: string, currentDirectory: string, ignoreCase?: boolean): Comparison;
     function containsPath(parent: string, child: string, currentDirectory: string, ignoreCase?: boolean): boolean;
-    function startsWith(str: string, prefix: string): boolean;
-    function endsWith(str: string, suffix: string): boolean;
     function fileExtensionIs(path: string, extension: string): boolean;
     function fileExtensionIsAny(path: string, extensions: string[]): boolean;
     function getRegularExpressionForWildcard(specs: string[], basePath: string, usage: "files" | "directories" | "exclude"): string;
@@ -2197,8 +2193,6 @@ declare namespace ts {
     function changeExtension<T extends string | Path>(path: T, newExtension: string): T;
     interface ObjectAllocator {
         getNodeConstructor(): new (kind: SyntaxKind, pos?: number, end?: number) => Node;
-        getTokenConstructor(): new (kind: SyntaxKind, pos?: number, end?: number) => Token;
-        getIdentifierConstructor(): new (kind: SyntaxKind, pos?: number, end?: number) => Token;
         getSourceFileConstructor(): new (kind: SyntaxKind, pos?: number, end?: number) => SourceFile;
         getSymbolConstructor(): new (flags: SymbolFlags, name: string) => Symbol;
         getTypeConstructor(): new (checker: TypeChecker, flags: TypeFlags) => Type;
@@ -6462,13 +6456,13 @@ declare namespace ts {
             key: string;
             message: string;
         };
-        Report_errors_on_unused_locals: {
+        Report_Errors_on_Unused_Locals: {
             code: number;
             category: DiagnosticCategory;
             key: string;
             message: string;
         };
-        Report_errors_on_unused_parameters: {
+        Report_Errors_on_Unused_Parameters: {
             code: number;
             category: DiagnosticCategory;
             key: string;
@@ -7149,6 +7143,8 @@ declare namespace ts {
     function collapseTextChangeRangesAcrossMultipleVersions(changes: TextChangeRange[]): TextChangeRange;
     function getTypeParameterOwner(d: Declaration): Declaration;
     function isParameterPropertyDeclaration(node: ParameterDeclaration): boolean;
+    function startsWith(str: string, prefix: string): boolean;
+    function endsWith(str: string, suffix: string): boolean;
 }
 declare namespace ts {
     let parseTime: number;
@@ -7229,12 +7225,6 @@ declare namespace ts {
     const defaultInitCompilerOptions: CompilerOptions;
     function createCompilerHost(options: CompilerOptions, setParentNodes?: boolean): CompilerHost;
     function getPreEmitDiagnostics(program: Program, sourceFile?: SourceFile, cancellationToken?: CancellationToken): Diagnostic[];
-    interface FormatDiagnosticsHost {
-        getCurrentDirectory(): string;
-        getCanonicalFileName(fileName: string): string;
-        getNewLine(): string;
-    }
-    function formatDiagnostics(diagnostics: Diagnostic[], host: FormatDiagnosticsHost): string;
     function flattenDiagnosticMessageText(messageText: string | DiagnosticMessageChain, newLine: string): string;
     function getAutomaticTypeDirectiveNames(options: CompilerOptions, rootFiles: string[], host: CompilerHost): string[];
     function createProgram(rootNames: string[], options: CompilerOptions, host?: CompilerHost, oldProgram?: Program): Program;
@@ -8398,6 +8388,7 @@ declare namespace ts.server {
     class ScriptInfo {
         private host;
         fileName: string;
+        content: string;
         isOpen: boolean;
         svc: ScriptVersionCache;
         children: ScriptInfo[];
@@ -8738,7 +8729,7 @@ declare namespace ts {
         getLocalizedDiagnosticMessages(): string;
         getCancellationToken(): HostCancellationToken;
         getCurrentDirectory(): string;
-        getDirectories(path: string): string;
+        getDirectories(path: string): string[];
         getDefaultLibFileName(options: string): string;
         getNewLine?(): string;
         getProjectVersion?(): string;

lib/tsserverlibrary.js

@@ -830,17 +830,10 @@ var ts;
         return true;
     }
     ts.containsPath = containsPath;
-    function startsWith(str, prefix) {
-        return str.lastIndexOf(prefix, 0) === 0;
-    }
-    ts.startsWith = startsWith;
-    function endsWith(str, suffix) {
-        var expectedPos = str.length - suffix.length;
-        return expectedPos >= 0 && str.indexOf(suffix, expectedPos) === expectedPos;
-    }
-    ts.endsWith = endsWith;
     function fileExtensionIs(path, extension) {
-        return path.length > extension.length && endsWith(path, extension);
+        var pathLen = path.length;
+        var extLen = extension.length;
+        return pathLen > extLen && path.substr(pathLen - extLen, extLen) === extension;
     }
     ts.fileExtensionIs = fileExtensionIs;
     function fileExtensionIsAny(path, extensions) {
@@ -1105,8 +1098,6 @@ var ts;
     }
     ts.objectAllocator = {
         getNodeConstructor: function () { return Node; },
-        getTokenConstructor: function () { return Node; },
-        getIdentifierConstructor: function () { return Node; },
         getSourceFileConstructor: function () { return Node; },
         getSymbolConstructor: function () { return Symbol; },
         getTypeConstructor: function () { return Type; },
@@ -1238,7 +1229,7 @@ var ts;
             function readDirectory(path, extensions, excludes, includes) {
                 return ts.matchFiles(path, extensions, excludes, includes, false, shell.CurrentDirectory, getAccessibleFileSystemEntries);
             }
-            var wscriptSystem = {
+            return {
                 args: args,
                 newLine: "\r\n",
                 useCaseSensitiveFileNames: false,
@@ -1257,7 +1248,7 @@ var ts;
                     return fso.FolderExists(path);
                 },
                 createDirectory: function (directoryName) {
-                    if (!wscriptSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         fso.CreateFolder(directoryName);
                     }
                 },
@@ -1277,7 +1268,6 @@ var ts;
                     }
                 }
             };
-            return wscriptSystem;
         }
         function getNodeSystem() {
             var _fs = require("fs");
@@ -1450,7 +1440,7 @@ var ts;
             function getDirectories(path) {
                 return ts.filter(_fs.readdirSync(path), function (p) { return fileSystemEntryExists(ts.combinePaths(path, p), 1); });
             }
-            var nodeSystem = {
+            return {
                 args: process.argv.slice(2),
                 newLine: _os.EOL,
                 useCaseSensitiveFileNames: useCaseSensitiveFileNames,
@@ -1500,7 +1490,7 @@ var ts;
                 fileExists: fileExists,
                 directoryExists: directoryExists,
                 createDirectory: function (directoryName) {
-                    if (!nodeSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         _fs.mkdirSync(directoryName);
                     }
                 },
@@ -1548,7 +1538,6 @@ var ts;
                     return _fs.realpathSync(path);
                 }
             };
-            return nodeSystem;
         }
         function getChakraSystem() {
             var realpath = ChakraHost.realpath && (function (path) { return ChakraHost.realpath(path); });
@@ -2298,8 +2287,8 @@ var ts;
         Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system: { code: 6131, category: ts.DiagnosticCategory.Error, key: "Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system_6131", message: "Cannot compile modules using option '{0}' unless the '--module' flag is 'amd' or 'system'." },
         File_name_0_has_a_1_extension_stripping_it: { code: 6132, category: ts.DiagnosticCategory.Message, key: "File_name_0_has_a_1_extension_stripping_it_6132", message: "File name '{0}' has a '{1}' extension - stripping it" },
         _0_is_declared_but_never_used: { code: 6133, category: ts.DiagnosticCategory.Error, key: "_0_is_declared_but_never_used_6133", message: "'{0}' is declared but never used." },
-        Report_errors_on_unused_locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_locals_6134", message: "Report errors on unused locals." },
-        Report_errors_on_unused_parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_parameters_6135", message: "Report errors on unused parameters." },
+        Report_Errors_on_Unused_Locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Locals_6134", message: "Report Errors on Unused Locals." },
+        Report_Errors_on_Unused_Parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Parameters_6135", message: "Report Errors on Unused Parameters." },
         The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files: { code: 6136, category: ts.DiagnosticCategory.Message, key: "The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files_6136", message: "The maximum dependency depth to search under node_modules and load JavaScript files" },
         No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0: { code: 6137, category: ts.DiagnosticCategory.Message, key: "No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0_6137", message: "No types specified in 'package.json' but 'allowJs' is set, so returning 'main' value of '{0}'" },
         Variable_0_implicitly_has_an_1_type: { code: 7005, category: ts.DiagnosticCategory.Error, key: "Variable_0_implicitly_has_an_1_type_7005", message: "Variable '{0}' implicitly has an '{1}' type." },
@@ -3977,12 +3966,12 @@ var ts;
         {
             name: "noUnusedLocals",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_locals
+            description: ts.Diagnostics.Report_Errors_on_Unused_Locals
         },
         {
             name: "noUnusedParameters",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_parameters
+            description: ts.Diagnostics.Report_Errors_on_Unused_Parameters
         },
         {
             name: "noLib",
@@ -5765,7 +5754,7 @@ var ts;
     }
     ts.isExpression = isExpression;
     function isExternalModuleNameRelative(moduleName) {
-        return /^\.\.?($|[\\/])/.test(moduleName);
+        return moduleName.substr(0, 2) === "./" || moduleName.substr(0, 3) === "../" || moduleName.substr(0, 2) === ".\\" || moduleName.substr(0, 3) === "..\\";
     }
     ts.isExternalModuleNameRelative = isExternalModuleNameRelative;
     function isInstantiatedModule(node, preserveConstEnums) {
@@ -7273,24 +7262,25 @@ var ts;
         return node.flags & 92 && node.parent.kind === 148 && ts.isClassLike(node.parent.parent);
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
+    function startsWith(str, prefix) {
+        return str.lastIndexOf(prefix, 0) === 0;
+    }
+    ts.startsWith = startsWith;
+    function endsWith(str, suffix) {
+        var expectedPos = str.length - suffix.length;
+        return str.indexOf(suffix, expectedPos) === expectedPos;
+    }
+    ts.endsWith = endsWith;
 })(ts || (ts = {}));
 var ts;
 (function (ts) {
     ts.parseTime = 0;
     var NodeConstructor;
-    var TokenConstructor;
-    var IdentifierConstructor;
     var SourceFileConstructor;
     function createNode(kind, pos, end) {
         if (kind === 256) {
             return new (SourceFileConstructor || (SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor()))(kind, pos, end);
         }
-        else if (kind === 69) {
-            return new (IdentifierConstructor || (IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor()))(kind, pos, end);
-        }
-        else if (kind < 139) {
-            return new (TokenConstructor || (TokenConstructor = ts.objectAllocator.getTokenConstructor()))(kind, pos, end);
-        }
         else {
             return new (NodeConstructor || (NodeConstructor = ts.objectAllocator.getNodeConstructor()))(kind, pos, end);
         }
@@ -7713,8 +7703,6 @@ var ts;
         var scanner = ts.createScanner(2, true);
         var disallowInAndDecoratorContext = 4194304 | 16777216;
         var NodeConstructor;
-        var TokenConstructor;
-        var IdentifierConstructor;
         var SourceFileConstructor;
         var sourceFile;
         var parseDiagnostics;
@@ -7740,8 +7728,6 @@ var ts;
         }
         function initializeState(fileName, _sourceText, languageVersion, _syntaxCursor, scriptKind) {
             NodeConstructor = ts.objectAllocator.getNodeConstructor();
-            TokenConstructor = ts.objectAllocator.getTokenConstructor();
-            IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor();
             SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor();
             sourceText = _sourceText;
             syntaxCursor = _syntaxCursor;
@@ -8048,9 +8034,7 @@ var ts;
             if (!(pos >= 0)) {
                 pos = scanner.getStartPos();
             }
-            return kind >= 139 ? new NodeConstructor(kind, pos, pos) :
-                kind === 69 ? new IdentifierConstructor(kind, pos, pos) :
-                    new TokenConstructor(kind, pos, pos);
+            return new NodeConstructor(kind, pos, pos);
         }
         function finishNode(node, end) {
             node.end = end === undefined ? scanner.getStartPos() : end;
@@ -11826,9 +11810,6 @@ var ts;
                                 case 55:
                                     if (canParseTag) {
                                         parentTagTerminated = !tryParseChildTag(jsDocTypeLiteral);
-                                        if (!parentTagTerminated) {
-                                            resumePos = scanner.getStartPos();
-                                        }
                                     }
                                     seenAsterisk = false;
                                     break;
@@ -16355,18 +16336,17 @@ var ts;
                 if (declaration.kind === 235) {
                     return links.type = checkExpression(declaration.expression);
                 }
-                if (declaration.flags & 134217728 && declaration.kind === 280 && declaration.typeExpression) {
-                    return links.type = getTypeFromTypeNode(declaration.typeExpression.type);
-                }
                 if (!pushTypeResolution(symbol, 0)) {
                     return unknownType;
                 }
                 var type = undefined;
-                if (declaration.kind === 187 ||
-                    declaration.kind === 172 && declaration.parent.kind === 187) {
-                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return decl.kind === 187 ?
-                        checkExpressionCached(decl.right) :
-                        checkExpressionCached(decl.parent.right); }));
+                if (declaration.kind === 187) {
+                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return checkExpressionCached(decl.right); }));
+                }
+                else if (declaration.kind === 172) {
+                    if (declaration.parent.kind === 187) {
+                        type = checkExpressionCached(declaration.parent.right);
+                    }
                 }
                 if (type === undefined) {
                     type = getWidenedTypeForVariableLikeDeclaration(declaration, true);
@@ -22873,7 +22853,7 @@ var ts;
         function getInferredClassType(symbol) {
             var links = getSymbolLinks(symbol);
             if (!links.inferredClassType) {
-                links.inferredClassType = createAnonymousType(symbol, symbol.members, emptyArray, emptyArray, undefined, undefined);
+                links.inferredClassType = createAnonymousType(undefined, symbol.members, emptyArray, emptyArray, undefined, undefined);
             }
             return links.inferredClassType;
         }
@@ -24093,7 +24073,7 @@ var ts;
                         checkAsyncFunctionReturnType(node);
                     }
                 }
-                if (noUnusedIdentifiers && !node.body) {
+                if (!node.body) {
                     checkUnusedTypeParameters(node);
                 }
             }
@@ -24989,7 +24969,6 @@ var ts;
                                 var parameter = local_1.valueDeclaration;
                                 if (compilerOptions.noUnusedParameters &&
                                     !ts.isParameterPropertyDeclaration(parameter) &&
-                                    !parameterIsThisKeyword(parameter) &&
                                     !parameterNameStartsWithUnderscore(parameter)) {
                                     error(local_1.valueDeclaration.name, ts.Diagnostics._0_is_declared_but_never_used, local_1.name);
                                 }
@@ -25005,9 +24984,6 @@ var ts;
                 }
             }
         }
-        function parameterIsThisKeyword(parameter) {
-            return parameter.name && parameter.name.originalKeywordKind === 97;
-        }
         function parameterNameStartsWithUnderscore(parameter) {
             return parameter.name && parameter.name.kind === 69 && parameter.name.text.charCodeAt(0) === 95;
         }
@@ -25036,14 +25012,9 @@ var ts;
         function checkUnusedTypeParameters(node) {
             if (compilerOptions.noUnusedLocals && !ts.isInAmbientContext(node)) {
                 if (node.typeParameters) {
-                    var symbol = getSymbolOfNode(node);
-                    var lastDeclaration = symbol && symbol.declarations && ts.lastOrUndefined(symbol.declarations);
-                    if (lastDeclaration !== node) {
-                        return;
-                    }
                     for (var _i = 0, _a = node.typeParameters; _i < _a.length; _i++) {
                         var typeParameter = _a[_i];
-                        if (!getMergedSymbol(typeParameter.symbol).isReferenced) {
+                        if (!typeParameter.symbol.isReferenced) {
                             error(typeParameter.name, ts.Diagnostics._0_is_declared_but_never_used, typeParameter.symbol.name);
                         }
                     }
@@ -26120,7 +26091,7 @@ var ts;
             ts.forEach(node.members, checkSourceElement);
             if (produceDiagnostics) {
                 checkTypeForDuplicateIndexSignatures(node);
-                registerForUnusedIdentifiersCheck(node);
+                checkUnusedTypeParameters(node);
             }
         }
         function checkTypeAliasDeclaration(node) {
@@ -30843,7 +30814,7 @@ var ts;
                 writeLine();
                 var sourceMappingURL = sourceMap.getSourceMappingURL();
                 if (sourceMappingURL) {
-                    write("//# " + "sourceMappingURL" + "=" + sourceMappingURL);
+                    write("//# sourceMappingURL=" + sourceMappingURL);
                 }
                 writeEmittedFiles(writer.getText(), jsFilePath, sourceMapFilePath, compilerOptions.emitBOM, sourceFiles);
                 sourceMap.reset();
@@ -34493,13 +34464,13 @@ var ts;
                         if (isES6ExportedDeclaration(node) && !(node.flags & 512) && decoratedClassAlias === undefined) {
                             write("export ");
                         }
+                        if (!isHoistedDeclarationInSystemModule) {
+                            write("let ");
+                        }
                         if (decoratedClassAlias !== undefined) {
-                            write("let " + decoratedClassAlias);
+                            write("" + decoratedClassAlias);
                         }
                         else {
-                            if (!isHoistedDeclarationInSystemModule) {
-                                write("let ");
-                            }
                             emitDeclarationName(node);
                         }
                         write(" = ");
@@ -36743,7 +36714,7 @@ var ts;
     ts.emitTime = 0;
     ts.ioReadTime = 0;
     ts.ioWriteTime = 0;
-    ts.version = "2.1.0";
+    ts.version = "2.0.0";
     var emptyArray = [];
     var defaultTypeRoots = ["node_modules/@types"];
     function findConfigFile(searchPath, fileExists) {
@@ -36823,7 +36794,12 @@ var ts;
         return { resolvedModule: resolvedFileName ? { resolvedFileName: resolvedFileName, isExternalLibraryImport: isExternalLibraryImport } : undefined, failedLookupLocations: failedLookupLocations };
     }
     function moduleHasNonRelativeName(moduleName) {
-        return !(ts.isRootedDiskPath(moduleName) || ts.isExternalModuleNameRelative(moduleName));
+        if (ts.isRootedDiskPath(moduleName)) {
+            return false;
+        }
+        var i = moduleName.lastIndexOf("./", 1);
+        var startsWithDotSlashOrDotDotSlash = i === 0 || (i === 1 && moduleName.charCodeAt(0) === 46);
+        return !startsWithDotSlashOrDotDotSlash;
     }
     function tryReadTypesSection(packageJsonPath, baseDirectory, state) {
         var jsonContent;
@@ -37479,22 +37455,6 @@ var ts;
         return ts.sortAndDeduplicateDiagnostics(diagnostics);
     }
     ts.getPreEmitDiagnostics = getPreEmitDiagnostics;
-    function formatDiagnostics(diagnostics, host) {
-        var output = "";
-        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
-            var diagnostic = diagnostics_1[_i];
-            if (diagnostic.file) {
-                var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character;
-                var fileName = diagnostic.file.fileName;
-                var relativeFileName = ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); });
-                output += relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): ";
-            }
-            var category = ts.DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += category + " TS" + diagnostic.code + ": " + flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) + host.getNewLine();
-        }
-        return output;
-    }
-    ts.formatDiagnostics = formatDiagnostics;
     function flattenDiagnosticMessageText(messageText, newLine) {
         if (typeof messageText === "string") {
             return messageText;
@@ -37570,7 +37530,7 @@ var ts;
         var resolvedTypeReferenceDirectives = {};
         var fileProcessingDiagnostics = ts.createDiagnosticCollection();
         var maxNodeModulesJsDepth = typeof options.maxNodeModuleJsDepth === "number" ? options.maxNodeModuleJsDepth : 2;
-        var currentNodeModulesDepth = 0;
+        var currentNodeModulesJsDepth = 0;
         var modulesWithElidedImports = {};
         var sourceFilesFoundSearchingNodeModules = {};
         var start = new Date().getTime();
@@ -37794,7 +37754,8 @@ var ts;
             return noDiagnosticsTypeChecker || (noDiagnosticsTypeChecker = ts.createTypeChecker(program, false));
         }
         function emit(sourceFile, writeFileCallback, cancellationToken) {
-            return runWithCancellationToken(function () { return emitWorker(program, sourceFile, writeFileCallback, cancellationToken); });
+            var _this = this;
+            return runWithCancellationToken(function () { return emitWorker(_this, sourceFile, writeFileCallback, cancellationToken); });
         }
         function isEmitBlocked(emitFileName) {
             return hasEmitBlockingDiagnostics.contains(ts.toPath(emitFileName, currentDirectory, getCanonicalFileName));
@@ -38201,17 +38162,8 @@ var ts;
                 if (file_1 && options.forceConsistentCasingInFileNames && ts.getNormalizedAbsolutePath(file_1.fileName, currentDirectory) !== ts.getNormalizedAbsolutePath(fileName, currentDirectory)) {
                     reportFileNamesDifferOnlyInCasingError(fileName, file_1.fileName, refFile, refPos, refEnd);
                 }
-                if (file_1 && ts.lookUp(sourceFilesFoundSearchingNodeModules, file_1.path) && currentNodeModulesDepth == 0) {
-                    sourceFilesFoundSearchingNodeModules[file_1.path] = false;
-                    if (!options.noResolve) {
-                        processReferencedFiles(file_1, ts.getDirectoryPath(fileName), isDefaultLib);
-                        processTypeReferenceDirectives(file_1);
-                    }
-                    modulesWithElidedImports[file_1.path] = false;
-                    processImportedModules(file_1, ts.getDirectoryPath(fileName));
-                }
-                else if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
-                    if (currentNodeModulesDepth < maxNodeModulesJsDepth) {
+                if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
+                    if (currentNodeModulesJsDepth < maxNodeModulesJsDepth) {
                         modulesWithElidedImports[file_1.path] = false;
                         processImportedModules(file_1, ts.getDirectoryPath(fileName));
                     }
@@ -38228,7 +38180,6 @@ var ts;
             });
             filesByName.set(path, file);
             if (file) {
-                sourceFilesFoundSearchingNodeModules[path] = (currentNodeModulesDepth > 0);
                 file.path = path;
                 if (host.useCaseSensitiveFileNames()) {
                     var existingFile = filesByNameIgnoreCase.get(path);
@@ -38329,9 +38280,12 @@ var ts;
                     var isFromNodeModulesSearch = resolution && resolution.isExternalLibraryImport;
                     var isJsFileFromNodeModules = isFromNodeModulesSearch && ts.hasJavaScriptFileExtension(resolution.resolvedFileName);
                     if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth++;
+                        sourceFilesFoundSearchingNodeModules[resolvedPath] = true;
                     }
-                    var elideImport = isJsFileFromNodeModules && currentNodeModulesDepth > maxNodeModulesJsDepth;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth++;
+                    }
+                    var elideImport = isJsFileFromNodeModules && currentNodeModulesJsDepth > maxNodeModulesJsDepth;
                     var shouldAddFile = resolution && !options.noResolve && i < file.imports.length && !elideImport;
                     if (elideImport) {
                         modulesWithElidedImports[file.path] = true;
@@ -38339,8 +38293,8 @@ var ts;
                     else if (shouldAddFile) {
                         findSourceFile(resolution.resolvedFileName, resolvedPath, false, false, file, ts.skipTrivia(file.text, file.imports[i].pos), file.imports[i].end);
                     }
-                    if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth--;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth--;
                     }
                 }
             }
@@ -39933,7 +39887,7 @@ var ts;
                     return createPatternMatch(PatternMatchKind.exact, punctuationStripped, candidate === chunk.text);
                 }
                 else {
-                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, ts.startsWith(candidate, chunk.text));
+                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, startsWith(candidate, chunk.text));
                 }
             }
             var isLowercase = chunk.isLowerCase;
@@ -40105,6 +40059,14 @@ var ts;
         var str = String.fromCharCode(ch);
         return str === str.toLowerCase();
     }
+    function startsWith(string, search) {
+        for (var i = 0, n = search.length; i < n; i++) {
+            if (string.charCodeAt(i) !== search.charCodeAt(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
     function indexOfIgnoringCase(string, value) {
         for (var i = 0, n = string.length - value.length; i <= n; i++) {
             if (startsWithIgnoringCase(string, value, i)) {
@@ -41589,9 +41551,6 @@ var ts;
                 }
                 return false;
             }
-            function shouldRescanJsxText(node) {
-                return node && node.kind === 244;
-            }
             function shouldRescanSlashToken(container) {
                 return container.kind === 10;
             }
@@ -41619,9 +41578,7 @@ var ts;
                             ? 3
                             : shouldRescanJsxIdentifier(n)
                                 ? 4
-                                : shouldRescanJsxText(n)
-                                    ? 5
-                                    : 0;
+                                : 0;
                 if (lastTokenInfo && expectedScanAction === lastScanAction) {
                     return fixTokenKind(lastTokenInfo, n);
                 }
@@ -41649,10 +41606,6 @@ var ts;
                     currentToken = scanner.scanJsxIdentifier();
                     lastScanAction = 4;
                 }
-                else if (expectedScanAction === 5) {
-                    currentToken = scanner.reScanJsxToken();
-                    lastScanAction = 5;
-                }
                 else {
                     lastScanAction = 0;
                 }
@@ -43901,20 +43854,19 @@ var ts;
         "version"
     ];
     var jsDocCompletionEntries;
-    function createNode(kind, pos, end, parent) {
-        var node = kind >= 139 ? new NodeObject(kind, pos, end) :
-            kind === 69 ? new IdentifierObject(kind, pos, end) :
-                new TokenObject(kind, pos, end);
+    function createNode(kind, pos, end, flags, parent) {
+        var node = new NodeObject(kind, pos, end);
+        node.flags = flags;
         node.parent = parent;
         return node;
     }
     var NodeObject = (function () {
         function NodeObject(kind, pos, end) {
+            this.kind = kind;
             this.pos = pos;
             this.end = end;
             this.flags = 0;
             this.parent = undefined;
-            this.kind = kind;
         }
         NodeObject.prototype.getSourceFile = function () {
             return ts.getSourceFileOfNode(this);
@@ -43949,14 +43901,14 @@ var ts;
                 var token = useJSDocScanner ? scanner.scanJSDocToken() : scanner.scan();
                 var textPos = scanner.getTextPos();
                 if (textPos <= end) {
-                    nodes.push(createNode(token, pos, textPos, this));
+                    nodes.push(createNode(token, pos, textPos, 0, this));
                 }
                 pos = textPos;
             }
             return pos;
         };
         NodeObject.prototype.createSyntaxList = function (nodes) {
-            var list = createNode(282, nodes.pos, nodes.end, this);
+            var list = createNode(282, nodes.pos, nodes.end, 0, this);
             list._children = [];
             var pos = nodes.pos;
             for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
@@ -44041,73 +43993,6 @@ var ts;
         };
         return NodeObject;
     }());
-    var TokenOrIdentifierObject = (function () {
-        function TokenOrIdentifierObject(pos, end) {
-            this.pos = pos;
-            this.end = end;
-            this.flags = 0;
-            this.parent = undefined;
-        }
-        TokenOrIdentifierObject.prototype.getSourceFile = function () {
-            return ts.getSourceFileOfNode(this);
-        };
-        TokenOrIdentifierObject.prototype.getStart = function (sourceFile, includeJsDocComment) {
-            return ts.getTokenPosOfNode(this, sourceFile, includeJsDocComment);
-        };
-        TokenOrIdentifierObject.prototype.getFullStart = function () {
-            return this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getEnd = function () {
-            return this.end;
-        };
-        TokenOrIdentifierObject.prototype.getWidth = function (sourceFile) {
-            return this.getEnd() - this.getStart(sourceFile);
-        };
-        TokenOrIdentifierObject.prototype.getFullWidth = function () {
-            return this.end - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getLeadingTriviaWidth = function (sourceFile) {
-            return this.getStart(sourceFile) - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getFullText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.pos, this.end);
-        };
-        TokenOrIdentifierObject.prototype.getText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.getStart(), this.getEnd());
-        };
-        TokenOrIdentifierObject.prototype.getChildCount = function (sourceFile) {
-            return 0;
-        };
-        TokenOrIdentifierObject.prototype.getChildAt = function (index, sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getChildren = function (sourceFile) {
-            return emptyArray;
-        };
-        TokenOrIdentifierObject.prototype.getFirstToken = function (sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getLastToken = function (sourceFile) {
-            return undefined;
-        };
-        return TokenOrIdentifierObject;
-    }());
-    var TokenObject = (function (_super) {
-        __extends(TokenObject, _super);
-        function TokenObject(kind, pos, end) {
-            _super.call(this, pos, end);
-            this.kind = kind;
-        }
-        return TokenObject;
-    }(TokenOrIdentifierObject));
-    var IdentifierObject = (function (_super) {
-        __extends(IdentifierObject, _super);
-        function IdentifierObject(kind, pos, end) {
-            _super.call(this, pos, end);
-        }
-        return IdentifierObject;
-    }(TokenOrIdentifierObject));
-    IdentifierObject.prototype.kind = 69;
     var SymbolObject = (function () {
         function SymbolObject(flags, name) {
             this.flags = flags;
@@ -49788,8 +49673,6 @@ var ts;
     function initializeServices() {
         ts.objectAllocator = {
             getNodeConstructor: function () { return NodeObject; },
-            getTokenConstructor: function () { return TokenObject; },
-            getIdentifierConstructor: function () { return IdentifierObject; },
             getSourceFileConstructor: function () { return SourceFileObject; },
             getSymbolConstructor: function () { return SymbolObject; },
             getTypeConstructor: function () { return TypeObject; },
@@ -50910,6 +50793,7 @@ var ts;
                 if (isOpen === void 0) { isOpen = false; }
                 this.host = host;
                 this.fileName = fileName;
+                this.content = content;
                 this.isOpen = isOpen;
                 this.children = [];
                 this.formatCodeOptions = ts.clone(CompilerService.getDefaultFormatCodeOptions(this.host));
@@ -52535,7 +52419,7 @@ var ts;
                     done: false,
                     leaf: function (relativeStart, relativeLength, ll) {
                         if (!f(ll, relativeStart, relativeLength)) {
-                            walkFns.done = true;
+                            this.done = true;
                         }
                     }
                 };
@@ -52951,7 +52835,7 @@ var ts;
         server.LineLeaf = LineLeaf;
     })(server = ts.server || (ts.server = {}));
 })(ts || (ts = {}));
-var debugObjectHost = new Function("return this")();
+var debugObjectHost = this;
 var ts;
 (function (ts) {
     function logInternalError(logger, err) {
@@ -53079,7 +52963,7 @@ var ts;
             return this.shimHost.getCurrentDirectory();
         };
         LanguageServiceShimHostAdapter.prototype.getDirectories = function (path) {
-            return JSON.parse(this.shimHost.getDirectories(path));
+            return this.shimHost.getDirectories(path);
         };
         LanguageServiceShimHostAdapter.prototype.getDefaultLibFileName = function (options) {
             return this.shimHost.getDefaultLibFileName(JSON.stringify(options));

lib/typescript.d.ts

@@ -409,10 +409,7 @@ declare namespace ts {
     interface ModifiersArray extends NodeArray<Modifier> {
         flags: NodeFlags;
     }
-    interface Token extends Node {
-        __tokenTag: any;
-    }
-    interface Modifier extends Token {
+    interface Modifier extends Node {
     }
     interface Identifier extends PrimaryExpression {
         text: string;
@@ -1699,6 +1696,7 @@ declare namespace ts {
         getCancellationToken?(): CancellationToken;
         getDefaultLibFileName(options: CompilerOptions): string;
         getDefaultLibLocation?(): string;
+        getDefaultTypeDirectiveNames?(rootPath: string): string[];
         writeFile: WriteFileCallback;
         getCurrentDirectory(): string;
         getDirectories(path: string): string[];
@@ -1844,6 +1842,8 @@ declare namespace ts {
     function collapseTextChangeRangesAcrossMultipleVersions(changes: TextChangeRange[]): TextChangeRange;
     function getTypeParameterOwner(d: Declaration): Declaration;
     function isParameterPropertyDeclaration(node: ParameterDeclaration): boolean;
+    function startsWith(str: string, prefix: string): boolean;
+    function endsWith(str: string, suffix: string): boolean;
 }
 declare namespace ts {
     function createNode(kind: SyntaxKind, pos?: number, end?: number): Node;
@@ -1868,12 +1868,6 @@ declare namespace ts {
     function classicNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost): ResolvedModuleWithFailedLookupLocations;
     function createCompilerHost(options: CompilerOptions, setParentNodes?: boolean): CompilerHost;
     function getPreEmitDiagnostics(program: Program, sourceFile?: SourceFile, cancellationToken?: CancellationToken): Diagnostic[];
-    interface FormatDiagnosticsHost {
-        getCurrentDirectory(): string;
-        getCanonicalFileName(fileName: string): string;
-        getNewLine(): string;
-    }
-    function formatDiagnostics(diagnostics: Diagnostic[], host: FormatDiagnosticsHost): string;
     function flattenDiagnosticMessageText(messageText: string | DiagnosticMessageChain, newLine: string): string;
     /**
       * Given a set of options and a set of root files, returns the set of type directive names

lib/typescript.js

@@ -1756,19 +1756,10 @@ var ts;
         return true;
     }
     ts.containsPath = containsPath;
-    /* @internal */
-    function startsWith(str, prefix) {
-        return str.lastIndexOf(prefix, 0) === 0;
-    }
-    ts.startsWith = startsWith;
-    /* @internal */
-    function endsWith(str, suffix) {
-        var expectedPos = str.length - suffix.length;
-        return expectedPos >= 0 && str.indexOf(suffix, expectedPos) === expectedPos;
-    }
-    ts.endsWith = endsWith;
     function fileExtensionIs(path, extension) {
-        return path.length > extension.length && endsWith(path, extension);
+        var pathLen = path.length;
+        var extLen = extension.length;
+        return pathLen > extLen && path.substr(pathLen - extLen, extLen) === extension;
     }
     ts.fileExtensionIs = fileExtensionIs;
     function fileExtensionIsAny(path, extensions) {
@@ -2079,8 +2070,6 @@ var ts;
     }
     ts.objectAllocator = {
         getNodeConstructor: function () { return Node; },
-        getTokenConstructor: function () { return Node; },
-        getIdentifierConstructor: function () { return Node; },
         getSourceFileConstructor: function () { return Node; },
         getSymbolConstructor: function () { return Symbol; },
         getTypeConstructor: function () { return Type; },
@@ -2227,7 +2216,7 @@ var ts;
             function readDirectory(path, extensions, excludes, includes) {
                 return ts.matchFiles(path, extensions, excludes, includes, /*useCaseSensitiveFileNames*/ false, shell.CurrentDirectory, getAccessibleFileSystemEntries);
             }
-            var wscriptSystem = {
+            return {
                 args: args,
                 newLine: "\r\n",
                 useCaseSensitiveFileNames: false,
@@ -2246,7 +2235,7 @@ var ts;
                     return fso.FolderExists(path);
                 },
                 createDirectory: function (directoryName) {
-                    if (!wscriptSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         fso.CreateFolder(directoryName);
                     }
                 },
@@ -2266,7 +2255,6 @@ var ts;
                     }
                 }
             };
-            return wscriptSystem;
         }
         function getNodeSystem() {
             var _fs = require("fs");
@@ -2456,7 +2444,7 @@ var ts;
             function getDirectories(path) {
                 return ts.filter(_fs.readdirSync(path), function (p) { return fileSystemEntryExists(ts.combinePaths(path, p), 1 /* Directory */); });
             }
-            var nodeSystem = {
+            return {
                 args: process.argv.slice(2),
                 newLine: _os.EOL,
                 useCaseSensitiveFileNames: useCaseSensitiveFileNames,
@@ -2512,7 +2500,7 @@ var ts;
                 fileExists: fileExists,
                 directoryExists: directoryExists,
                 createDirectory: function (directoryName) {
-                    if (!nodeSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         _fs.mkdirSync(directoryName);
                     }
                 },
@@ -2560,7 +2548,6 @@ var ts;
                     return _fs.realpathSync(path);
                 }
             };
-            return nodeSystem;
         }
         function getChakraSystem() {
             var realpath = ChakraHost.realpath && (function (path) { return ChakraHost.realpath(path); });
@@ -3317,8 +3304,8 @@ var ts;
         Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system: { code: 6131, category: ts.DiagnosticCategory.Error, key: "Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system_6131", message: "Cannot compile modules using option '{0}' unless the '--module' flag is 'amd' or 'system'." },
         File_name_0_has_a_1_extension_stripping_it: { code: 6132, category: ts.DiagnosticCategory.Message, key: "File_name_0_has_a_1_extension_stripping_it_6132", message: "File name '{0}' has a '{1}' extension - stripping it" },
         _0_is_declared_but_never_used: { code: 6133, category: ts.DiagnosticCategory.Error, key: "_0_is_declared_but_never_used_6133", message: "'{0}' is declared but never used." },
-        Report_errors_on_unused_locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_locals_6134", message: "Report errors on unused locals." },
-        Report_errors_on_unused_parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_parameters_6135", message: "Report errors on unused parameters." },
+        Report_Errors_on_Unused_Locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Locals_6134", message: "Report Errors on Unused Locals." },
+        Report_Errors_on_Unused_Parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Parameters_6135", message: "Report Errors on Unused Parameters." },
         The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files: { code: 6136, category: ts.DiagnosticCategory.Message, key: "The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files_6136", message: "The maximum dependency depth to search under node_modules and load JavaScript files" },
         No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0: { code: 6137, category: ts.DiagnosticCategory.Message, key: "No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0_6137", message: "No types specified in 'package.json' but 'allowJs' is set, so returning 'main' value of '{0}'" },
         Variable_0_implicitly_has_an_1_type: { code: 7005, category: ts.DiagnosticCategory.Error, key: "Variable_0_implicitly_has_an_1_type_7005", message: "Variable '{0}' implicitly has an '{1}' type." },
@@ -6166,7 +6153,7 @@ var ts;
     function isExternalModuleNameRelative(moduleName) {
         // TypeScript 1.0 spec (April 2014): 11.2.1
         // An external module name is "relative" if the first term is "." or "..".
-        return /^\.\.?($|[\\/])/.test(moduleName);
+        return moduleName.substr(0, 2) === "./" || moduleName.substr(0, 3) === "../" || moduleName.substr(0, 2) === ".\\" || moduleName.substr(0, 3) === "..\\";
     }
     ts.isExternalModuleNameRelative = isExternalModuleNameRelative;
     function isInstantiatedModule(node, preserveConstEnums) {
@@ -7929,6 +7916,15 @@ var ts;
         return node.flags & 92 /* ParameterPropertyModifier */ && node.parent.kind === 148 /* Constructor */ && ts.isClassLike(node.parent.parent);
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
+    function startsWith(str, prefix) {
+        return str.lastIndexOf(prefix, 0) === 0;
+    }
+    ts.startsWith = startsWith;
+    function endsWith(str, suffix) {
+        var expectedPos = str.length - suffix.length;
+        return str.indexOf(suffix, expectedPos) === expectedPos;
+    }
+    ts.endsWith = endsWith;
 })(ts || (ts = {}));
 /// <reference path="utilities.ts"/>
 /// <reference path="scanner.ts"/>
@@ -7936,19 +7932,11 @@ var ts;
 (function (ts) {
     /* @internal */ ts.parseTime = 0;
     var NodeConstructor;
-    var TokenConstructor;
-    var IdentifierConstructor;
     var SourceFileConstructor;
     function createNode(kind, pos, end) {
         if (kind === 256 /* SourceFile */) {
             return new (SourceFileConstructor || (SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor()))(kind, pos, end);
         }
-        else if (kind === 69 /* Identifier */) {
-            return new (IdentifierConstructor || (IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor()))(kind, pos, end);
-        }
-        else if (kind < 139 /* FirstNode */) {
-            return new (TokenConstructor || (TokenConstructor = ts.objectAllocator.getTokenConstructor()))(kind, pos, end);
-        }
         else {
             return new (NodeConstructor || (NodeConstructor = ts.objectAllocator.getNodeConstructor()))(kind, pos, end);
         }
@@ -8398,8 +8386,6 @@ var ts;
         var disallowInAndDecoratorContext = 4194304 /* DisallowInContext */ | 16777216 /* DecoratorContext */;
         // capture constructors in 'initializeState' to avoid null checks
         var NodeConstructor;
-        var TokenConstructor;
-        var IdentifierConstructor;
         var SourceFileConstructor;
         var sourceFile;
         var parseDiagnostics;
@@ -8499,8 +8485,6 @@ var ts;
         }
         function initializeState(fileName, _sourceText, languageVersion, _syntaxCursor, scriptKind) {
             NodeConstructor = ts.objectAllocator.getNodeConstructor();
-            TokenConstructor = ts.objectAllocator.getTokenConstructor();
-            IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor();
             SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor();
             sourceText = _sourceText;
             syntaxCursor = _syntaxCursor;
@@ -8871,9 +8855,7 @@ var ts;
             if (!(pos >= 0)) {
                 pos = scanner.getStartPos();
             }
-            return kind >= 139 /* FirstNode */ ? new NodeConstructor(kind, pos, pos) :
-                kind === 69 /* Identifier */ ? new IdentifierConstructor(kind, pos, pos) :
-                    new TokenConstructor(kind, pos, pos);
+            return new NodeConstructor(kind, pos, pos);
         }
         function finishNode(node, end) {
             node.end = end === undefined ? scanner.getStartPos() : end;
@@ -13542,9 +13524,6 @@ var ts;
                                 case 55 /* AtToken */:
                                     if (canParseTag) {
                                         parentTagTerminated = !tryParseChildTag(jsDocTypeLiteral);
-                                        if (!parentTagTerminated) {
-                                            resumePos = scanner.getStartPos();
-                                        }
                                     }
                                     seenAsterisk = false;
                                     break;
@@ -19012,24 +18991,22 @@ var ts;
                 if (declaration.kind === 235 /* ExportAssignment */) {
                     return links.type = checkExpression(declaration.expression);
                 }
-                if (declaration.flags & 134217728 /* JavaScriptFile */ && declaration.kind === 280 /* JSDocPropertyTag */ && declaration.typeExpression) {
-                    return links.type = getTypeFromTypeNode(declaration.typeExpression.type);
-                }
                 // Handle variable, parameter or property
                 if (!pushTypeResolution(symbol, 0 /* Type */)) {
                     return unknownType;
                 }
                 var type = undefined;
-                // Handle certain special assignment kinds, which happen to union across multiple declarations:
-                // * module.exports = expr
-                // * exports.p = expr
-                // * this.p = expr
-                // * className.prototype.method = expr
-                if (declaration.kind === 187 /* BinaryExpression */ ||
-                    declaration.kind === 172 /* PropertyAccessExpression */ && declaration.parent.kind === 187 /* BinaryExpression */) {
-                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return decl.kind === 187 /* BinaryExpression */ ?
-                        checkExpressionCached(decl.right) :
-                        checkExpressionCached(decl.parent.right); }));
+                // Handle module.exports = expr or this.p = expr
+                if (declaration.kind === 187 /* BinaryExpression */) {
+                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return checkExpressionCached(decl.right); }));
+                }
+                else if (declaration.kind === 172 /* PropertyAccessExpression */) {
+                    // Declarations only exist for property access expressions for certain
+                    // special assignment kinds
+                    if (declaration.parent.kind === 187 /* BinaryExpression */) {
+                        // Handle exports.p = expr  or className.prototype.method = expr
+                        type = checkExpressionCached(declaration.parent.right);
+                    }
                 }
                 if (type === undefined) {
                     type = getWidenedTypeForVariableLikeDeclaration(declaration, /*reportErrors*/ true);
@@ -26784,7 +26761,7 @@ var ts;
         function getInferredClassType(symbol) {
             var links = getSymbolLinks(symbol);
             if (!links.inferredClassType) {
-                links.inferredClassType = createAnonymousType(symbol, symbol.members, emptyArray, emptyArray, /*stringIndexType*/ undefined, /*numberIndexType*/ undefined);
+                links.inferredClassType = createAnonymousType(undefined, symbol.members, emptyArray, emptyArray, /*stringIndexType*/ undefined, /*numberIndexType*/ undefined);
             }
             return links.inferredClassType;
         }
@@ -28225,7 +28202,7 @@ var ts;
                         checkAsyncFunctionReturnType(node);
                     }
                 }
-                if (noUnusedIdentifiers && !node.body) {
+                if (!node.body) {
                     checkUnusedTypeParameters(node);
                 }
             }
@@ -29364,7 +29341,6 @@ var ts;
                                 var parameter = local_1.valueDeclaration;
                                 if (compilerOptions.noUnusedParameters &&
                                     !ts.isParameterPropertyDeclaration(parameter) &&
-                                    !parameterIsThisKeyword(parameter) &&
                                     !parameterNameStartsWithUnderscore(parameter)) {
                                     error(local_1.valueDeclaration.name, ts.Diagnostics._0_is_declared_but_never_used, local_1.name);
                                 }
@@ -29380,9 +29356,6 @@ var ts;
                 }
             }
         }
-        function parameterIsThisKeyword(parameter) {
-            return parameter.name && parameter.name.originalKeywordKind === 97 /* ThisKeyword */;
-        }
         function parameterNameStartsWithUnderscore(parameter) {
             return parameter.name && parameter.name.kind === 69 /* Identifier */ && parameter.name.text.charCodeAt(0) === 95 /* _ */;
         }
@@ -29411,16 +29384,9 @@ var ts;
         function checkUnusedTypeParameters(node) {
             if (compilerOptions.noUnusedLocals && !ts.isInAmbientContext(node)) {
                 if (node.typeParameters) {
-                    // Only report errors on the last declaration for the type parameter container;
-                    // this ensures that all uses have been accounted for.
-                    var symbol = getSymbolOfNode(node);
-                    var lastDeclaration = symbol && symbol.declarations && ts.lastOrUndefined(symbol.declarations);
-                    if (lastDeclaration !== node) {
-                        return;
-                    }
                     for (var _i = 0, _a = node.typeParameters; _i < _a.length; _i++) {
                         var typeParameter = _a[_i];
-                        if (!getMergedSymbol(typeParameter.symbol).isReferenced) {
+                        if (!typeParameter.symbol.isReferenced) {
                             error(typeParameter.name, ts.Diagnostics._0_is_declared_but_never_used, typeParameter.symbol.name);
                         }
                     }
@@ -30753,7 +30719,7 @@ var ts;
             ts.forEach(node.members, checkSourceElement);
             if (produceDiagnostics) {
                 checkTypeForDuplicateIndexSignatures(node);
-                registerForUnusedIdentifiersCheck(node);
+                checkUnusedTypeParameters(node);
             }
         }
         function checkTypeAliasDeclaration(node) {
@@ -36017,7 +35983,7 @@ var ts;
                 writeLine();
                 var sourceMappingURL = sourceMap.getSourceMappingURL();
                 if (sourceMappingURL) {
-                    write("//# " + "sourceMappingURL" + "=" + sourceMappingURL); // Sometimes tools can sometimes see this line as a source mapping url comment
+                    write("//# sourceMappingURL=" + sourceMappingURL);
                 }
                 writeEmittedFiles(writer.getText(), jsFilePath, sourceMapFilePath, /*writeByteOrderMark*/ compilerOptions.emitBOM, sourceFiles);
                 // reset the state
@@ -37914,7 +37880,7 @@ var ts;
              *   if we should also export the value after its it changed
              * - check if node is a source level declaration to emit it differently,
              *   i.e non-exported variable statement 'var x = 1' is hoisted so
-             *   when we emit variable statement 'var' should be dropped.
+             *   we we emit variable statement 'var' should be dropped.
              */
             function isSourceFileLevelDeclarationInSystemJsModule(node, isExported) {
                 if (!node || !isCurrentFileSystemExternalModule()) {
@@ -40381,13 +40347,13 @@ var ts;
                         if (isES6ExportedDeclaration(node) && !(node.flags & 512 /* Default */) && decoratedClassAlias === undefined) {
                             write("export ");
                         }
+                        if (!isHoistedDeclarationInSystemModule) {
+                            write("let ");
+                        }
                         if (decoratedClassAlias !== undefined) {
-                            write("let " + decoratedClassAlias);
+                            write("" + decoratedClassAlias);
                         }
                         else {
-                            if (!isHoistedDeclarationInSystemModule) {
-                                write("let ");
-                            }
                             emitDeclarationName(node);
                         }
                         write(" = ");
@@ -40406,9 +40372,7 @@ var ts;
                 //
                 // We'll emit:
                 //
-                //      let C_1 = class C{};
-                //      C_1.a = 1;
-                //      C_1.b = 2; // so forth and so on
+                //      (_temp = class C { ... }, _temp.a = 1, _temp.b = 2, _temp)
                 //
                 // This keeps the expression as an expression, while ensuring that the static parts
                 // of it have been initialized by the time it is used.
@@ -42972,7 +42936,7 @@ var ts;
     /* @internal */ ts.ioReadTime = 0;
     /* @internal */ ts.ioWriteTime = 0;
     /** The version of the TypeScript compiler release */
-    ts.version = "2.1.0";
+    ts.version = "2.0.0";
     var emptyArray = [];
     var defaultTypeRoots = ["node_modules/@types"];
     function findConfigFile(searchPath, fileExists) {
@@ -43061,7 +43025,12 @@ var ts;
         return { resolvedModule: resolvedFileName ? { resolvedFileName: resolvedFileName, isExternalLibraryImport: isExternalLibraryImport } : undefined, failedLookupLocations: failedLookupLocations };
     }
     function moduleHasNonRelativeName(moduleName) {
-        return !(ts.isRootedDiskPath(moduleName) || ts.isExternalModuleNameRelative(moduleName));
+        if (ts.isRootedDiskPath(moduleName)) {
+            return false;
+        }
+        var i = moduleName.lastIndexOf("./", 1);
+        var startsWithDotSlashOrDotDotSlash = i === 0 || (i === 1 && moduleName.charCodeAt(0) === 46 /* dot */);
+        return !startsWithDotSlashOrDotDotSlash;
     }
     function tryReadTypesSection(packageJsonPath, baseDirectory, state) {
         var jsonContent;
@@ -43828,22 +43797,6 @@ var ts;
         return ts.sortAndDeduplicateDiagnostics(diagnostics);
     }
     ts.getPreEmitDiagnostics = getPreEmitDiagnostics;
-    function formatDiagnostics(diagnostics, host) {
-        var output = "";
-        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
-            var diagnostic = diagnostics_1[_i];
-            if (diagnostic.file) {
-                var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character;
-                var fileName = diagnostic.file.fileName;
-                var relativeFileName = ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); });
-                output += relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): ";
-            }
-            var category = ts.DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += category + " TS" + diagnostic.code + ": " + flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) + host.getNewLine();
-        }
-        return output;
-    }
-    ts.formatDiagnostics = formatDiagnostics;
     function flattenDiagnosticMessageText(messageText, newLine) {
         if (typeof messageText === "string") {
             return messageText;
@@ -43936,11 +43889,11 @@ var ts;
         // As all these operations happen - and are nested - within the createProgram call, they close over the below variables.
         // The current resolution depth is tracked by incrementing/decrementing as the depth first search progresses.
         var maxNodeModulesJsDepth = typeof options.maxNodeModuleJsDepth === "number" ? options.maxNodeModuleJsDepth : 2;
-        var currentNodeModulesDepth = 0;
+        var currentNodeModulesJsDepth = 0;
         // If a module has some of its imports skipped due to being at the depth limit under node_modules, then track
         // this, as it may be imported at a shallower depth later, and then it will need its skipped imports processed.
         var modulesWithElidedImports = {};
-        // Track source files that are source files found by searching under node_modules, as these shouldn't be compiled.
+        // Track source files that are JavaScript files found by searching under node_modules, as these shouldn't be compiled.
         var sourceFilesFoundSearchingNodeModules = {};
         var start = new Date().getTime();
         host = host || createCompilerHost(options);
@@ -44197,7 +44150,8 @@ var ts;
             return noDiagnosticsTypeChecker || (noDiagnosticsTypeChecker = ts.createTypeChecker(program, /*produceDiagnostics:*/ false));
         }
         function emit(sourceFile, writeFileCallback, cancellationToken) {
-            return runWithCancellationToken(function () { return emitWorker(program, sourceFile, writeFileCallback, cancellationToken); });
+            var _this = this;
+            return runWithCancellationToken(function () { return emitWorker(_this, sourceFile, writeFileCallback, cancellationToken); });
         }
         function isEmitBlocked(emitFileName) {
             return hasEmitBlockingDiagnostics.contains(ts.toPath(emitFileName, currentDirectory, getCanonicalFileName));
@@ -44649,19 +44603,9 @@ var ts;
                 if (file_1 && options.forceConsistentCasingInFileNames && ts.getNormalizedAbsolutePath(file_1.fileName, currentDirectory) !== ts.getNormalizedAbsolutePath(fileName, currentDirectory)) {
                     reportFileNamesDifferOnlyInCasingError(fileName, file_1.fileName, refFile, refPos, refEnd);
                 }
-                // If the file was previously found via a node_modules search, but is now being processed as a root file,
-                // then everything it sucks in may also be marked incorrectly, and needs to be checked again.
-                if (file_1 && ts.lookUp(sourceFilesFoundSearchingNodeModules, file_1.path) && currentNodeModulesDepth == 0) {
-                    sourceFilesFoundSearchingNodeModules[file_1.path] = false;
-                    if (!options.noResolve) {
-                        processReferencedFiles(file_1, ts.getDirectoryPath(fileName), isDefaultLib);
-                        processTypeReferenceDirectives(file_1);
-                    }
-                    modulesWithElidedImports[file_1.path] = false;
-                    processImportedModules(file_1, ts.getDirectoryPath(fileName));
-                }
-                else if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
-                    if (currentNodeModulesDepth < maxNodeModulesJsDepth) {
+                // See if we need to reprocess the imports due to prior skipped imports
+                if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
+                    if (currentNodeModulesJsDepth < maxNodeModulesJsDepth) {
                         modulesWithElidedImports[file_1.path] = false;
                         processImportedModules(file_1, ts.getDirectoryPath(fileName));
                     }
@@ -44679,7 +44623,6 @@ var ts;
             });
             filesByName.set(path, file);
             if (file) {
-                sourceFilesFoundSearchingNodeModules[path] = (currentNodeModulesDepth > 0);
                 file.path = path;
                 if (host.useCaseSensitiveFileNames()) {
                     // for case-sensitive file systems check if we've already seen some file with similar filename ignoring case
@@ -44794,9 +44737,12 @@ var ts;
                     var isFromNodeModulesSearch = resolution && resolution.isExternalLibraryImport;
                     var isJsFileFromNodeModules = isFromNodeModulesSearch && ts.hasJavaScriptFileExtension(resolution.resolvedFileName);
                     if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth++;
+                        sourceFilesFoundSearchingNodeModules[resolvedPath] = true;
                     }
-                    var elideImport = isJsFileFromNodeModules && currentNodeModulesDepth > maxNodeModulesJsDepth;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth++;
+                    }
+                    var elideImport = isJsFileFromNodeModules && currentNodeModulesJsDepth > maxNodeModulesJsDepth;
                     var shouldAddFile = resolution && !options.noResolve && i < file.imports.length && !elideImport;
                     if (elideImport) {
                         modulesWithElidedImports[file.path] = true;
@@ -44805,8 +44751,8 @@ var ts;
                         findSourceFile(resolution.resolvedFileName, resolvedPath, 
                         /*isDefaultLib*/ false, /*isReference*/ false, file, ts.skipTrivia(file.text, file.imports[i].pos), file.imports[i].end);
                     }
-                    if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth--;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth--;
                     }
                 }
             }
@@ -45144,12 +45090,12 @@ var ts;
         {
             name: "noUnusedLocals",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_locals
+            description: ts.Diagnostics.Report_Errors_on_Unused_Locals
         },
         {
             name: "noUnusedParameters",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_parameters
+            description: ts.Diagnostics.Report_Errors_on_Unused_Parameters
         },
         {
             name: "noLib",
@@ -47141,7 +47087,7 @@ var ts;
                 else {
                     // b) Check if the part is a prefix of the candidate, in a case insensitive or sensitive
                     //    manner.  If it does, return that there was a prefix match.
-                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, /*isCaseSensitive:*/ ts.startsWith(candidate, chunk.text));
+                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, /*isCaseSensitive:*/ startsWith(candidate, chunk.text));
                 }
             }
             var isLowercase = chunk.isLowerCase;
@@ -47407,6 +47353,14 @@ var ts;
         var str = String.fromCharCode(ch);
         return str === str.toLowerCase();
     }
+    function startsWith(string, search) {
+        for (var i = 0, n = search.length; i < n; i++) {
+            if (string.charCodeAt(i) !== search.charCodeAt(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
     // Assumes 'value' is already lowercase.
     function indexOfIgnoringCase(string, value) {
         for (var i = 0, n = string.length - value.length; i <= n; i++) {
@@ -49251,7 +49205,6 @@ var ts;
             ScanAction[ScanAction["RescanSlashToken"] = 2] = "RescanSlashToken";
             ScanAction[ScanAction["RescanTemplateToken"] = 3] = "RescanTemplateToken";
             ScanAction[ScanAction["RescanJsxIdentifier"] = 4] = "RescanJsxIdentifier";
-            ScanAction[ScanAction["RescanJsxText"] = 5] = "RescanJsxText";
         })(ScanAction || (ScanAction = {}));
         function getFormattingScanner(sourceFile, startPos, endPos) {
             ts.Debug.assert(scanner === undefined);
@@ -49343,9 +49296,6 @@ var ts;
                 }
                 return false;
             }
-            function shouldRescanJsxText(node) {
-                return node && node.kind === 244 /* JsxText */;
-            }
             function shouldRescanSlashToken(container) {
                 return container.kind === 10 /* RegularExpressionLiteral */;
             }
@@ -49376,9 +49326,7 @@ var ts;
                             ? 3 /* RescanTemplateToken */
                             : shouldRescanJsxIdentifier(n)
                                 ? 4 /* RescanJsxIdentifier */
-                                : shouldRescanJsxText(n)
-                                    ? 5 /* RescanJsxText */
-                                    : 0 /* Scan */;
+                                : 0 /* Scan */;
                 if (lastTokenInfo && expectedScanAction === lastScanAction) {
                     // readTokenInfo was called before with the same expected scan action.
                     // No need to re-scan text, return existing 'lastTokenInfo'
@@ -49413,10 +49361,6 @@ var ts;
                     currentToken = scanner.scanJsxIdentifier();
                     lastScanAction = 4 /* RescanJsxIdentifier */;
                 }
-                else if (expectedScanAction === 5 /* RescanJsxText */) {
-                    currentToken = scanner.reScanJsxToken();
-                    lastScanAction = 5 /* RescanJsxText */;
-                }
                 else {
                     lastScanAction = 0 /* Scan */;
                 }
@@ -52089,20 +52033,19 @@ var ts;
         "version"
     ];
     var jsDocCompletionEntries;
-    function createNode(kind, pos, end, parent) {
-        var node = kind >= 139 /* FirstNode */ ? new NodeObject(kind, pos, end) :
-            kind === 69 /* Identifier */ ? new IdentifierObject(kind, pos, end) :
-                new TokenObject(kind, pos, end);
+    function createNode(kind, pos, end, flags, parent) {
+        var node = new NodeObject(kind, pos, end);
+        node.flags = flags;
         node.parent = parent;
         return node;
     }
     var NodeObject = (function () {
         function NodeObject(kind, pos, end) {
+            this.kind = kind;
             this.pos = pos;
             this.end = end;
             this.flags = 0 /* None */;
             this.parent = undefined;
-            this.kind = kind;
         }
         NodeObject.prototype.getSourceFile = function () {
             return ts.getSourceFileOfNode(this);
@@ -52137,14 +52080,14 @@ var ts;
                 var token = useJSDocScanner ? scanner.scanJSDocToken() : scanner.scan();
                 var textPos = scanner.getTextPos();
                 if (textPos <= end) {
-                    nodes.push(createNode(token, pos, textPos, this));
+                    nodes.push(createNode(token, pos, textPos, 0, this));
                 }
                 pos = textPos;
             }
             return pos;
         };
         NodeObject.prototype.createSyntaxList = function (nodes) {
-            var list = createNode(282 /* SyntaxList */, nodes.pos, nodes.end, this);
+            var list = createNode(282 /* SyntaxList */, nodes.pos, nodes.end, 0, this);
             list._children = [];
             var pos = nodes.pos;
             for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
@@ -52230,74 +52173,6 @@ var ts;
         };
         return NodeObject;
     }());
-    var TokenOrIdentifierObject = (function () {
-        function TokenOrIdentifierObject(pos, end) {
-            // Set properties in same order as NodeObject
-            this.pos = pos;
-            this.end = end;
-            this.flags = 0 /* None */;
-            this.parent = undefined;
-        }
-        TokenOrIdentifierObject.prototype.getSourceFile = function () {
-            return ts.getSourceFileOfNode(this);
-        };
-        TokenOrIdentifierObject.prototype.getStart = function (sourceFile, includeJsDocComment) {
-            return ts.getTokenPosOfNode(this, sourceFile, includeJsDocComment);
-        };
-        TokenOrIdentifierObject.prototype.getFullStart = function () {
-            return this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getEnd = function () {
-            return this.end;
-        };
-        TokenOrIdentifierObject.prototype.getWidth = function (sourceFile) {
-            return this.getEnd() - this.getStart(sourceFile);
-        };
-        TokenOrIdentifierObject.prototype.getFullWidth = function () {
-            return this.end - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getLeadingTriviaWidth = function (sourceFile) {
-            return this.getStart(sourceFile) - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getFullText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.pos, this.end);
-        };
-        TokenOrIdentifierObject.prototype.getText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.getStart(), this.getEnd());
-        };
-        TokenOrIdentifierObject.prototype.getChildCount = function (sourceFile) {
-            return 0;
-        };
-        TokenOrIdentifierObject.prototype.getChildAt = function (index, sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getChildren = function (sourceFile) {
-            return emptyArray;
-        };
-        TokenOrIdentifierObject.prototype.getFirstToken = function (sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getLastToken = function (sourceFile) {
-            return undefined;
-        };
-        return TokenOrIdentifierObject;
-    }());
-    var TokenObject = (function (_super) {
-        __extends(TokenObject, _super);
-        function TokenObject(kind, pos, end) {
-            _super.call(this, pos, end);
-            this.kind = kind;
-        }
-        return TokenObject;
-    }(TokenOrIdentifierObject));
-    var IdentifierObject = (function (_super) {
-        __extends(IdentifierObject, _super);
-        function IdentifierObject(kind, pos, end) {
-            _super.call(this, pos, end);
-        }
-        return IdentifierObject;
-    }(TokenOrIdentifierObject));
-    IdentifierObject.prototype.kind = 69 /* Identifier */;
     var SymbolObject = (function () {
         function SymbolObject(flags, name) {
             this.flags = flags;
@@ -59062,8 +58937,6 @@ var ts;
     function initializeServices() {
         ts.objectAllocator = {
             getNodeConstructor: function () { return NodeObject; },
-            getTokenConstructor: function () { return TokenObject; },
-            getIdentifierConstructor: function () { return IdentifierObject; },
             getSourceFileConstructor: function () { return SourceFileObject; },
             getSymbolConstructor: function () { return SymbolObject; },
             getTypeConstructor: function () { return TypeObject; },
@@ -59689,7 +59562,7 @@ var ts;
 //
 /// <reference path='services.ts' />
 /* @internal */
-var debugObjectHost = new Function("return this")();
+var debugObjectHost = this;
 // We need to use 'null' to interface with the managed side.
 /* tslint:disable:no-null-keyword */
 /* tslint:disable:no-in-operator */
@@ -59828,7 +59701,7 @@ var ts;
             return this.shimHost.getCurrentDirectory();
         };
         LanguageServiceShimHostAdapter.prototype.getDirectories = function (path) {
-            return JSON.parse(this.shimHost.getDirectories(path));
+            return this.shimHost.getDirectories(path);
         };
         LanguageServiceShimHostAdapter.prototype.getDefaultLibFileName = function (options) {
             return this.shimHost.getDefaultLibFileName(JSON.stringify(options));

lib/typescriptServices.d.ts

@@ -409,10 +409,7 @@ declare namespace ts {
     interface ModifiersArray extends NodeArray<Modifier> {
         flags: NodeFlags;
     }
-    interface Token extends Node {
-        __tokenTag: any;
-    }
-    interface Modifier extends Token {
+    interface Modifier extends Node {
     }
     interface Identifier extends PrimaryExpression {
         text: string;
@@ -1699,6 +1696,7 @@ declare namespace ts {
         getCancellationToken?(): CancellationToken;
         getDefaultLibFileName(options: CompilerOptions): string;
         getDefaultLibLocation?(): string;
+        getDefaultTypeDirectiveNames?(rootPath: string): string[];
         writeFile: WriteFileCallback;
         getCurrentDirectory(): string;
         getDirectories(path: string): string[];
@@ -1844,6 +1842,8 @@ declare namespace ts {
     function collapseTextChangeRangesAcrossMultipleVersions(changes: TextChangeRange[]): TextChangeRange;
     function getTypeParameterOwner(d: Declaration): Declaration;
     function isParameterPropertyDeclaration(node: ParameterDeclaration): boolean;
+    function startsWith(str: string, prefix: string): boolean;
+    function endsWith(str: string, suffix: string): boolean;
 }
 declare namespace ts {
     function createNode(kind: SyntaxKind, pos?: number, end?: number): Node;
@@ -1868,12 +1868,6 @@ declare namespace ts {
     function classicNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost): ResolvedModuleWithFailedLookupLocations;
     function createCompilerHost(options: CompilerOptions, setParentNodes?: boolean): CompilerHost;
     function getPreEmitDiagnostics(program: Program, sourceFile?: SourceFile, cancellationToken?: CancellationToken): Diagnostic[];
-    interface FormatDiagnosticsHost {
-        getCurrentDirectory(): string;
-        getCanonicalFileName(fileName: string): string;
-        getNewLine(): string;
-    }
-    function formatDiagnostics(diagnostics: Diagnostic[], host: FormatDiagnosticsHost): string;
     function flattenDiagnosticMessageText(messageText: string | DiagnosticMessageChain, newLine: string): string;
     /**
       * Given a set of options and a set of root files, returns the set of type directive names

lib/typescriptServices.js

@@ -1756,19 +1756,10 @@ var ts;
         return true;
     }
     ts.containsPath = containsPath;
-    /* @internal */
-    function startsWith(str, prefix) {
-        return str.lastIndexOf(prefix, 0) === 0;
-    }
-    ts.startsWith = startsWith;
-    /* @internal */
-    function endsWith(str, suffix) {
-        var expectedPos = str.length - suffix.length;
-        return expectedPos >= 0 && str.indexOf(suffix, expectedPos) === expectedPos;
-    }
-    ts.endsWith = endsWith;
     function fileExtensionIs(path, extension) {
-        return path.length > extension.length && endsWith(path, extension);
+        var pathLen = path.length;
+        var extLen = extension.length;
+        return pathLen > extLen && path.substr(pathLen - extLen, extLen) === extension;
     }
     ts.fileExtensionIs = fileExtensionIs;
     function fileExtensionIsAny(path, extensions) {
@@ -2079,8 +2070,6 @@ var ts;
     }
     ts.objectAllocator = {
         getNodeConstructor: function () { return Node; },
-        getTokenConstructor: function () { return Node; },
-        getIdentifierConstructor: function () { return Node; },
         getSourceFileConstructor: function () { return Node; },
         getSymbolConstructor: function () { return Symbol; },
         getTypeConstructor: function () { return Type; },
@@ -2227,7 +2216,7 @@ var ts;
             function readDirectory(path, extensions, excludes, includes) {
                 return ts.matchFiles(path, extensions, excludes, includes, /*useCaseSensitiveFileNames*/ false, shell.CurrentDirectory, getAccessibleFileSystemEntries);
             }
-            var wscriptSystem = {
+            return {
                 args: args,
                 newLine: "\r\n",
                 useCaseSensitiveFileNames: false,
@@ -2246,7 +2235,7 @@ var ts;
                     return fso.FolderExists(path);
                 },
                 createDirectory: function (directoryName) {
-                    if (!wscriptSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         fso.CreateFolder(directoryName);
                     }
                 },
@@ -2266,7 +2255,6 @@ var ts;
                     }
                 }
             };
-            return wscriptSystem;
         }
         function getNodeSystem() {
             var _fs = require("fs");
@@ -2456,7 +2444,7 @@ var ts;
             function getDirectories(path) {
                 return ts.filter(_fs.readdirSync(path), function (p) { return fileSystemEntryExists(ts.combinePaths(path, p), 1 /* Directory */); });
             }
-            var nodeSystem = {
+            return {
                 args: process.argv.slice(2),
                 newLine: _os.EOL,
                 useCaseSensitiveFileNames: useCaseSensitiveFileNames,
@@ -2512,7 +2500,7 @@ var ts;
                 fileExists: fileExists,
                 directoryExists: directoryExists,
                 createDirectory: function (directoryName) {
-                    if (!nodeSystem.directoryExists(directoryName)) {
+                    if (!this.directoryExists(directoryName)) {
                         _fs.mkdirSync(directoryName);
                     }
                 },
@@ -2560,7 +2548,6 @@ var ts;
                     return _fs.realpathSync(path);
                 }
             };
-            return nodeSystem;
         }
         function getChakraSystem() {
             var realpath = ChakraHost.realpath && (function (path) { return ChakraHost.realpath(path); });
@@ -3317,8 +3304,8 @@ var ts;
         Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system: { code: 6131, category: ts.DiagnosticCategory.Error, key: "Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system_6131", message: "Cannot compile modules using option '{0}' unless the '--module' flag is 'amd' or 'system'." },
         File_name_0_has_a_1_extension_stripping_it: { code: 6132, category: ts.DiagnosticCategory.Message, key: "File_name_0_has_a_1_extension_stripping_it_6132", message: "File name '{0}' has a '{1}' extension - stripping it" },
         _0_is_declared_but_never_used: { code: 6133, category: ts.DiagnosticCategory.Error, key: "_0_is_declared_but_never_used_6133", message: "'{0}' is declared but never used." },
-        Report_errors_on_unused_locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_locals_6134", message: "Report errors on unused locals." },
-        Report_errors_on_unused_parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_errors_on_unused_parameters_6135", message: "Report errors on unused parameters." },
+        Report_Errors_on_Unused_Locals: { code: 6134, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Locals_6134", message: "Report Errors on Unused Locals." },
+        Report_Errors_on_Unused_Parameters: { code: 6135, category: ts.DiagnosticCategory.Message, key: "Report_Errors_on_Unused_Parameters_6135", message: "Report Errors on Unused Parameters." },
         The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files: { code: 6136, category: ts.DiagnosticCategory.Message, key: "The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files_6136", message: "The maximum dependency depth to search under node_modules and load JavaScript files" },
         No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0: { code: 6137, category: ts.DiagnosticCategory.Message, key: "No_types_specified_in_package_json_but_allowJs_is_set_so_returning_main_value_of_0_6137", message: "No types specified in 'package.json' but 'allowJs' is set, so returning 'main' value of '{0}'" },
         Variable_0_implicitly_has_an_1_type: { code: 7005, category: ts.DiagnosticCategory.Error, key: "Variable_0_implicitly_has_an_1_type_7005", message: "Variable '{0}' implicitly has an '{1}' type." },
@@ -6166,7 +6153,7 @@ var ts;
     function isExternalModuleNameRelative(moduleName) {
         // TypeScript 1.0 spec (April 2014): 11.2.1
         // An external module name is "relative" if the first term is "." or "..".
-        return /^\.\.?($|[\\/])/.test(moduleName);
+        return moduleName.substr(0, 2) === "./" || moduleName.substr(0, 3) === "../" || moduleName.substr(0, 2) === ".\\" || moduleName.substr(0, 3) === "..\\";
     }
     ts.isExternalModuleNameRelative = isExternalModuleNameRelative;
     function isInstantiatedModule(node, preserveConstEnums) {
@@ -7929,6 +7916,15 @@ var ts;
         return node.flags & 92 /* ParameterPropertyModifier */ && node.parent.kind === 148 /* Constructor */ && ts.isClassLike(node.parent.parent);
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
+    function startsWith(str, prefix) {
+        return str.lastIndexOf(prefix, 0) === 0;
+    }
+    ts.startsWith = startsWith;
+    function endsWith(str, suffix) {
+        var expectedPos = str.length - suffix.length;
+        return str.indexOf(suffix, expectedPos) === expectedPos;
+    }
+    ts.endsWith = endsWith;
 })(ts || (ts = {}));
 /// <reference path="utilities.ts"/>
 /// <reference path="scanner.ts"/>
@@ -7936,19 +7932,11 @@ var ts;
 (function (ts) {
     /* @internal */ ts.parseTime = 0;
     var NodeConstructor;
-    var TokenConstructor;
-    var IdentifierConstructor;
     var SourceFileConstructor;
     function createNode(kind, pos, end) {
         if (kind === 256 /* SourceFile */) {
             return new (SourceFileConstructor || (SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor()))(kind, pos, end);
         }
-        else if (kind === 69 /* Identifier */) {
-            return new (IdentifierConstructor || (IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor()))(kind, pos, end);
-        }
-        else if (kind < 139 /* FirstNode */) {
-            return new (TokenConstructor || (TokenConstructor = ts.objectAllocator.getTokenConstructor()))(kind, pos, end);
-        }
         else {
             return new (NodeConstructor || (NodeConstructor = ts.objectAllocator.getNodeConstructor()))(kind, pos, end);
         }
@@ -8398,8 +8386,6 @@ var ts;
         var disallowInAndDecoratorContext = 4194304 /* DisallowInContext */ | 16777216 /* DecoratorContext */;
         // capture constructors in 'initializeState' to avoid null checks
         var NodeConstructor;
-        var TokenConstructor;
-        var IdentifierConstructor;
         var SourceFileConstructor;
         var sourceFile;
         var parseDiagnostics;
@@ -8499,8 +8485,6 @@ var ts;
         }
         function initializeState(fileName, _sourceText, languageVersion, _syntaxCursor, scriptKind) {
             NodeConstructor = ts.objectAllocator.getNodeConstructor();
-            TokenConstructor = ts.objectAllocator.getTokenConstructor();
-            IdentifierConstructor = ts.objectAllocator.getIdentifierConstructor();
             SourceFileConstructor = ts.objectAllocator.getSourceFileConstructor();
             sourceText = _sourceText;
             syntaxCursor = _syntaxCursor;
@@ -8871,9 +8855,7 @@ var ts;
             if (!(pos >= 0)) {
                 pos = scanner.getStartPos();
             }
-            return kind >= 139 /* FirstNode */ ? new NodeConstructor(kind, pos, pos) :
-                kind === 69 /* Identifier */ ? new IdentifierConstructor(kind, pos, pos) :
-                    new TokenConstructor(kind, pos, pos);
+            return new NodeConstructor(kind, pos, pos);
         }
         function finishNode(node, end) {
             node.end = end === undefined ? scanner.getStartPos() : end;
@@ -13542,9 +13524,6 @@ var ts;
                                 case 55 /* AtToken */:
                                     if (canParseTag) {
                                         parentTagTerminated = !tryParseChildTag(jsDocTypeLiteral);
-                                        if (!parentTagTerminated) {
-                                            resumePos = scanner.getStartPos();
-                                        }
                                     }
                                     seenAsterisk = false;
                                     break;
@@ -19012,24 +18991,22 @@ var ts;
                 if (declaration.kind === 235 /* ExportAssignment */) {
                     return links.type = checkExpression(declaration.expression);
                 }
-                if (declaration.flags & 134217728 /* JavaScriptFile */ && declaration.kind === 280 /* JSDocPropertyTag */ && declaration.typeExpression) {
-                    return links.type = getTypeFromTypeNode(declaration.typeExpression.type);
-                }
                 // Handle variable, parameter or property
                 if (!pushTypeResolution(symbol, 0 /* Type */)) {
                     return unknownType;
                 }
                 var type = undefined;
-                // Handle certain special assignment kinds, which happen to union across multiple declarations:
-                // * module.exports = expr
-                // * exports.p = expr
-                // * this.p = expr
-                // * className.prototype.method = expr
-                if (declaration.kind === 187 /* BinaryExpression */ ||
-                    declaration.kind === 172 /* PropertyAccessExpression */ && declaration.parent.kind === 187 /* BinaryExpression */) {
-                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return decl.kind === 187 /* BinaryExpression */ ?
-                        checkExpressionCached(decl.right) :
-                        checkExpressionCached(decl.parent.right); }));
+                // Handle module.exports = expr or this.p = expr
+                if (declaration.kind === 187 /* BinaryExpression */) {
+                    type = getUnionType(ts.map(symbol.declarations, function (decl) { return checkExpressionCached(decl.right); }));
+                }
+                else if (declaration.kind === 172 /* PropertyAccessExpression */) {
+                    // Declarations only exist for property access expressions for certain
+                    // special assignment kinds
+                    if (declaration.parent.kind === 187 /* BinaryExpression */) {
+                        // Handle exports.p = expr  or className.prototype.method = expr
+                        type = checkExpressionCached(declaration.parent.right);
+                    }
                 }
                 if (type === undefined) {
                     type = getWidenedTypeForVariableLikeDeclaration(declaration, /*reportErrors*/ true);
@@ -26784,7 +26761,7 @@ var ts;
         function getInferredClassType(symbol) {
             var links = getSymbolLinks(symbol);
             if (!links.inferredClassType) {
-                links.inferredClassType = createAnonymousType(symbol, symbol.members, emptyArray, emptyArray, /*stringIndexType*/ undefined, /*numberIndexType*/ undefined);
+                links.inferredClassType = createAnonymousType(undefined, symbol.members, emptyArray, emptyArray, /*stringIndexType*/ undefined, /*numberIndexType*/ undefined);
             }
             return links.inferredClassType;
         }
@@ -28225,7 +28202,7 @@ var ts;
                         checkAsyncFunctionReturnType(node);
                     }
                 }
-                if (noUnusedIdentifiers && !node.body) {
+                if (!node.body) {
                     checkUnusedTypeParameters(node);
                 }
             }
@@ -29364,7 +29341,6 @@ var ts;
                                 var parameter = local_1.valueDeclaration;
                                 if (compilerOptions.noUnusedParameters &&
                                     !ts.isParameterPropertyDeclaration(parameter) &&
-                                    !parameterIsThisKeyword(parameter) &&
                                     !parameterNameStartsWithUnderscore(parameter)) {
                                     error(local_1.valueDeclaration.name, ts.Diagnostics._0_is_declared_but_never_used, local_1.name);
                                 }
@@ -29380,9 +29356,6 @@ var ts;
                 }
             }
         }
-        function parameterIsThisKeyword(parameter) {
-            return parameter.name && parameter.name.originalKeywordKind === 97 /* ThisKeyword */;
-        }
         function parameterNameStartsWithUnderscore(parameter) {
             return parameter.name && parameter.name.kind === 69 /* Identifier */ && parameter.name.text.charCodeAt(0) === 95 /* _ */;
         }
@@ -29411,16 +29384,9 @@ var ts;
         function checkUnusedTypeParameters(node) {
             if (compilerOptions.noUnusedLocals && !ts.isInAmbientContext(node)) {
                 if (node.typeParameters) {
-                    // Only report errors on the last declaration for the type parameter container;
-                    // this ensures that all uses have been accounted for.
-                    var symbol = getSymbolOfNode(node);
-                    var lastDeclaration = symbol && symbol.declarations && ts.lastOrUndefined(symbol.declarations);
-                    if (lastDeclaration !== node) {
-                        return;
-                    }
                     for (var _i = 0, _a = node.typeParameters; _i < _a.length; _i++) {
                         var typeParameter = _a[_i];
-                        if (!getMergedSymbol(typeParameter.symbol).isReferenced) {
+                        if (!typeParameter.symbol.isReferenced) {
                             error(typeParameter.name, ts.Diagnostics._0_is_declared_but_never_used, typeParameter.symbol.name);
                         }
                     }
@@ -30753,7 +30719,7 @@ var ts;
             ts.forEach(node.members, checkSourceElement);
             if (produceDiagnostics) {
                 checkTypeForDuplicateIndexSignatures(node);
-                registerForUnusedIdentifiersCheck(node);
+                checkUnusedTypeParameters(node);
             }
         }
         function checkTypeAliasDeclaration(node) {
@@ -36017,7 +35983,7 @@ var ts;
                 writeLine();
                 var sourceMappingURL = sourceMap.getSourceMappingURL();
                 if (sourceMappingURL) {
-                    write("//# " + "sourceMappingURL" + "=" + sourceMappingURL); // Sometimes tools can sometimes see this line as a source mapping url comment
+                    write("//# sourceMappingURL=" + sourceMappingURL);
                 }
                 writeEmittedFiles(writer.getText(), jsFilePath, sourceMapFilePath, /*writeByteOrderMark*/ compilerOptions.emitBOM, sourceFiles);
                 // reset the state
@@ -37914,7 +37880,7 @@ var ts;
              *   if we should also export the value after its it changed
              * - check if node is a source level declaration to emit it differently,
              *   i.e non-exported variable statement 'var x = 1' is hoisted so
-             *   when we emit variable statement 'var' should be dropped.
+             *   we we emit variable statement 'var' should be dropped.
              */
             function isSourceFileLevelDeclarationInSystemJsModule(node, isExported) {
                 if (!node || !isCurrentFileSystemExternalModule()) {
@@ -40381,13 +40347,13 @@ var ts;
                         if (isES6ExportedDeclaration(node) && !(node.flags & 512 /* Default */) && decoratedClassAlias === undefined) {
                             write("export ");
                         }
+                        if (!isHoistedDeclarationInSystemModule) {
+                            write("let ");
+                        }
                         if (decoratedClassAlias !== undefined) {
-                            write("let " + decoratedClassAlias);
+                            write("" + decoratedClassAlias);
                         }
                         else {
-                            if (!isHoistedDeclarationInSystemModule) {
-                                write("let ");
-                            }
                             emitDeclarationName(node);
                         }
                         write(" = ");
@@ -40406,9 +40372,7 @@ var ts;
                 //
                 // We'll emit:
                 //
-                //      let C_1 = class C{};
-                //      C_1.a = 1;
-                //      C_1.b = 2; // so forth and so on
+                //      (_temp = class C { ... }, _temp.a = 1, _temp.b = 2, _temp)
                 //
                 // This keeps the expression as an expression, while ensuring that the static parts
                 // of it have been initialized by the time it is used.
@@ -42972,7 +42936,7 @@ var ts;
     /* @internal */ ts.ioReadTime = 0;
     /* @internal */ ts.ioWriteTime = 0;
     /** The version of the TypeScript compiler release */
-    ts.version = "2.1.0";
+    ts.version = "2.0.0";
     var emptyArray = [];
     var defaultTypeRoots = ["node_modules/@types"];
     function findConfigFile(searchPath, fileExists) {
@@ -43061,7 +43025,12 @@ var ts;
         return { resolvedModule: resolvedFileName ? { resolvedFileName: resolvedFileName, isExternalLibraryImport: isExternalLibraryImport } : undefined, failedLookupLocations: failedLookupLocations };
     }
     function moduleHasNonRelativeName(moduleName) {
-        return !(ts.isRootedDiskPath(moduleName) || ts.isExternalModuleNameRelative(moduleName));
+        if (ts.isRootedDiskPath(moduleName)) {
+            return false;
+        }
+        var i = moduleName.lastIndexOf("./", 1);
+        var startsWithDotSlashOrDotDotSlash = i === 0 || (i === 1 && moduleName.charCodeAt(0) === 46 /* dot */);
+        return !startsWithDotSlashOrDotDotSlash;
     }
     function tryReadTypesSection(packageJsonPath, baseDirectory, state) {
         var jsonContent;
@@ -43828,22 +43797,6 @@ var ts;
         return ts.sortAndDeduplicateDiagnostics(diagnostics);
     }
     ts.getPreEmitDiagnostics = getPreEmitDiagnostics;
-    function formatDiagnostics(diagnostics, host) {
-        var output = "";
-        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
-            var diagnostic = diagnostics_1[_i];
-            if (diagnostic.file) {
-                var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character;
-                var fileName = diagnostic.file.fileName;
-                var relativeFileName = ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); });
-                output += relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): ";
-            }
-            var category = ts.DiagnosticCategory[diagnostic.category].toLowerCase();
-            output += category + " TS" + diagnostic.code + ": " + flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) + host.getNewLine();
-        }
-        return output;
-    }
-    ts.formatDiagnostics = formatDiagnostics;
     function flattenDiagnosticMessageText(messageText, newLine) {
         if (typeof messageText === "string") {
             return messageText;
@@ -43936,11 +43889,11 @@ var ts;
         // As all these operations happen - and are nested - within the createProgram call, they close over the below variables.
         // The current resolution depth is tracked by incrementing/decrementing as the depth first search progresses.
         var maxNodeModulesJsDepth = typeof options.maxNodeModuleJsDepth === "number" ? options.maxNodeModuleJsDepth : 2;
-        var currentNodeModulesDepth = 0;
+        var currentNodeModulesJsDepth = 0;
         // If a module has some of its imports skipped due to being at the depth limit under node_modules, then track
         // this, as it may be imported at a shallower depth later, and then it will need its skipped imports processed.
         var modulesWithElidedImports = {};
-        // Track source files that are source files found by searching under node_modules, as these shouldn't be compiled.
+        // Track source files that are JavaScript files found by searching under node_modules, as these shouldn't be compiled.
         var sourceFilesFoundSearchingNodeModules = {};
         var start = new Date().getTime();
         host = host || createCompilerHost(options);
@@ -44197,7 +44150,8 @@ var ts;
             return noDiagnosticsTypeChecker || (noDiagnosticsTypeChecker = ts.createTypeChecker(program, /*produceDiagnostics:*/ false));
         }
         function emit(sourceFile, writeFileCallback, cancellationToken) {
-            return runWithCancellationToken(function () { return emitWorker(program, sourceFile, writeFileCallback, cancellationToken); });
+            var _this = this;
+            return runWithCancellationToken(function () { return emitWorker(_this, sourceFile, writeFileCallback, cancellationToken); });
         }
         function isEmitBlocked(emitFileName) {
             return hasEmitBlockingDiagnostics.contains(ts.toPath(emitFileName, currentDirectory, getCanonicalFileName));
@@ -44649,19 +44603,9 @@ var ts;
                 if (file_1 && options.forceConsistentCasingInFileNames && ts.getNormalizedAbsolutePath(file_1.fileName, currentDirectory) !== ts.getNormalizedAbsolutePath(fileName, currentDirectory)) {
                     reportFileNamesDifferOnlyInCasingError(fileName, file_1.fileName, refFile, refPos, refEnd);
                 }
-                // If the file was previously found via a node_modules search, but is now being processed as a root file,
-                // then everything it sucks in may also be marked incorrectly, and needs to be checked again.
-                if (file_1 && ts.lookUp(sourceFilesFoundSearchingNodeModules, file_1.path) && currentNodeModulesDepth == 0) {
-                    sourceFilesFoundSearchingNodeModules[file_1.path] = false;
-                    if (!options.noResolve) {
-                        processReferencedFiles(file_1, ts.getDirectoryPath(fileName), isDefaultLib);
-                        processTypeReferenceDirectives(file_1);
-                    }
-                    modulesWithElidedImports[file_1.path] = false;
-                    processImportedModules(file_1, ts.getDirectoryPath(fileName));
-                }
-                else if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
-                    if (currentNodeModulesDepth < maxNodeModulesJsDepth) {
+                // See if we need to reprocess the imports due to prior skipped imports
+                if (file_1 && ts.lookUp(modulesWithElidedImports, file_1.path)) {
+                    if (currentNodeModulesJsDepth < maxNodeModulesJsDepth) {
                         modulesWithElidedImports[file_1.path] = false;
                         processImportedModules(file_1, ts.getDirectoryPath(fileName));
                     }
@@ -44679,7 +44623,6 @@ var ts;
             });
             filesByName.set(path, file);
             if (file) {
-                sourceFilesFoundSearchingNodeModules[path] = (currentNodeModulesDepth > 0);
                 file.path = path;
                 if (host.useCaseSensitiveFileNames()) {
                     // for case-sensitive file systems check if we've already seen some file with similar filename ignoring case
@@ -44794,9 +44737,12 @@ var ts;
                     var isFromNodeModulesSearch = resolution && resolution.isExternalLibraryImport;
                     var isJsFileFromNodeModules = isFromNodeModulesSearch && ts.hasJavaScriptFileExtension(resolution.resolvedFileName);
                     if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth++;
+                        sourceFilesFoundSearchingNodeModules[resolvedPath] = true;
                     }
-                    var elideImport = isJsFileFromNodeModules && currentNodeModulesDepth > maxNodeModulesJsDepth;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth++;
+                    }
+                    var elideImport = isJsFileFromNodeModules && currentNodeModulesJsDepth > maxNodeModulesJsDepth;
                     var shouldAddFile = resolution && !options.noResolve && i < file.imports.length && !elideImport;
                     if (elideImport) {
                         modulesWithElidedImports[file.path] = true;
@@ -44805,8 +44751,8 @@ var ts;
                         findSourceFile(resolution.resolvedFileName, resolvedPath, 
                         /*isDefaultLib*/ false, /*isReference*/ false, file, ts.skipTrivia(file.text, file.imports[i].pos), file.imports[i].end);
                     }
-                    if (isFromNodeModulesSearch) {
-                        currentNodeModulesDepth--;
+                    if (isJsFileFromNodeModules) {
+                        currentNodeModulesJsDepth--;
                     }
                 }
             }
@@ -45144,12 +45090,12 @@ var ts;
         {
             name: "noUnusedLocals",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_locals
+            description: ts.Diagnostics.Report_Errors_on_Unused_Locals
         },
         {
             name: "noUnusedParameters",
             type: "boolean",
-            description: ts.Diagnostics.Report_errors_on_unused_parameters
+            description: ts.Diagnostics.Report_Errors_on_Unused_Parameters
         },
         {
             name: "noLib",
@@ -47141,7 +47087,7 @@ var ts;
                 else {
                     // b) Check if the part is a prefix of the candidate, in a case insensitive or sensitive
                     //    manner.  If it does, return that there was a prefix match.
-                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, /*isCaseSensitive:*/ ts.startsWith(candidate, chunk.text));
+                    return createPatternMatch(PatternMatchKind.prefix, punctuationStripped, /*isCaseSensitive:*/ startsWith(candidate, chunk.text));
                 }
             }
             var isLowercase = chunk.isLowerCase;
@@ -47407,6 +47353,14 @@ var ts;
         var str = String.fromCharCode(ch);
         return str === str.toLowerCase();
     }
+    function startsWith(string, search) {
+        for (var i = 0, n = search.length; i < n; i++) {
+            if (string.charCodeAt(i) !== search.charCodeAt(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
     // Assumes 'value' is already lowercase.
     function indexOfIgnoringCase(string, value) {
         for (var i = 0, n = string.length - value.length; i <= n; i++) {
@@ -49251,7 +49205,6 @@ var ts;
             ScanAction[ScanAction["RescanSlashToken"] = 2] = "RescanSlashToken";
             ScanAction[ScanAction["RescanTemplateToken"] = 3] = "RescanTemplateToken";
             ScanAction[ScanAction["RescanJsxIdentifier"] = 4] = "RescanJsxIdentifier";
-            ScanAction[ScanAction["RescanJsxText"] = 5] = "RescanJsxText";
         })(ScanAction || (ScanAction = {}));
         function getFormattingScanner(sourceFile, startPos, endPos) {
             ts.Debug.assert(scanner === undefined);
@@ -49343,9 +49296,6 @@ var ts;
                 }
                 return false;
             }
-            function shouldRescanJsxText(node) {
-                return node && node.kind === 244 /* JsxText */;
-            }
             function shouldRescanSlashToken(container) {
                 return container.kind === 10 /* RegularExpressionLiteral */;
             }
@@ -49376,9 +49326,7 @@ var ts;
                             ? 3 /* RescanTemplateToken */
                             : shouldRescanJsxIdentifier(n)
                                 ? 4 /* RescanJsxIdentifier */
-                                : shouldRescanJsxText(n)
-                                    ? 5 /* RescanJsxText */
-                                    : 0 /* Scan */;
+                                : 0 /* Scan */;
                 if (lastTokenInfo && expectedScanAction === lastScanAction) {
                     // readTokenInfo was called before with the same expected scan action.
                     // No need to re-scan text, return existing 'lastTokenInfo'
@@ -49413,10 +49361,6 @@ var ts;
                     currentToken = scanner.scanJsxIdentifier();
                     lastScanAction = 4 /* RescanJsxIdentifier */;
                 }
-                else if (expectedScanAction === 5 /* RescanJsxText */) {
-                    currentToken = scanner.reScanJsxToken();
-                    lastScanAction = 5 /* RescanJsxText */;
-                }
                 else {
                     lastScanAction = 0 /* Scan */;
                 }
@@ -52089,20 +52033,19 @@ var ts;
         "version"
     ];
     var jsDocCompletionEntries;
-    function createNode(kind, pos, end, parent) {
-        var node = kind >= 139 /* FirstNode */ ? new NodeObject(kind, pos, end) :
-            kind === 69 /* Identifier */ ? new IdentifierObject(kind, pos, end) :
-                new TokenObject(kind, pos, end);
+    function createNode(kind, pos, end, flags, parent) {
+        var node = new NodeObject(kind, pos, end);
+        node.flags = flags;
         node.parent = parent;
         return node;
     }
     var NodeObject = (function () {
         function NodeObject(kind, pos, end) {
+            this.kind = kind;
             this.pos = pos;
             this.end = end;
             this.flags = 0 /* None */;
             this.parent = undefined;
-            this.kind = kind;
         }
         NodeObject.prototype.getSourceFile = function () {
             return ts.getSourceFileOfNode(this);
@@ -52137,14 +52080,14 @@ var ts;
                 var token = useJSDocScanner ? scanner.scanJSDocToken() : scanner.scan();
                 var textPos = scanner.getTextPos();
                 if (textPos <= end) {
-                    nodes.push(createNode(token, pos, textPos, this));
+                    nodes.push(createNode(token, pos, textPos, 0, this));
                 }
                 pos = textPos;
             }
             return pos;
         };
         NodeObject.prototype.createSyntaxList = function (nodes) {
-            var list = createNode(282 /* SyntaxList */, nodes.pos, nodes.end, this);
+            var list = createNode(282 /* SyntaxList */, nodes.pos, nodes.end, 0, this);
             list._children = [];
             var pos = nodes.pos;
             for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
@@ -52230,74 +52173,6 @@ var ts;
         };
         return NodeObject;
     }());
-    var TokenOrIdentifierObject = (function () {
-        function TokenOrIdentifierObject(pos, end) {
-            // Set properties in same order as NodeObject
-            this.pos = pos;
-            this.end = end;
-            this.flags = 0 /* None */;
-            this.parent = undefined;
-        }
-        TokenOrIdentifierObject.prototype.getSourceFile = function () {
-            return ts.getSourceFileOfNode(this);
-        };
-        TokenOrIdentifierObject.prototype.getStart = function (sourceFile, includeJsDocComment) {
-            return ts.getTokenPosOfNode(this, sourceFile, includeJsDocComment);
-        };
-        TokenOrIdentifierObject.prototype.getFullStart = function () {
-            return this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getEnd = function () {
-            return this.end;
-        };
-        TokenOrIdentifierObject.prototype.getWidth = function (sourceFile) {
-            return this.getEnd() - this.getStart(sourceFile);
-        };
-        TokenOrIdentifierObject.prototype.getFullWidth = function () {
-            return this.end - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getLeadingTriviaWidth = function (sourceFile) {
-            return this.getStart(sourceFile) - this.pos;
-        };
-        TokenOrIdentifierObject.prototype.getFullText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.pos, this.end);
-        };
-        TokenOrIdentifierObject.prototype.getText = function (sourceFile) {
-            return (sourceFile || this.getSourceFile()).text.substring(this.getStart(), this.getEnd());
-        };
-        TokenOrIdentifierObject.prototype.getChildCount = function (sourceFile) {
-            return 0;
-        };
-        TokenOrIdentifierObject.prototype.getChildAt = function (index, sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getChildren = function (sourceFile) {
-            return emptyArray;
-        };
-        TokenOrIdentifierObject.prototype.getFirstToken = function (sourceFile) {
-            return undefined;
-        };
-        TokenOrIdentifierObject.prototype.getLastToken = function (sourceFile) {
-            return undefined;
-        };
-        return TokenOrIdentifierObject;
-    }());
-    var TokenObject = (function (_super) {
-        __extends(TokenObject, _super);
-        function TokenObject(kind, pos, end) {
-            _super.call(this, pos, end);
-            this.kind = kind;
-        }
-        return TokenObject;
-    }(TokenOrIdentifierObject));
-    var IdentifierObject = (function (_super) {
-        __extends(IdentifierObject, _super);
-        function IdentifierObject(kind, pos, end) {
-            _super.call(this, pos, end);
-        }
-        return IdentifierObject;
-    }(TokenOrIdentifierObject));
-    IdentifierObject.prototype.kind = 69 /* Identifier */;
     var SymbolObject = (function () {
         function SymbolObject(flags, name) {
             this.flags = flags;
@@ -59062,8 +58937,6 @@ var ts;
     function initializeServices() {
         ts.objectAllocator = {
             getNodeConstructor: function () { return NodeObject; },
-            getTokenConstructor: function () { return TokenObject; },
-            getIdentifierConstructor: function () { return IdentifierObject; },
             getSourceFileConstructor: function () { return SourceFileObject; },
             getSymbolConstructor: function () { return SymbolObject; },
             getTypeConstructor: function () { return TypeObject; },
@@ -59689,7 +59562,7 @@ var ts;
 //
 /// <reference path='services.ts' />
 /* @internal */
-var debugObjectHost = new Function("return this")();
+var debugObjectHost = this;
 // We need to use 'null' to interface with the managed side.
 /* tslint:disable:no-null-keyword */
 /* tslint:disable:no-in-operator */
@@ -59828,7 +59701,7 @@ var ts;
             return this.shimHost.getCurrentDirectory();
         };
         LanguageServiceShimHostAdapter.prototype.getDirectories = function (path) {
-            return JSON.parse(this.shimHost.getDirectories(path));
+            return this.shimHost.getDirectories(path);
         };
         LanguageServiceShimHostAdapter.prototype.getDefaultLibFileName = function (options) {
             return this.shimHost.getDefaultLibFileName(JSON.stringify(options));

package.json

@@ -75,6 +75,7 @@
         "through2": "latest",
         "travis-fold": "latest",
         "ts-node": "latest",
+        "tsd": "latest",
         "tslint": "next",
         "typescript": "next"
     },

scripts/browserify-optional.js

@@ -0,0 +1,24 @@
+// simple script to optionally elide source-map-support (or other optional modules) when running browserify.
+
+var stream = require("stream"),
+    Transform = stream.Transform,
+    resolve = require("browser-resolve");
+
+var requirePattern = /require\s*\(\s*['"](source-map-support)['"]\s*\)/;
+module.exports = function (file) {
+    return new Transform({
+        transform: function (data, encoding, cb) {
+            var text = encoding === "buffer" ? data.toString("utf8") : data;
+            this.push(new Buffer(text.replace(requirePattern, function (originalText, moduleName) {
+                try {
+                    resolve.sync(moduleName, { filename: file });
+                    return originalText;
+                }
+                catch (e) {
+                    return "(function () { throw new Error(\"module '" + moduleName + "' not found.\"); })()";
+                }
+            }), "utf8"));
+            cb();
+        }
+    });
+};

src/compiler/binder.ts

@@ -27,7 +27,7 @@ namespace ts {
             return ModuleInstanceState.ConstEnumOnly;
         }
         // 3. non-exported import declarations
-        else if ((node.kind === SyntaxKind.ImportDeclaration || node.kind === SyntaxKind.ImportEqualsDeclaration) && !(node.flags & NodeFlags.Export)) {
+        else if ((node.kind === SyntaxKind.ImportDeclaration || node.kind === SyntaxKind.ImportEqualsDeclaration) && !(hasModifier(node, ModifierFlags.Export))) {
             return ModuleInstanceState.NonInstantiated;
         }
         // 4. other uninstantiated module declarations.
@@ -131,6 +131,10 @@ namespace ts {
         const unreachableFlow: FlowNode = { flags: FlowFlags.Unreachable };
         const reportedUnreachableFlow: FlowNode = { flags: FlowFlags.Unreachable };
 
+        // state used to aggregate transform flags during bind.
+        let subtreeTransformFlags: TransformFlags = TransformFlags.None;
+        let skipTransformFlagAggregation: boolean;
+
         function bindSourceFile(f: SourceFile, opts: CompilerOptions) {
             file = f;
             options = opts;
@@ -138,6 +142,7 @@ namespace ts {
             inStrictMode = !!file.externalModuleIndicator;
             classifiableNames = createMap<string>();
             symbolCount = 0;
+            skipTransformFlagAggregation = isDeclarationFile(file);
 
             Symbol = objectAllocator.getSymbolConstructor();
 
@@ -164,6 +169,7 @@ namespace ts {
             activeLabels = undefined;
             hasExplicitReturn = false;
             emitFlags = NodeFlags.None;
+            subtreeTransformFlags = TransformFlags.None;
         }
 
         return bindSourceFile;
@@ -253,7 +259,7 @@ namespace ts {
 
                 case SyntaxKind.FunctionDeclaration:
                 case SyntaxKind.ClassDeclaration:
-                    return node.flags & NodeFlags.Default ? "default" : undefined;
+                    return hasModifier(node, ModifierFlags.Default) ? "default" : undefined;
                 case SyntaxKind.JSDocFunctionType:
                     return isJSDocConstructSignature(node) ? "__new" : "__call";
                 case SyntaxKind.Parameter:
@@ -293,7 +299,7 @@ namespace ts {
         function declareSymbol(symbolTable: SymbolTable, parent: Symbol, node: Declaration, includes: SymbolFlags, excludes: SymbolFlags): Symbol {
             Debug.assert(!hasDynamicName(node));
 
-            const isDefaultExport = node.flags & NodeFlags.Default;
+            const isDefaultExport = hasModifier(node, ModifierFlags.Default);
 
             // The exported symbol for an export default function/class node is always named "default"
             const name = isDefaultExport && parent ? "default" : getDeclarationName(node);
@@ -350,7 +356,7 @@ namespace ts {
                             : Diagnostics.Duplicate_identifier_0;
 
                         forEach(symbol.declarations, declaration => {
-                            if (declaration.flags & NodeFlags.Default) {
+                            if (hasModifier(declaration, ModifierFlags.Default)) {
                                 message = Diagnostics.A_module_cannot_have_multiple_default_exports;
                             }
                         });
@@ -372,7 +378,7 @@ namespace ts {
         }
 
         function declareModuleMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): Symbol {
-            const hasExportModifier = getCombinedNodeFlags(node) & NodeFlags.Export;
+            const hasExportModifier = getCombinedModifierFlags(node) & ModifierFlags.Export;
             if (symbolFlags & SymbolFlags.Alias) {
                 if (node.kind === SyntaxKind.ExportSpecifier || (node.kind === SyntaxKind.ImportEqualsDeclaration && hasExportModifier)) {
                     return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
@@ -513,6 +519,23 @@ namespace ts {
         }
 
         function bindChildren(node: Node): void {
+            if (skipTransformFlagAggregation) {
+                bindChildrenWorker(node);
+            }
+            else if (node.transformFlags & TransformFlags.HasComputedFlags) {
+                skipTransformFlagAggregation = true;
+                bindChildrenWorker(node);
+                skipTransformFlagAggregation = false;
+            }
+            else {
+                const savedSubtreeTransformFlags = subtreeTransformFlags;
+                subtreeTransformFlags = 0;
+                bindChildrenWorker(node);
+                subtreeTransformFlags = savedSubtreeTransformFlags | computeTransformFlagsForNode(node, subtreeTransformFlags);
+            }
+        }
+
+        function bindChildrenWorker(node: Node): void {
             // Binding of JsDocComment should be done before the current block scope container changes.
             // because the scope of JsDocComment should not be affected by whether the current node is a
             // container or not.
@@ -1308,7 +1331,7 @@ namespace ts {
         }
 
         function declareClassMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
-            return node.flags & NodeFlags.Static
+            return hasModifier(node, ModifierFlags.Static)
                 ? declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes)
                 : declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
         }
@@ -1345,7 +1368,7 @@ namespace ts {
         function bindModuleDeclaration(node: ModuleDeclaration) {
             setExportContextFlag(node);
             if (isAmbientModule(node)) {
-                if (node.flags & NodeFlags.Export) {
+                if (hasModifier(node, ModifierFlags.Export)) {
                     errorOnFirstToken(node, Diagnostics.export_modifier_cannot_be_applied_to_ambient_modules_and_module_augmentations_since_they_are_always_visible);
                 }
                 if (isExternalModuleAugmentation(node)) {
@@ -1612,7 +1635,7 @@ namespace ts {
             }
         }
 
-        function checkStrictModeNumericLiteral(node: LiteralExpression) {
+        function checkStrictModeNumericLiteral(node: NumericLiteral) {
             if (inStrictMode && node.isOctalLiteral) {
                 file.bindDiagnostics.push(createDiagnosticForNode(node, Diagnostics.Octal_literals_are_not_allowed_in_strict_mode));
             }
@@ -1687,6 +1710,9 @@ namespace ts {
                 }
                 parent = saveParent;
             }
+            else if (!skipTransformFlagAggregation && (node.transformFlags & TransformFlags.HasComputedFlags) === 0) {
+                subtreeTransformFlags |= computeTransformFlagsForNode(node, 0);
+            }
             inStrictMode = saveInStrictMode;
         }
 
@@ -1757,7 +1783,7 @@ namespace ts {
                 case SyntaxKind.DeleteExpression:
                     return checkStrictModeDeleteExpression(<DeleteExpression>node);
                 case SyntaxKind.NumericLiteral:
-                    return checkStrictModeNumericLiteral(<LiteralExpression>node);
+                    return checkStrictModeNumericLiteral(<NumericLiteral>node);
                 case SyntaxKind.PostfixUnaryExpression:
                     return checkStrictModePostfixUnaryExpression(<PostfixUnaryExpression>node);
                 case SyntaxKind.PrefixUnaryExpression:
@@ -1789,7 +1815,7 @@ namespace ts {
                     return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.EnumMember, SymbolFlags.EnumMemberExcludes);
 
                 case SyntaxKind.JsxSpreadAttribute:
-                    emitFlags |= NodeFlags.HasJsxSpreadAttribute;
+                    emitFlags |= NodeFlags.HasJsxSpreadAttributes;
                     return;
 
                 case SyntaxKind.CallSignature:
@@ -2204,7 +2230,7 @@ namespace ts {
             if (currentFlow === unreachableFlow) {
                 const reportError =
                     // report error on all statements except empty ones
-                    (isStatement(node) && node.kind !== SyntaxKind.EmptyStatement) ||
+                    (isStatementButNotDeclaration(node) && node.kind !== SyntaxKind.EmptyStatement) ||
                     // report error on class declarations
                     node.kind === SyntaxKind.ClassDeclaration ||
                     // report error on instantiated modules or const-enums only modules if preserveConstEnums is set
@@ -2241,4 +2267,763 @@ namespace ts {
             return true;
         }
     }
+
+    /**
+     * Computes the transform flags for a node, given the transform flags of its subtree
+     *
+     * @param node The node to analyze
+     * @param subtreeFlags Transform flags computed for this node's subtree
+     */
+    export function computeTransformFlagsForNode(node: Node, subtreeFlags: TransformFlags): TransformFlags {
+        const kind = node.kind;
+        switch (kind) {
+            case SyntaxKind.CallExpression:
+                return computeCallExpression(<CallExpression>node, subtreeFlags);
+
+            case SyntaxKind.ModuleDeclaration:
+                return computeModuleDeclaration(<ModuleDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.ParenthesizedExpression:
+                return computeParenthesizedExpression(<ParenthesizedExpression>node, subtreeFlags);
+
+            case SyntaxKind.BinaryExpression:
+                return computeBinaryExpression(<BinaryExpression>node, subtreeFlags);
+
+            case SyntaxKind.ExpressionStatement:
+                return computeExpressionStatement(<ExpressionStatement>node, subtreeFlags);
+
+            case SyntaxKind.Parameter:
+                return computeParameter(<ParameterDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.ArrowFunction:
+                return computeArrowFunction(<ArrowFunction>node, subtreeFlags);
+
+            case SyntaxKind.FunctionExpression:
+                return computeFunctionExpression(<FunctionExpression>node, subtreeFlags);
+
+            case SyntaxKind.FunctionDeclaration:
+                return computeFunctionDeclaration(<FunctionDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.VariableDeclaration:
+                return computeVariableDeclaration(<VariableDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.VariableDeclarationList:
+                return computeVariableDeclarationList(<VariableDeclarationList>node, subtreeFlags);
+
+            case SyntaxKind.VariableStatement:
+                return computeVariableStatement(<VariableStatement>node, subtreeFlags);
+
+            case SyntaxKind.LabeledStatement:
+                return computeLabeledStatement(<LabeledStatement>node, subtreeFlags);
+
+            case SyntaxKind.ClassDeclaration:
+                return computeClassDeclaration(<ClassDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.ClassExpression:
+                return computeClassExpression(<ClassExpression>node, subtreeFlags);
+
+            case SyntaxKind.HeritageClause:
+                return computeHeritageClause(<HeritageClause>node, subtreeFlags);
+
+            case SyntaxKind.ExpressionWithTypeArguments:
+                return computeExpressionWithTypeArguments(<ExpressionWithTypeArguments>node, subtreeFlags);
+
+            case SyntaxKind.Constructor:
+                return computeConstructor(<ConstructorDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.PropertyDeclaration:
+                return computePropertyDeclaration(<PropertyDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.MethodDeclaration:
+                return computeMethod(<MethodDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.GetAccessor:
+            case SyntaxKind.SetAccessor:
+                return computeAccessor(<AccessorDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.ImportEqualsDeclaration:
+                return computeImportEquals(<ImportEqualsDeclaration>node, subtreeFlags);
+
+            case SyntaxKind.PropertyAccessExpression:
+                return computePropertyAccess(<PropertyAccessExpression>node, subtreeFlags);
+
+            default:
+                return computeOther(node, kind, subtreeFlags);
+        }
+    }
+
+    function computeCallExpression(node: CallExpression, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const expression = node.expression;
+        const expressionKind = expression.kind;
+
+        if (subtreeFlags & TransformFlags.ContainsSpreadElementExpression
+            || isSuperOrSuperProperty(expression, expressionKind)) {
+            // If the this node contains a SpreadElementExpression, or is a super call, then it is an ES6
+            // node.
+            transformFlags |= TransformFlags.AssertES6;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ArrayLiteralOrCallOrNewExcludes;
+    }
+
+    function isSuperOrSuperProperty(node: Node, kind: SyntaxKind) {
+        switch (kind) {
+            case SyntaxKind.SuperKeyword:
+                return true;
+
+            case SyntaxKind.PropertyAccessExpression:
+            case SyntaxKind.ElementAccessExpression:
+                const expression = (<PropertyAccessExpression | ElementAccessExpression>node).expression;
+                const expressionKind = expression.kind;
+                return expressionKind === SyntaxKind.SuperKeyword;
+        }
+
+        return false;
+    }
+
+    function computeBinaryExpression(node: BinaryExpression, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const operatorTokenKind = node.operatorToken.kind;
+        const leftKind = node.left.kind;
+
+        if (operatorTokenKind === SyntaxKind.EqualsToken
+            && (leftKind === SyntaxKind.ObjectLiteralExpression
+                || leftKind === SyntaxKind.ArrayLiteralExpression)) {
+            // Destructuring assignments are ES6 syntax.
+            transformFlags |= TransformFlags.AssertES6 | TransformFlags.DestructuringAssignment;
+        }
+        else if (operatorTokenKind === SyntaxKind.AsteriskAsteriskToken
+            || operatorTokenKind === SyntaxKind.AsteriskAsteriskEqualsToken) {
+            // Exponentiation is ES7 syntax.
+            transformFlags |= TransformFlags.AssertES7;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeParameter(node: ParameterDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const modifierFlags = getModifierFlags(node);
+        const name = node.name;
+        const initializer = node.initializer;
+        const dotDotDotToken = node.dotDotDotToken;
+
+        // If the parameter has a question token, then it is TypeScript syntax.
+        if (node.questionToken) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        // If the parameter's name is 'this', then it is TypeScript syntax.
+        if (subtreeFlags & TransformFlags.ContainsDecorators
+            || (name && isIdentifier(name) && name.originalKeywordKind === SyntaxKind.ThisKeyword)) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        // If a parameter has an accessibility modifier, then it is TypeScript syntax.
+        if (modifierFlags & ModifierFlags.ParameterPropertyModifier) {
+            transformFlags |= TransformFlags.AssertTypeScript | TransformFlags.ContainsParameterPropertyAssignments;
+        }
+
+        // If a parameter has an initializer, a binding pattern or a dotDotDot token, then
+        // it is ES6 syntax and its container must emit default value assignments or parameter destructuring downlevel.
+        if (subtreeFlags & TransformFlags.ContainsBindingPattern || initializer || dotDotDotToken) {
+            transformFlags |= TransformFlags.AssertES6 | TransformFlags.ContainsDefaultValueAssignments;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ParameterExcludes;
+    }
+
+    function computeParenthesizedExpression(node: ParenthesizedExpression, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const expression = node.expression;
+        const expressionKind = expression.kind;
+        const expressionTransformFlags = expression.transformFlags;
+
+        // If the node is synthesized, it means the emitter put the parentheses there,
+        // not the user. If we didn't want them, the emitter would not have put them
+        // there.
+        if (expressionKind === SyntaxKind.AsExpression
+            || expressionKind === SyntaxKind.TypeAssertionExpression) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        // If the expression of a ParenthesizedExpression is a destructuring assignment,
+        // then the ParenthesizedExpression is a destructuring assignment.
+        if (expressionTransformFlags & TransformFlags.DestructuringAssignment) {
+            transformFlags |= TransformFlags.DestructuringAssignment;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeClassDeclaration(node: ClassDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags: TransformFlags;
+        const modifierFlags = getModifierFlags(node);
+
+        if (modifierFlags & ModifierFlags.Ambient) {
+            // An ambient declaration is TypeScript syntax.
+            transformFlags = TransformFlags.AssertTypeScript;
+        }
+        else {
+            // A ClassDeclaration is ES6 syntax.
+            transformFlags = subtreeFlags | TransformFlags.AssertES6;
+
+            // A class with a parameter property assignment, property initializer, or decorator is
+            // TypeScript syntax.
+            // An exported declaration may be TypeScript syntax.
+            if ((subtreeFlags & TransformFlags.TypeScriptClassSyntaxMask)
+                || (modifierFlags & ModifierFlags.Export)) {
+                transformFlags |= TransformFlags.AssertTypeScript;
+            }
+
+            if (subtreeFlags & TransformFlags.ContainsLexicalThisInComputedPropertyName) {
+                // A computed property name containing `this` might need to be rewritten,
+                // so propagate the ContainsLexicalThis flag upward.
+                transformFlags |= TransformFlags.ContainsLexicalThis;
+            }
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ClassExcludes;
+    }
+
+    function computeClassExpression(node: ClassExpression, subtreeFlags: TransformFlags) {
+        // A ClassExpression is ES6 syntax.
+        let transformFlags = subtreeFlags | TransformFlags.AssertES6;
+
+        // A class with a parameter property assignment, property initializer, or decorator is
+        // TypeScript syntax.
+        if (subtreeFlags & TransformFlags.TypeScriptClassSyntaxMask) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        if (subtreeFlags & TransformFlags.ContainsLexicalThisInComputedPropertyName) {
+            // A computed property name containing `this` might need to be rewritten,
+            // so propagate the ContainsLexicalThis flag upward.
+            transformFlags |= TransformFlags.ContainsLexicalThis;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ClassExcludes;
+    }
+
+    function computeHeritageClause(node: HeritageClause, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+
+        switch (node.token) {
+            case SyntaxKind.ExtendsKeyword:
+                // An `extends` HeritageClause is ES6 syntax.
+                transformFlags |= TransformFlags.AssertES6;
+                break;
+
+            case SyntaxKind.ImplementsKeyword:
+                // An `implements` HeritageClause is TypeScript syntax.
+                transformFlags |= TransformFlags.AssertTypeScript;
+                break;
+
+            default:
+                Debug.fail("Unexpected token for heritage clause");
+                break;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeExpressionWithTypeArguments(node: ExpressionWithTypeArguments, subtreeFlags: TransformFlags) {
+        // An ExpressionWithTypeArguments is ES6 syntax, as it is used in the
+        // extends clause of a class.
+        let transformFlags = subtreeFlags | TransformFlags.AssertES6;
+
+        // If an ExpressionWithTypeArguments contains type arguments, then it
+        // is TypeScript syntax.
+        if (node.typeArguments) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeConstructor(node: ConstructorDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const body = node.body;
+
+        if (body === undefined) {
+            // An overload constructor is TypeScript syntax.
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ConstructorExcludes;
+    }
+
+    function computeMethod(node: MethodDeclaration, subtreeFlags: TransformFlags) {
+        // A MethodDeclaration is ES6 syntax.
+        let transformFlags = subtreeFlags | TransformFlags.AssertES6;
+        const modifierFlags = getModifierFlags(node);
+        const body = node.body;
+        const typeParameters = node.typeParameters;
+        const asteriskToken = node.asteriskToken;
+
+        // A MethodDeclaration is TypeScript syntax if it is either async, abstract, overloaded,
+        // generic, or has a decorator.
+        if (!body
+            || typeParameters
+            || (modifierFlags & (ModifierFlags.Async | ModifierFlags.Abstract))
+            || (subtreeFlags & TransformFlags.ContainsDecorators)) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        // Currently, we only support generators that were originally async function bodies.
+        if (asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+            transformFlags |= TransformFlags.AssertGenerator;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.MethodOrAccessorExcludes;
+    }
+
+    function computeAccessor(node: AccessorDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const modifierFlags = getModifierFlags(node);
+        const body = node.body;
+
+        // A MethodDeclaration is TypeScript syntax if it is either async, abstract, overloaded,
+        // generic, or has a decorator.
+        if (!body
+            || (modifierFlags & (ModifierFlags.Async | ModifierFlags.Abstract))
+            || (subtreeFlags & TransformFlags.ContainsDecorators)) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.MethodOrAccessorExcludes;
+    }
+
+    function computePropertyDeclaration(node: PropertyDeclaration, subtreeFlags: TransformFlags) {
+        // A PropertyDeclaration is TypeScript syntax.
+        let transformFlags = subtreeFlags | TransformFlags.AssertTypeScript;
+
+        // If the PropertyDeclaration has an initializer, we need to inform its ancestor
+        // so that it handle the transformation.
+        if (node.initializer) {
+            transformFlags |= TransformFlags.ContainsPropertyInitializer;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeFunctionDeclaration(node: FunctionDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags: TransformFlags;
+        const modifierFlags = getModifierFlags(node);
+        const body = node.body;
+        const asteriskToken = node.asteriskToken;
+
+        if (!body || (modifierFlags & ModifierFlags.Ambient)) {
+            // An ambient declaration is TypeScript syntax.
+            // A FunctionDeclaration without a body is an overload and is TypeScript syntax.
+            transformFlags = TransformFlags.AssertTypeScript;
+        }
+        else {
+            transformFlags = subtreeFlags | TransformFlags.ContainsHoistedDeclarationOrCompletion;
+
+            // If a FunctionDeclaration is exported, then it is either ES6 or TypeScript syntax.
+            if (modifierFlags & ModifierFlags.Export) {
+                transformFlags |= TransformFlags.AssertTypeScript | TransformFlags.AssertES6;
+            }
+
+            // If a FunctionDeclaration is async, then it is TypeScript syntax.
+            if (modifierFlags & ModifierFlags.Async) {
+                transformFlags |= TransformFlags.AssertTypeScript;
+            }
+
+            // If a FunctionDeclaration's subtree has marked the container as needing to capture the
+            // lexical this, or the function contains parameters with initializers, then this node is
+            // ES6 syntax.
+            if (subtreeFlags & TransformFlags.ES6FunctionSyntaxMask) {
+                transformFlags |= TransformFlags.AssertES6;
+            }
+
+            // If a FunctionDeclaration is generator function and is the body of a
+            // transformed async function, then this node can be transformed to a
+            // down-level generator.
+            // Currently we do not support transforming any other generator fucntions
+            // down level.
+            if (asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+                transformFlags |= TransformFlags.AssertGenerator;
+            }
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.FunctionExcludes;
+    }
+
+    function computeFunctionExpression(node: FunctionExpression, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const modifierFlags = getModifierFlags(node);
+        const asteriskToken = node.asteriskToken;
+
+        // An async function expression is TypeScript syntax.
+        if (modifierFlags & ModifierFlags.Async) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        // If a FunctionExpression's subtree has marked the container as needing to capture the
+        // lexical this, or the function contains parameters with initializers, then this node is
+        // ES6 syntax.
+        if (subtreeFlags & TransformFlags.ES6FunctionSyntaxMask) {
+            transformFlags |= TransformFlags.AssertES6;
+        }
+
+        // If a FunctionExpression is generator function and is the body of a
+        // transformed async function, then this node can be transformed to a
+        // down-level generator.
+        // Currently we do not support transforming any other generator fucntions
+        // down level.
+        if (asteriskToken && node.emitFlags & NodeEmitFlags.AsyncFunctionBody) {
+            transformFlags |= TransformFlags.AssertGenerator;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.FunctionExcludes;
+    }
+
+    function computeArrowFunction(node: ArrowFunction, subtreeFlags: TransformFlags) {
+        // An ArrowFunction is ES6 syntax, and excludes markers that should not escape the scope of an ArrowFunction.
+        let transformFlags = subtreeFlags | TransformFlags.AssertES6;
+        const modifierFlags = getModifierFlags(node);
+
+        // An async arrow function is TypeScript syntax.
+        if (modifierFlags & ModifierFlags.Async) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        // If an ArrowFunction contains a lexical this, its container must capture the lexical this.
+        if (subtreeFlags & TransformFlags.ContainsLexicalThis) {
+            transformFlags |= TransformFlags.ContainsCapturedLexicalThis;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ArrowFunctionExcludes;
+    }
+
+    function computePropertyAccess(node: PropertyAccessExpression, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const expression = node.expression;
+        const expressionKind = expression.kind;
+
+        // If a PropertyAccessExpression starts with a super keyword, then it is
+        // ES6 syntax, and requires a lexical `this` binding.
+        if (expressionKind === SyntaxKind.SuperKeyword) {
+            transformFlags |= TransformFlags.ContainsLexicalThis;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeVariableDeclaration(node: VariableDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+        const nameKind = node.name.kind;
+
+        // A VariableDeclaration with a binding pattern is ES6 syntax.
+        if (nameKind === SyntaxKind.ObjectBindingPattern || nameKind === SyntaxKind.ArrayBindingPattern) {
+            transformFlags |= TransformFlags.AssertES6 | TransformFlags.ContainsBindingPattern;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeVariableStatement(node: VariableStatement, subtreeFlags: TransformFlags) {
+        let transformFlags: TransformFlags;
+        const modifierFlags = getModifierFlags(node);
+        const declarationListTransformFlags = node.declarationList.transformFlags;
+
+        // An ambient declaration is TypeScript syntax.
+        if (modifierFlags & ModifierFlags.Ambient) {
+            transformFlags = TransformFlags.AssertTypeScript;
+        }
+        else {
+            transformFlags = subtreeFlags;
+
+            // If a VariableStatement is exported, then it is either ES6 or TypeScript syntax.
+            if (modifierFlags & ModifierFlags.Export) {
+                transformFlags |= TransformFlags.AssertES6 | TransformFlags.AssertTypeScript;
+            }
+
+            if (declarationListTransformFlags & TransformFlags.ContainsBindingPattern) {
+                transformFlags |= TransformFlags.AssertES6;
+            }
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeLabeledStatement(node: LabeledStatement, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+
+        // A labeled statement containing a block scoped binding *may* need to be transformed from ES6.
+        if (subtreeFlags & TransformFlags.ContainsBlockScopedBinding
+            && isIterationStatement(node, /*lookInLabeledStatements*/ true)) {
+            transformFlags |= TransformFlags.AssertES6;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeImportEquals(node: ImportEqualsDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+
+        // An ImportEqualsDeclaration with a namespace reference is TypeScript.
+        if (!isExternalModuleImportEqualsDeclaration(node)) {
+            transformFlags |= TransformFlags.AssertTypeScript;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeExpressionStatement(node: ExpressionStatement, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags;
+
+        // If the expression of an expression statement is a destructuring assignment,
+        // then we treat the statement as ES6 so that we can indicate that we do not
+        // need to hold on to the right-hand side.
+        if (node.expression.transformFlags & TransformFlags.DestructuringAssignment) {
+            transformFlags |= TransformFlags.AssertES6;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.NodeExcludes;
+    }
+
+    function computeModuleDeclaration(node: ModuleDeclaration, subtreeFlags: TransformFlags) {
+        let transformFlags = TransformFlags.AssertTypeScript;
+        const modifierFlags = getModifierFlags(node);
+
+        if ((modifierFlags & ModifierFlags.Ambient) === 0) {
+            transformFlags |= subtreeFlags;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.ModuleExcludes;
+    }
+
+    function computeVariableDeclarationList(node: VariableDeclarationList, subtreeFlags: TransformFlags) {
+        let transformFlags = subtreeFlags | TransformFlags.ContainsHoistedDeclarationOrCompletion;
+
+        if (subtreeFlags & TransformFlags.ContainsBindingPattern) {
+            transformFlags |= TransformFlags.AssertES6;
+        }
+
+        // If a VariableDeclarationList is `let` or `const`, then it is ES6 syntax.
+        if (node.flags & NodeFlags.BlockScoped) {
+            transformFlags |= TransformFlags.AssertES6 | TransformFlags.ContainsBlockScopedBinding;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~TransformFlags.VariableDeclarationListExcludes;
+    }
+
+    function computeOther(node: Node, kind: SyntaxKind, subtreeFlags: TransformFlags) {
+        // Mark transformations needed for each node
+        let transformFlags = subtreeFlags;
+        let excludeFlags = TransformFlags.NodeExcludes;
+
+        switch (kind) {
+            case SyntaxKind.PublicKeyword:
+            case SyntaxKind.PrivateKeyword:
+            case SyntaxKind.ProtectedKeyword:
+            case SyntaxKind.AbstractKeyword:
+            case SyntaxKind.DeclareKeyword:
+            case SyntaxKind.AsyncKeyword:
+            case SyntaxKind.ConstKeyword:
+            case SyntaxKind.AwaitExpression:
+            case SyntaxKind.EnumDeclaration:
+            case SyntaxKind.EnumMember:
+            case SyntaxKind.TypeAssertionExpression:
+            case SyntaxKind.AsExpression:
+            case SyntaxKind.NonNullExpression:
+            case SyntaxKind.ReadonlyKeyword:
+                // These nodes are TypeScript syntax.
+                transformFlags |= TransformFlags.AssertTypeScript;
+                break;
+
+            case SyntaxKind.JsxElement:
+            case SyntaxKind.JsxSelfClosingElement:
+            case SyntaxKind.JsxOpeningElement:
+            case SyntaxKind.JsxText:
+            case SyntaxKind.JsxClosingElement:
+            case SyntaxKind.JsxAttribute:
+            case SyntaxKind.JsxSpreadAttribute:
+            case SyntaxKind.JsxExpression:
+                // These nodes are Jsx syntax.
+                transformFlags |= TransformFlags.AssertJsx;
+                break;
+
+            case SyntaxKind.ExportKeyword:
+                // This node is both ES6 and TypeScript syntax.
+                transformFlags |= TransformFlags.AssertES6 | TransformFlags.AssertTypeScript;
+                break;
+
+            case SyntaxKind.DefaultKeyword:
+            case SyntaxKind.NoSubstitutionTemplateLiteral:
+            case SyntaxKind.TemplateHead:
+            case SyntaxKind.TemplateMiddle:
+            case SyntaxKind.TemplateTail:
+            case SyntaxKind.TemplateExpression:
+            case SyntaxKind.TaggedTemplateExpression:
+            case SyntaxKind.ShorthandPropertyAssignment:
+            case SyntaxKind.ForOfStatement:
+                // These nodes are ES6 syntax.
+                transformFlags |= TransformFlags.AssertES6;
+                break;
+
+            case SyntaxKind.YieldExpression:
+                // This node is ES6 syntax.
+                transformFlags |= TransformFlags.AssertES6 | TransformFlags.ContainsYield;
+                break;
+
+            case SyntaxKind.AnyKeyword:
+            case SyntaxKind.NumberKeyword:
+            case SyntaxKind.NeverKeyword:
+            case SyntaxKind.StringKeyword:
+            case SyntaxKind.BooleanKeyword:
+            case SyntaxKind.SymbolKeyword:
+            case SyntaxKind.VoidKeyword:
+            case SyntaxKind.TypeParameter:
+            case SyntaxKind.PropertySignature:
+            case SyntaxKind.MethodSignature:
+            case SyntaxKind.CallSignature:
+            case SyntaxKind.ConstructSignature:
+            case SyntaxKind.IndexSignature:
+            case SyntaxKind.TypePredicate:
+            case SyntaxKind.TypeReference:
+            case SyntaxKind.FunctionType:
+            case SyntaxKind.ConstructorType:
+            case SyntaxKind.TypeQuery:
+            case SyntaxKind.TypeLiteral:
+            case SyntaxKind.ArrayType:
+            case SyntaxKind.TupleType:
+            case SyntaxKind.UnionType:
+            case SyntaxKind.IntersectionType:
+            case SyntaxKind.ParenthesizedType:
+            case SyntaxKind.InterfaceDeclaration:
+            case SyntaxKind.TypeAliasDeclaration:
+            case SyntaxKind.ThisType:
+            case SyntaxKind.LiteralType:
+                // Types and signatures are TypeScript syntax, and exclude all other facts.
+                transformFlags = TransformFlags.AssertTypeScript;
+                excludeFlags = TransformFlags.TypeExcludes;
+                break;
+
+            case SyntaxKind.ComputedPropertyName:
+                // Even though computed property names are ES6, we don't treat them as such.
+                // This is so that they can flow through PropertyName transforms unaffected.
+                // Instead, we mark the container as ES6, so that it can properly handle the transform.
+                transformFlags |= TransformFlags.ContainsComputedPropertyName;
+                if (subtreeFlags & TransformFlags.ContainsLexicalThis) {
+                    // A computed method name like `[this.getName()](x: string) { ... }` needs to
+                    // distinguish itself from the normal case of a method body containing `this`:
+                    // `this` inside a method doesn't need to be rewritten (the method provides `this`),
+                    // whereas `this` inside a computed name *might* need to be rewritten if the class/object
+                    // is inside an arrow function:
+                    // `_this = this; () => class K { [_this.getName()]() { ... } }`
+                    // To make this distinction, use ContainsLexicalThisInComputedPropertyName
+                    // instead of ContainsLexicalThis for computed property names
+                    transformFlags |= TransformFlags.ContainsLexicalThisInComputedPropertyName;
+                }
+                break;
+
+            case SyntaxKind.SpreadElementExpression:
+                // This node is ES6 syntax, but is handled by a containing node.
+                transformFlags |= TransformFlags.ContainsSpreadElementExpression;
+                break;
+
+            case SyntaxKind.SuperKeyword:
+                // This node is ES6 syntax.
+                transformFlags |= TransformFlags.AssertES6;
+                break;
+
+            case SyntaxKind.ThisKeyword:
+                // Mark this node and its ancestors as containing a lexical `this` keyword.
+                transformFlags |= TransformFlags.ContainsLexicalThis;
+                break;
+
+            case SyntaxKind.ObjectBindingPattern:
+            case SyntaxKind.ArrayBindingPattern:
+                // These nodes are ES6 syntax.
+                transformFlags |= TransformFlags.AssertES6 | TransformFlags.ContainsBindingPattern;
+                break;
+
+            case SyntaxKind.Decorator:
+                // This node is TypeScript syntax, and marks its container as also being TypeScript syntax.
+                transformFlags |= TransformFlags.AssertTypeScript | TransformFlags.ContainsDecorators;
+                break;
+
+            case SyntaxKind.ObjectLiteralExpression:
+                excludeFlags = TransformFlags.ObjectLiteralExcludes;
+                if (subtreeFlags & TransformFlags.ContainsComputedPropertyName) {
+                    // If an ObjectLiteralExpression contains a ComputedPropertyName, then it
+                    // is an ES6 node.
+                    transformFlags |= TransformFlags.AssertES6;
+                }
+
+                if (subtreeFlags & TransformFlags.ContainsLexicalThisInComputedPropertyName) {
+                    // A computed property name containing `this` might need to be rewritten,
+                    // so propagate the ContainsLexicalThis flag upward.
+                    transformFlags |= TransformFlags.ContainsLexicalThis;
+                }
+
+                break;
+
+            case SyntaxKind.ArrayLiteralExpression:
+            case SyntaxKind.NewExpression:
+                excludeFlags = TransformFlags.ArrayLiteralOrCallOrNewExcludes;
+                if (subtreeFlags & TransformFlags.ContainsSpreadElementExpression) {
+                    // If the this node contains a SpreadElementExpression, then it is an ES6
+                    // node.
+                    transformFlags |= TransformFlags.AssertES6;
+                }
+
+                break;
+
+            case SyntaxKind.DoStatement:
+            case SyntaxKind.WhileStatement:
+            case SyntaxKind.ForStatement:
+            case SyntaxKind.ForInStatement:
+                // A loop containing a block scoped binding *may* need to be transformed from ES6.
+                if (subtreeFlags & TransformFlags.ContainsBlockScopedBinding) {
+                    transformFlags |= TransformFlags.AssertES6;
+                }
+
+                break;
+
+            case SyntaxKind.SourceFile:
+                if (subtreeFlags & TransformFlags.ContainsCapturedLexicalThis) {
+                    transformFlags |= TransformFlags.AssertES6;
+                }
+
+                break;
+
+            case SyntaxKind.ReturnStatement:
+            case SyntaxKind.ContinueStatement:
+            case SyntaxKind.BreakStatement:
+                transformFlags |= TransformFlags.ContainsHoistedDeclarationOrCompletion;
+                break;
+        }
+
+        node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
+        return transformFlags & ~excludeFlags;
+    }
 }

src/compiler/commandLineParser.ts

@@ -30,6 +30,7 @@ namespace ts {
         {
             name: "extendedDiagnostics",
             type: "boolean",
+            experimental: true
         },
         {
             name: "emitBOM",
@@ -433,6 +434,11 @@ namespace ts {
             name: "strictNullChecks",
             type: "boolean",
             description: Diagnostics.Enable_strict_null_checks
+        },
+        {
+            name: "importHelpers",
+            type: "boolean",
+            description: Diagnostics.Import_emit_helpers_from_tslib
         }
     ];
 

src/compiler/comments.ts

@@ -0,0 +1,352 @@
+/// <reference path="sourcemap.ts" />
+
+/* @internal */
+namespace ts {
+    export interface CommentWriter {
+        reset(): void;
+        setSourceFile(sourceFile: SourceFile): void;
+        emitNodeWithComments(node: Node, emitCallback: (node: Node) => void): void;
+        emitBodyWithDetachedComments(node: Node, detachedRange: TextRange, emitCallback: (node: Node) => void): void;
+        emitTrailingCommentsOfPosition(pos: number): void;
+    }
+
+    export function createCommentWriter(host: EmitHost, writer: EmitTextWriter, sourceMap: SourceMapWriter): CommentWriter {
+        const compilerOptions = host.getCompilerOptions();
+        const extendedDiagnostics = compilerOptions.extendedDiagnostics;
+        const newLine = host.getNewLine();
+        const { emitPos } = sourceMap;
+
+        let containerPos = -1;
+        let containerEnd = -1;
+        let declarationListContainerEnd = -1;
+        let currentSourceFile: SourceFile;
+        let currentText: string;
+        let currentLineMap: number[];
+        let detachedCommentsInfo: { nodePos: number, detachedCommentEndPos: number}[];
+        let hasWrittenComment = false;
+        let disabled: boolean = compilerOptions.removeComments;
+
+        return {
+            reset,
+            setSourceFile,
+            emitNodeWithComments,
+            emitBodyWithDetachedComments,
+            emitTrailingCommentsOfPosition,
+        };
+
+        function emitNodeWithComments(node: Node, emitCallback: (node: Node) => void) {
+            if (disabled) {
+                emitCallback(node);
+                return;
+            }
+
+            if (node) {
+                const { pos, end } = node.commentRange || node;
+                const emitFlags = node.emitFlags;
+                if ((pos < 0 && end < 0) || (pos === end)) {
+                    // Both pos and end are synthesized, so just emit the node without comments.
+                    if (emitFlags & NodeEmitFlags.NoNestedComments) {
+                        disableCommentsAndEmit(node, emitCallback);
+                    }
+                    else {
+                        emitCallback(node);
+                    }
+                }
+                else {
+                    if (extendedDiagnostics) {
+                        performance.mark("preEmitNodeWithComment");
+                    }
+
+                    const isEmittedNode = node.kind !== SyntaxKind.NotEmittedStatement;
+                    const skipLeadingComments = pos < 0 || (emitFlags & NodeEmitFlags.NoLeadingComments) !== 0;
+                    const skipTrailingComments = end < 0 || (emitFlags & NodeEmitFlags.NoTrailingComments) !== 0;
+
+                    // Emit leading comments if the position is not synthesized and the node
+                    // has not opted out from emitting leading comments.
+                    if (!skipLeadingComments) {
+                        emitLeadingComments(pos, isEmittedNode);
+                    }
+
+                    // Save current container state on the stack.
+                    const savedContainerPos = containerPos;
+                    const savedContainerEnd = containerEnd;
+                    const savedDeclarationListContainerEnd = declarationListContainerEnd;
+
+                    if (!skipLeadingComments) {
+                        containerPos = pos;
+                    }
+
+                    if (!skipTrailingComments) {
+                        containerEnd = end;
+
+                        // To avoid invalid comment emit in a down-level binding pattern, we
+                        // keep track of the last declaration list container's end
+                        if (node.kind === SyntaxKind.VariableDeclarationList) {
+                            declarationListContainerEnd = end;
+                        }
+                    }
+
+                    if (extendedDiagnostics) {
+                        performance.measure("commentTime", "preEmitNodeWithComment");
+                    }
+
+                    if (emitFlags & NodeEmitFlags.NoNestedComments) {
+                        disableCommentsAndEmit(node, emitCallback);
+                    }
+                    else {
+                        emitCallback(node);
+                    }
+
+                    if (extendedDiagnostics) {
+                        performance.mark("beginEmitNodeWithComment");
+                    }
+
+                    // Restore previous container state.
+                    containerPos = savedContainerPos;
+                    containerEnd = savedContainerEnd;
+                    declarationListContainerEnd = savedDeclarationListContainerEnd;
+
+                    // Emit trailing comments if the position is not synthesized and the node
+                    // has not opted out from emitting leading comments and is an emitted node.
+                    if (!skipTrailingComments && isEmittedNode) {
+                        emitTrailingComments(end);
+                    }
+
+                    if (extendedDiagnostics) {
+                        performance.measure("commentTime", "beginEmitNodeWithComment");
+                    }
+                }
+            }
+        }
+
+        function emitBodyWithDetachedComments(node: Node, detachedRange: TextRange, emitCallback: (node: Node) => void) {
+            if (extendedDiagnostics) {
+                performance.mark("preEmitBodyWithDetachedComments");
+            }
+
+            const { pos, end } = detachedRange;
+            const emitFlags = node.emitFlags;
+            const skipLeadingComments = pos < 0 || (emitFlags & NodeEmitFlags.NoLeadingComments) !== 0;
+            const skipTrailingComments = disabled || end < 0 || (emitFlags & NodeEmitFlags.NoTrailingComments) !== 0;
+
+            if (!skipLeadingComments) {
+                emitDetachedCommentsAndUpdateCommentsInfo(detachedRange);
+            }
+
+            if (extendedDiagnostics) {
+                performance.measure("commentTime", "preEmitBodyWithDetachedComments");
+            }
+
+            if (emitFlags & NodeEmitFlags.NoNestedComments) {
+                disableCommentsAndEmit(node, emitCallback);
+            }
+            else {
+                emitCallback(node);
+            }
+
+            if (extendedDiagnostics) {
+                performance.mark("beginEmitBodyWithDetachedCommetns");
+            }
+
+            if (!skipTrailingComments) {
+                emitLeadingComments(detachedRange.end, /*isEmittedNode*/ true);
+            }
+
+            if (extendedDiagnostics) {
+                performance.measure("commentTime", "beginEmitBodyWithDetachedCommetns");
+            }
+        }
+
+        function emitLeadingComments(pos: number, isEmittedNode: boolean) {
+            hasWrittenComment = false;
+
+            if (isEmittedNode) {
+                forEachLeadingCommentToEmit(pos, emitLeadingComment);
+            }
+            else if (pos === 0) {
+                // If the node will not be emitted in JS, remove all the comments(normal, pinned and ///) associated with the node,
+                // unless it is a triple slash comment at the top of the file.
+                // For Example:
+                //      /// <reference-path ...>
+                //      declare var x;
+                //      /// <reference-path ...>
+                //      interface F {}
+                //  The first /// will NOT be removed while the second one will be removed even though both node will not be emitted
+                forEachLeadingCommentToEmit(pos, emitTripleSlashLeadingComment);
+            }
+        }
+
+        function emitTripleSlashLeadingComment(commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean, rangePos: number) {
+            if (isTripleSlashComment(commentPos, commentEnd)) {
+                emitLeadingComment(commentPos, commentEnd, kind, hasTrailingNewLine, rangePos);
+            }
+        }
+
+        function emitLeadingComment(commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean, rangePos: number) {
+            if (!hasWrittenComment) {
+                emitNewLineBeforeLeadingCommentOfPosition(currentLineMap, writer, rangePos, commentPos);
+                hasWrittenComment = true;
+            }
+
+            // Leading comments are emitted at /*leading comment1 */space/*leading comment*/space
+            emitPos(commentPos);
+            writeCommentRange(currentText, currentLineMap, writer, commentPos, commentEnd, newLine);
+            emitPos(commentEnd);
+
+            if (hasTrailingNewLine) {
+                writer.writeLine();
+            }
+            else {
+                writer.write(" ");
+            }
+        }
+
+        function emitTrailingComments(pos: number) {
+            forEachTrailingCommentToEmit(pos, emitTrailingComment);
+        }
+
+        function emitTrailingComment(commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean) {
+            // trailing comments are emitted at space/*trailing comment1 */space/*trailing comment2*/
+            if (!writer.isAtStartOfLine()) {
+                writer.write(" ");
+            }
+
+            emitPos(commentPos);
+            writeCommentRange(currentText, currentLineMap, writer, commentPos, commentEnd, newLine);
+            emitPos(commentEnd);
+
+            if (hasTrailingNewLine) {
+                writer.writeLine();
+            }
+        }
+
+        function emitTrailingCommentsOfPosition(pos: number) {
+            if (disabled) {
+                return;
+            }
+
+            if (extendedDiagnostics) {
+                performance.mark("beforeEmitTrailingCommentsOfPosition");
+            }
+
+            forEachTrailingCommentToEmit(pos, emitTrailingCommentOfPosition);
+
+            if (extendedDiagnostics) {
+                performance.measure("commentTime", "beforeEmitTrailingCommentsOfPosition");
+            }
+        }
+
+        function emitTrailingCommentOfPosition(commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean) {
+            // trailing comments of a position are emitted at /*trailing comment1 */space/*trailing comment*/space
+
+            emitPos(commentPos);
+            writeCommentRange(currentText, currentLineMap, writer, commentPos, commentEnd, newLine);
+            emitPos(commentEnd);
+
+            if (hasTrailingNewLine) {
+                writer.writeLine();
+            }
+            else {
+                writer.write(" ");
+            }
+        }
+
+        function forEachLeadingCommentToEmit(pos: number, cb: (commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean, rangePos: number) => void) {
+            // Emit the leading comments only if the container's pos doesn't match because the container should take care of emitting these comments
+            if (containerPos === -1 || pos !== containerPos) {
+                if (hasDetachedComments(pos)) {
+                    forEachLeadingCommentWithoutDetachedComments(cb);
+                }
+                else {
+                    forEachLeadingCommentRange(currentText, pos, cb, /*state*/ pos);
+                }
+            }
+        }
+
+        function forEachTrailingCommentToEmit(end: number, cb: (commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean) => void) {
+            // Emit the trailing comments only if the container's end doesn't match because the container should take care of emitting these comments
+            if (containerEnd === -1 || (end !== containerEnd && end !== declarationListContainerEnd)) {
+                forEachTrailingCommentRange(currentText, end, cb);
+            }
+        }
+
+        function reset() {
+            currentSourceFile = undefined;
+            currentText = undefined;
+            currentLineMap = undefined;
+            detachedCommentsInfo = undefined;
+        }
+
+        function setSourceFile(sourceFile: SourceFile) {
+            currentSourceFile = sourceFile;
+            currentText = currentSourceFile.text;
+            currentLineMap = getLineStarts(currentSourceFile);
+            detachedCommentsInfo = undefined;
+        }
+
+        function disableCommentsAndEmit(node: Node, emitCallback: (node: Node) => void): void {
+            if (disabled) {
+                emitCallback(node);
+            }
+            else {
+                disabled = true;
+                emitCallback(node);
+                disabled = false;
+            }
+        }
+
+        function hasDetachedComments(pos: number) {
+            return detachedCommentsInfo !== undefined && lastOrUndefined(detachedCommentsInfo).nodePos === pos;
+        }
+
+        function forEachLeadingCommentWithoutDetachedComments(cb: (commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean, rangePos: number) => void) {
+            // get the leading comments from detachedPos
+            const pos = lastOrUndefined(detachedCommentsInfo).detachedCommentEndPos;
+            if (detachedCommentsInfo.length - 1) {
+                detachedCommentsInfo.pop();
+            }
+            else {
+                detachedCommentsInfo = undefined;
+            }
+
+            forEachLeadingCommentRange(currentText, pos, cb, /*state*/ pos);
+        }
+
+        function emitDetachedCommentsAndUpdateCommentsInfo(range: TextRange) {
+            const currentDetachedCommentInfo = emitDetachedComments(currentText, currentLineMap, writer, writeComment, range, newLine, disabled);
+            if (currentDetachedCommentInfo) {
+                if (detachedCommentsInfo) {
+                    detachedCommentsInfo.push(currentDetachedCommentInfo);
+                }
+                else {
+                    detachedCommentsInfo = [currentDetachedCommentInfo];
+                }
+            }
+        }
+
+        function writeComment(text: string, lineMap: number[], writer: EmitTextWriter, commentPos: number, commentEnd: number, newLine: string) {
+            emitPos(commentPos);
+            writeCommentRange(text, lineMap, writer, commentPos, commentEnd, newLine);
+            emitPos(commentEnd);
+        }
+
+        /**
+         * Determine if the given comment is a triple-slash
+         *
+         * @return true if the comment is a triple-slash comment else false
+         **/
+        function isTripleSlashComment(commentPos: number, commentEnd: number) {
+            // Verify this is /// comment, but do the regexp match only when we first can find /// in the comment text
+            // so that we don't end up computing comment string and doing match for all // comments
+            if (currentText.charCodeAt(commentPos + 1) === CharacterCodes.slash &&
+                commentPos + 2 < commentEnd &&
+                currentText.charCodeAt(commentPos + 2) === CharacterCodes.slash) {
+                const textSubStr = currentText.substring(commentPos, commentEnd);
+                return textSubStr.match(fullTripleSlashReferencePathRegEx) ||
+                    textSubStr.match(fullTripleSlashAMDReferencePathRegEx) ?
+                    true : false;
+            }
+            return false;
+        }
+    }
+}

src/compiler/core.ts

@@ -113,6 +113,23 @@ namespace ts {
         return undefined;
     }
 
+    /**
+     * Iterates through `array` by index and performs the callback on each element of array until the callback
+     * returns a falsey value, then returns false.
+     * If no such value is found, the callback is applied to each element of array and `true` is returned.
+     */
+    export function every<T>(array: T[], callback: (element: T, index: number) => boolean): boolean {
+        if (array) {
+            for (let i = 0, len = array.length; i < len; i++) {
+                if (!callback(array[i], i)) {
+                    return false;
+                }
+            }
+        }
+
+        return true;
+    }
+
     /** Works like Array.prototype.find, returning `undefined` if no element satisfying the predicate is found. */
     export function find<T>(array: T[], predicate: (element: T, index: number) => boolean): T | undefined {
         for (let i = 0, len = array.length; i < len; i++) {
@@ -169,11 +186,12 @@ namespace ts {
         return -1;
     }
 
-    export function countWhere<T>(array: T[], predicate: (x: T) => boolean): number {
+    export function countWhere<T>(array: T[], predicate: (x: T, i: number) => boolean): number {
         let count = 0;
         if (array) {
-            for (const v of array) {
-                if (predicate(v)) {
+            for (let i = 0; i < array.length; i++) {
+                const v = array[i];
+                if (predicate(v, i)) {
                     count++;
                 }
             }
@@ -185,6 +203,8 @@ namespace ts {
      * Filters an array by a predicate function. Returns the same array instance if the predicate is
      * true for all elements, otherwise returns a new array instance containing the filtered subset.
      */
+    export function filter<T, U extends T>(array: T[], f: (x: T) => x is U): U[];
+    export function filter<T>(array: T[], f: (x: T) => boolean): T[]
     export function filter<T>(array: T[], f: (x: T) => boolean): T[] {
         if (array) {
             const len = array.length;
@@ -232,22 +252,135 @@ namespace ts {
         array.length = outIndex;
     }
 
-    export function map<T, U>(array: T[], f: (x: T) => U): U[] {
+    export function map<T, U>(array: T[], f: (x: T, i: number) => U): U[] {
         let result: U[];
         if (array) {
             result = [];
-            for (const v of array) {
-                result.push(f(v));
+            for (let i = 0; i < array.length; i++) {
+                const v = array[i];
+                result.push(f(v, i));
             }
         }
         return result;
     }
 
+    /**
+     * Flattens an array containing a mix of array or non-array elements.
+     *
+     * @param array The array to flatten.
+     */
+    export function flatten<T>(array: (T | T[])[]): T[] {
+        let result: T[];
+        if (array) {
+            result = [];
+            for (const v of array) {
+                if (v) {
+                    if (isArray(v)) {
+                        addRange(result, v);
+                    }
+                    else {
+                        result.push(v);
+                    }
+                }
+            }
+        }
+
+        return result;
+    }
+
+    /**
+     * Maps an array. If the mapped value is an array, it is spread into the result.
+     *
+     * @param array The array to map.
+     * @param mapfn The callback used to map the result into one or more values.
+     */
+    export function flatMap<T, U>(array: T[], mapfn: (x: T, i: number) => U | U[]): U[] {
+        let result: U[];
+        if (array) {
+            result = [];
+            for (let i = 0; i < array.length; i++) {
+                const v = mapfn(array[i], i);
+                if (v) {
+                    if (isArray(v)) {
+                        addRange(result, v);
+                    }
+                    else {
+                        result.push(v);
+                    }
+                }
+            }
+        }
+        return result;
+    }
+
+    /**
+     * Computes the first matching span of elements and returns a tuple of the first span
+     * and the remaining elements.
+     */
+    export function span<T>(array: T[], f: (x: T, i: number) => boolean): [T[], T[]] {
+        if (array) {
+            for (let i = 0; i < array.length; i++) {
+                if (!f(array[i], i)) {
+                    return [array.slice(0, i), array.slice(i)];
+                }
+            }
+            return [array.slice(0), []];
+        }
+
+        return undefined;
+    }
+
+    /**
+     * Maps contiguous spans of values with the same key.
+     *
+     * @param array The array to map.
+     * @param keyfn A callback used to select the key for an element.
+     * @param mapfn A callback used to map a contiguous chunk of values to a single value.
+     */
+    export function spanMap<T, K, U>(array: T[], keyfn: (x: T, i: number) => K, mapfn: (chunk: T[], key: K, start: number, end: number) => U): U[] {
+        let result: U[];
+        if (array) {
+            result = [];
+            const len = array.length;
+            let previousKey: K;
+            let key: K;
+            let start = 0;
+            let pos = 0;
+            while (start < len) {
+                while (pos < len) {
+                    const value = array[pos];
+                    key = keyfn(value, pos);
+                    if (pos === 0) {
+                        previousKey = key;
+                    }
+                    else if (key !== previousKey) {
+                        break;
+                    }
+
+                    pos++;
+                }
+
+                if (start < pos) {
+                    const v = mapfn(array.slice(start, pos), previousKey, start, pos);
+                    if (v) {
+                        result.push(v);
+                    }
+
+                    start = pos;
+                }
+
+                previousKey = key;
+                pos++;
+            }
+        }
+
+        return result;
+    }
+
     export function concatenate<T>(array1: T[], array2: T[]): T[] {
         if (!array2 || !array2.length) return array1;
         if (!array1 || !array1.length) return array2;
-
-        return array1.concat(array2);
+        return [...array1, ...array2];
     }
 
     export function deduplicate<T>(array: T[], areEqual?: (a: T, b: T) => boolean): T[] {
@@ -266,6 +399,27 @@ namespace ts {
         return result;
     }
 
+    /**
+     * Compacts an array, removing any falsey elements.
+     */
+    export function compact<T>(array: T[]): T[] {
+        let result: T[];
+        if (array) {
+            for (let i = 0; i < array.length; i++) {
+                const v = array[i];
+                if (result || !v) {
+                    if (!result) {
+                        result = array.slice(0, i);
+                    }
+                    if (v) {
+                        result.push(v);
+                    }
+                }
+            }
+        }
+        return result || array;
+    }
+
     export function sum(array: any[], prop: string): number {
         let result = 0;
         for (const v of array) {
@@ -277,7 +431,9 @@ namespace ts {
     export function addRange<T>(to: T[], from: T[]): void {
         if (to && from) {
             for (const v of from) {
-                to.push(v);
+                if (v !== undefined) {
+                    to.push(v);
+                }
             }
         }
     }
@@ -292,15 +448,31 @@ namespace ts {
         return true;
     }
 
+    export function firstOrUndefined<T>(array: T[]): T {
+        return array && array.length > 0
+            ? array[0]
+            : undefined;
+    }
+
+    export function singleOrUndefined<T>(array: T[]): T {
+        return array && array.length === 1
+            ? array[0]
+            : undefined;
+    }
+
+    export function singleOrMany<T>(array: T[]): T | T[] {
+        return array && array.length === 1
+            ? array[0]
+            : array;
+    }
+
     /**
      * Returns the last element of an array if non-empty, undefined otherwise.
      */
     export function lastOrUndefined<T>(array: T[]): T {
-        if (array.length === 0) {
-            return undefined;
-        }
-
-        return array[array.length - 1];
+        return array && array.length > 0
+            ? array[array.length - 1]
+            : undefined;
     }
 
     /**
@@ -332,14 +504,15 @@ namespace ts {
         return ~low;
     }
 
-    export function reduceLeft<T>(array: T[], f: (a: T, x: T) => T): T;
-    export function reduceLeft<T, U>(array: T[], f: (a: U, x: T) => U, initial: U): U;
-    export function reduceLeft<T, U>(array: T[], f: (a: U, x: T) => U, initial?: U): U {
-        if (array) {
-            const count = array.length;
-            if (count > 0) {
-                let pos = 0;
-                let result: T | U;
+    export function reduceLeft<T, U>(array: T[], f: (memo: U, value: T, i: number) => U, initial: U, start?: number, count?: number): U;
+    export function reduceLeft<T>(array: T[], f: (memo: T, value: T, i: number) => T): T;
+    export function reduceLeft<T>(array: T[], f: (memo: T, value: T, i: number) => T, initial?: T, start?: number, count?: number): T {
+        if (array && array.length > 0) {
+            const size = array.length;
+            if (size > 0) {
+                let pos = start === undefined || start < 0 ? 0 : start;
+                const end = count === undefined || pos + count > size - 1 ? size - 1 : pos + count;
+                let result: T;
                 if (arguments.length <= 2) {
                     result = array[pos];
                     pos++;
@@ -347,23 +520,25 @@ namespace ts {
                 else {
                     result = initial;
                 }
-                while (pos < count) {
-                    result = f(<U>result, array[pos]);
+                while (pos <= end) {
+                    result = f(result, array[pos], pos);
                     pos++;
                 }
-                return <U>result;
+                return result;
             }
         }
         return initial;
     }
 
-    export function reduceRight<T>(array: T[], f: (a: T, x: T) => T): T;
-    export function reduceRight<T, U>(array: T[], f: (a: U, x: T) => U, initial: U): U;
-    export function reduceRight<T, U>(array: T[], f: (a: U, x: T) => U, initial?: U): U {
+    export function reduceRight<T, U>(array: T[], f: (memo: U, value: T, i: number) => U, initial: U, start?: number, count?: number): U;
+    export function reduceRight<T>(array: T[], f: (memo: T, value: T, i: number) => T): T;
+    export function reduceRight<T>(array: T[], f: (memo: T, value: T, i: number) => T, initial?: T, start?: number, count?: number): T {
         if (array) {
-            let pos = array.length - 1;
-            if (pos >= 0) {
-                let result: T | U;
+            const size = array.length;
+            if (size > 0) {
+                let pos = start === undefined || start > size - 1 ? size - 1 : start;
+                const end = count === undefined || pos - count < 0 ? 0 : pos - count;
+                let result: T;
                 if (arguments.length <= 2) {
                     result = array[pos];
                     pos--;
@@ -371,11 +546,11 @@ namespace ts {
                 else {
                     result = initial;
                 }
-                while (pos >= 0) {
-                    result = f(<U>result, array[pos]);
+                while (pos >= end) {
+                    result = f(result, array[pos], pos);
                     pos--;
                 }
-                return <U>result;
+                return result;
             }
         }
         return initial;
@@ -539,6 +714,15 @@ namespace ts {
         return result;
     }
 
+    export function isEmpty<T>(map: Map<T>) {
+        for (const id in map) {
+            if (hasProperty(map, id)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
     export function cloneMap<T>(map: Map<T>) {
         const clone = createMap<T>();
         copyProperties(map, clone);
@@ -566,6 +750,36 @@ namespace ts {
         return result;
     }
 
+    /**
+     * Adds the value to an array of values associated with the key, and returns the array.
+     * Creates the array if it does not already exist.
+     */
+    export function multiMapAdd<V>(map: Map<V[]>, key: string, value: V): V[] {
+        const values = map[key];
+        if (values) {
+            values.push(value);
+            return values;
+        }
+        else {
+            return map[key] = [value];
+        }
+    }
+
+    /**
+     * Removes a value from an array of values associated with the key.
+     * Does not preserve the order of those values.
+     * Does nothing if `key` is not in `map`, or `value` is not in `map[key]`.
+     */
+    export function multiMapRemove<V>(map: Map<V[]>, key: string, value: V): void {
+        const values = map[key];
+        if (values) {
+            unorderedRemoveItem(values, value);
+            if (!values.length) {
+                delete map[key];
+            }
+        }
+    }
+
     /**
      * Tests whether a value is an array.
      */
@@ -1453,11 +1667,16 @@ namespace ts {
     }
 
     function Node(this: Node, kind: SyntaxKind, pos: number, end: number) {
+        this.id = 0;
         this.kind = kind;
         this.pos = pos;
         this.end = end;
         this.flags = NodeFlags.None;
+        this.modifierFlagsCache = ModifierFlags.None;
+        this.transformFlags = TransformFlags.None;
         this.parent = undefined;
+        this.original = undefined;
+        this.transformId = 0;
     }
 
     export let objectAllocator: ObjectAllocator = {
@@ -1478,10 +1697,13 @@ namespace ts {
     }
 
     export namespace Debug {
-        const currentAssertionLevel = AssertionLevel.None;
+        declare var process: any;
+        declare var require: any;
+
+        let currentAssertionLevel: AssertionLevel;
 
         export function shouldAssert(level: AssertionLevel): boolean {
-            return currentAssertionLevel >= level;
+            return getCurrentAssertionLevel() >= level;
         }
 
         export function assert(expression: boolean, message?: string, verboseDebugInfo?: () => string): void {
@@ -1498,22 +1720,70 @@ namespace ts {
         export function fail(message?: string): void {
             Debug.assert(/*expression*/ false, message);
         }
+
+        function getCurrentAssertionLevel() {
+            if (currentAssertionLevel !== undefined) {
+                return currentAssertionLevel;
+            }
+
+            if (sys === undefined) {
+                return AssertionLevel.None;
+            }
+
+            const developmentMode = /^development$/i.test(getEnvironmentVariable("NODE_ENV"));
+            currentAssertionLevel = developmentMode
+                ? AssertionLevel.Normal
+                : AssertionLevel.None;
+
+            return currentAssertionLevel;
+        }
     }
 
-    export function copyListRemovingItem<T>(item: T, list: T[]) {
-        const copiedList: T[] = [];
-        for (const e of list) {
-            if (e !== item) {
-                copiedList.push(e);
+    export function getEnvironmentVariable(name: string, host?: CompilerHost) {
+        if (host && host.getEnvironmentVariable) {
+            return host.getEnvironmentVariable(name);
+        }
+
+        if (sys && sys.getEnvironmentVariable) {
+            return sys.getEnvironmentVariable(name);
+        }
+
+        return "";
+    }
+
+    /** Remove an item from an array, moving everything to its right one space left. */
+    export function orderedRemoveItemAt<T>(array: T[], index: number): void {
+        // This seems to be faster than either `array.splice(i, 1)` or `array.copyWithin(i, i+ 1)`.
+        for (let i = index; i < array.length - 1; i++) {
+            array[i] = array[i + 1];
+        }
+        array.pop();
+    }
+
+    export function unorderedRemoveItemAt<T>(array: T[], index: number): void {
+        // Fill in the "hole" left at `index`.
+        array[index] = array[array.length - 1];
+        array.pop();
+    }
+
+    /** Remove the *first* occurrence of `item` from the array. */
+    export function unorderedRemoveItem<T>(array: T[], item: T): void {
+        unorderedRemoveFirstItemWhere(array, element => element === item);
+    }
+
+    /** Remove the *first* element satisfying `predicate`. */
+    function unorderedRemoveFirstItemWhere<T>(array: T[], predicate: (element: T) => boolean): void {
+        for (let i = 0; i < array.length; i++) {
+            if (predicate(array[i])) {
+                unorderedRemoveItemAt(array, i);
+                break;
             }
         }
-        return copiedList;
     }
 
-    export function createGetCanonicalFileName(useCaseSensitivefileNames: boolean): (fileName: string) => string {
-        return useCaseSensitivefileNames
+    export function createGetCanonicalFileName(useCaseSensitiveFileNames: boolean): (fileName: string) => string {
+        return useCaseSensitiveFileNames
             ? ((fileName) => fileName)
             : ((fileName) => fileName.toLowerCase());
     }
-
 }

src/compiler/declarationEmitter.ts

@@ -374,7 +374,7 @@ namespace ts {
                 const jsDocComments = getJsDocCommentsFromText(declaration, currentText);
                 emitNewLineBeforeLeadingComments(currentLineMap, writer, declaration, jsDocComments);
                 // jsDoc comments are emitted at /*leading comment1 */space/*leading comment*/space
-                emitComments(currentText, currentLineMap, writer, jsDocComments, /*trailingSeparator*/ true, newLine, writeCommentRange);
+                emitComments(currentText, currentLineMap, writer, jsDocComments, /*leadingSeparator*/ false, /*trailingSeparator*/ true, newLine, writeCommentRange);
             }
         }
 
@@ -655,12 +655,13 @@ namespace ts {
         function emitModuleElementDeclarationFlags(node: Node) {
             // If the node is parented in the current source file we need to emit export declare or just export
             if (node.parent.kind === SyntaxKind.SourceFile) {
+                const modifiers = getModifierFlags(node);
                 // If the node is exported
-                if (node.flags & NodeFlags.Export) {
+                if (modifiers & ModifierFlags.Export) {
                     write("export ");
                 }
 
-                if (node.flags & NodeFlags.Default) {
+                if (modifiers & ModifierFlags.Default) {
                     write("default ");
                 }
                 else if (node.kind !== SyntaxKind.InterfaceDeclaration && !noDeclare) {
@@ -669,21 +670,21 @@ namespace ts {
             }
         }
 
-        function emitClassMemberDeclarationFlags(flags: NodeFlags) {
-            if (flags & NodeFlags.Private) {
+        function emitClassMemberDeclarationFlags(flags: ModifierFlags) {
+            if (flags & ModifierFlags.Private) {
                 write("private ");
             }
-            else if (flags & NodeFlags.Protected) {
+            else if (flags & ModifierFlags.Protected) {
                 write("protected ");
             }
 
-            if (flags & NodeFlags.Static) {
+            if (flags & ModifierFlags.Static) {
                 write("static ");
             }
-            if (flags & NodeFlags.Readonly) {
+            if (flags & ModifierFlags.Readonly) {
                 write("readonly ");
             }
-            if (flags & NodeFlags.Abstract) {
+            if (flags & ModifierFlags.Abstract) {
                 write("abstract ");
             }
         }
@@ -692,7 +693,7 @@ namespace ts {
             // note usage of writer. methods instead of aliases created, just to make sure we are using
             // correct writer especially to handle asynchronous alias writing
             emitJsDocComments(node);
-            if (node.flags & NodeFlags.Export) {
+            if (hasModifier(node, ModifierFlags.Export)) {
                 write("export ");
             }
             write("import ");
@@ -731,7 +732,7 @@ namespace ts {
 
         function writeImportDeclaration(node: ImportDeclaration) {
             emitJsDocComments(node);
-            if (node.flags & NodeFlags.Export) {
+            if (hasModifier(node, ModifierFlags.Export)) {
                 write("export ");
             }
             write("import ");
@@ -926,7 +927,7 @@ namespace ts {
         }
 
         function isPrivateMethodTypeParameter(node: TypeParameterDeclaration) {
-            return node.parent.kind === SyntaxKind.MethodDeclaration && (node.parent.flags & NodeFlags.Private);
+            return node.parent.kind === SyntaxKind.MethodDeclaration && hasModifier(node.parent, ModifierFlags.Private);
         }
 
         function emitTypeParameters(typeParameters: TypeParameterDeclaration[]) {
@@ -976,7 +977,7 @@ namespace ts {
 
                         case SyntaxKind.MethodDeclaration:
                         case SyntaxKind.MethodSignature:
-                            if (node.parent.flags & NodeFlags.Static) {
+                            if (hasModifier(node.parent, ModifierFlags.Static)) {
                                 diagnosticMessage = Diagnostics.Type_parameter_0_of_public_static_method_from_exported_class_has_or_is_using_private_name_1;
                             }
                             else if (node.parent.parent.kind === SyntaxKind.ClassDeclaration) {
@@ -1055,7 +1056,7 @@ namespace ts {
             function emitParameterProperties(constructorDeclaration: ConstructorDeclaration) {
                 if (constructorDeclaration) {
                     forEach(constructorDeclaration.parameters, param => {
-                        if (param.flags & NodeFlags.ParameterPropertyModifier) {
+                        if (hasModifier(param, ModifierFlags.ParameterPropertyModifier)) {
                             emitPropertyDeclaration(param);
                         }
                     });
@@ -1064,7 +1065,7 @@ namespace ts {
 
             emitJsDocComments(node);
             emitModuleElementDeclarationFlags(node);
-            if (node.flags & NodeFlags.Abstract) {
+            if (hasModifier(node, ModifierFlags.Abstract)) {
                 write("abstract ");
             }
 
@@ -1114,7 +1115,7 @@ namespace ts {
             }
 
             emitJsDocComments(node);
-            emitClassMemberDeclarationFlags(node.flags);
+            emitClassMemberDeclarationFlags(getModifierFlags(node));
             emitVariableDeclaration(<VariableDeclaration>node);
             write(";");
             writeLine();
@@ -1141,7 +1142,7 @@ namespace ts {
                     if ((node.kind === SyntaxKind.PropertyDeclaration || node.kind === SyntaxKind.PropertySignature) && node.parent.kind === SyntaxKind.TypeLiteral) {
                         emitTypeOfVariableDeclarationFromTypeLiteral(node);
                     }
-                    else if (!(node.flags & NodeFlags.Private)) {
+                    else if (!hasModifier(node, ModifierFlags.Private)) {
                         writeTypeOfDeclaration(node, node.type, getVariableDeclarationTypeVisibilityError);
                     }
                 }
@@ -1158,7 +1159,7 @@ namespace ts {
                 // This check is to ensure we don't report error on constructor parameter property as that error would be reported during parameter emit
                 else if (node.kind === SyntaxKind.PropertyDeclaration || node.kind === SyntaxKind.PropertySignature) {
                     // TODO(jfreeman): Deal with computed properties in error reporting.
-                    if (node.flags & NodeFlags.Static) {
+                    if (hasModifier(node, ModifierFlags.Static)) {
                         return symbolAccessibilityResult.errorModuleName ?
                             symbolAccessibilityResult.accessibility === SymbolAccessibility.CannotBeNamed ?
                                 Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
@@ -1269,9 +1270,9 @@ namespace ts {
             if (node === accessors.firstAccessor) {
                 emitJsDocComments(accessors.getAccessor);
                 emitJsDocComments(accessors.setAccessor);
-                emitClassMemberDeclarationFlags(node.flags | (accessors.setAccessor ? 0 : NodeFlags.Readonly));
+                emitClassMemberDeclarationFlags(getModifierFlags(node) | (accessors.setAccessor ? 0 : ModifierFlags.Readonly));
                 writeTextOfNode(currentText, node.name);
-                if (!(node.flags & NodeFlags.Private)) {
+                if (!hasModifier(node, ModifierFlags.Private)) {
                     accessorWithTypeAnnotation = node;
                     let type = getTypeAnnotationFromAccessor(node);
                     if (!type) {
@@ -1302,7 +1303,7 @@ namespace ts {
                 let diagnosticMessage: DiagnosticMessage;
                 if (accessorWithTypeAnnotation.kind === SyntaxKind.SetAccessor) {
                     // Setters have to have type named and cannot infer it so, the type should always be named
-                    if (accessorWithTypeAnnotation.parent.flags & NodeFlags.Static) {
+                    if (hasModifier(accessorWithTypeAnnotation.parent, ModifierFlags.Static)) {
                         diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
                             Diagnostics.Parameter_0_of_public_static_property_setter_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
                             Diagnostics.Parameter_0_of_public_static_property_setter_from_exported_class_has_or_is_using_private_name_1;
@@ -1320,7 +1321,7 @@ namespace ts {
                     };
                 }
                 else {
-                    if (accessorWithTypeAnnotation.flags & NodeFlags.Static) {
+                    if (hasModifier(accessorWithTypeAnnotation, ModifierFlags.Static)) {
                         diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
                             symbolAccessibilityResult.accessibility === SymbolAccessibility.CannotBeNamed ?
                                 Diagnostics.Return_type_of_public_static_property_getter_from_exported_class_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named :
@@ -1356,7 +1357,7 @@ namespace ts {
                     emitModuleElementDeclarationFlags(node);
                 }
                 else if (node.kind === SyntaxKind.MethodDeclaration || node.kind === SyntaxKind.Constructor) {
-                    emitClassMemberDeclarationFlags(node.flags);
+                    emitClassMemberDeclarationFlags(getModifierFlags(node));
                 }
                 if (node.kind === SyntaxKind.FunctionDeclaration) {
                     write("function ");
@@ -1387,7 +1388,7 @@ namespace ts {
 
             if (node.kind === SyntaxKind.IndexSignature) {
                 // Index signature can have readonly modifier
-                emitClassMemberDeclarationFlags(node.flags);
+                emitClassMemberDeclarationFlags(getModifierFlags(node));
                 write("[");
             }
             else {
@@ -1428,7 +1429,7 @@ namespace ts {
                     emitType(node.type);
                 }
             }
-            else if (node.kind !== SyntaxKind.Constructor && !(node.flags & NodeFlags.Private)) {
+            else if (node.kind !== SyntaxKind.Constructor && !hasModifier(node, ModifierFlags.Private)) {
                 writeReturnTypeAtSignature(node, getReturnTypeVisibilityError);
             }
 
@@ -1468,7 +1469,7 @@ namespace ts {
 
                     case SyntaxKind.MethodDeclaration:
                     case SyntaxKind.MethodSignature:
-                        if (node.flags & NodeFlags.Static) {
+                        if (hasModifier(node, ModifierFlags.Static)) {
                             diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
                                 symbolAccessibilityResult.accessibility === SymbolAccessibility.CannotBeNamed ?
                                     Diagnostics.Return_type_of_public_static_method_from_exported_class_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named :
@@ -1534,7 +1535,7 @@ namespace ts {
                 node.parent.parent.kind === SyntaxKind.TypeLiteral) {
                 emitTypeOfVariableDeclarationFromTypeLiteral(node);
             }
-            else if (!(node.parent.flags & NodeFlags.Private)) {
+            else if (!hasModifier(node.parent, ModifierFlags.Private)) {
                 writeTypeOfDeclaration(node, node.type, getParameterDeclarationTypeVisibilityError);
             }
 
@@ -1570,7 +1571,7 @@ namespace ts {
 
                     case SyntaxKind.MethodDeclaration:
                     case SyntaxKind.MethodSignature:
-                        if (node.parent.flags & NodeFlags.Static) {
+                        if (hasModifier(node.parent, ModifierFlags.Static)) {
                             return symbolAccessibilityResult.errorModuleName ?
                                 symbolAccessibilityResult.accessibility === SymbolAccessibility.CannotBeNamed ?
                                     Diagnostics.Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :

src/compiler/diagnosticMessages.json

@@ -827,10 +827,6 @@
         "category": "Error",
         "code": 1308
     },
-    "Async functions are only available when targeting ECMAScript 2015 or higher.": {
-        "category": "Error",
-        "code": 1311
-    },
     "'=' can only be used in an object literal property inside a destructuring assignment.": {
         "category": "Error",
         "code": 1312
@@ -1703,7 +1699,7 @@
         "category": "Error",
         "code": 2521
     },
-    "The 'arguments' object cannot be referenced in an async arrow function. Consider using a standard async function expression.": {
+    "The 'arguments' object cannot be referenced in an async function or method in ES3 and ES5. Consider using a standard function or method.": {
         "category": "Error",
         "code": 2522
     },
@@ -2840,6 +2836,10 @@
         "category": "Error",
         "code": 6138
     },
+    "Import emit helpers from 'tslib'.": {
+        "category": "Message",
+        "code": 6139
+    },
     "Variable '{0}' implicitly has an '{1}' type.": {
         "category": "Error",
         "code": 7005

src/compiler/parser.ts

@@ -1,5 +1,6 @@
 /// <reference path="utilities.ts"/>
 /// <reference path="scanner.ts"/>
+/// <reference path="factory.ts"/>
 
 namespace ts {
     let NodeConstructor: new (kind: SyntaxKind, pos: number, end: number) => Node;
@@ -417,6 +418,8 @@ namespace ts {
             case SyntaxKind.JSDocPropertyTag:
                 return visitNode(cbNode, (<JSDocPropertyTag>node).typeExpression) ||
                     visitNode(cbNode, (<JSDocPropertyTag>node).name);
+            case SyntaxKind.PartiallyEmittedExpression:
+                return visitNode(cbNode, (<PartiallyEmittedExpression>node).expression);
             case SyntaxKind.JSDocLiteralType:
                     return visitNode(cbNode, (<JSDocLiteralType>node).literal);
         }
@@ -1053,6 +1056,16 @@ namespace ts {
                     new TokenConstructor(kind, pos, pos);
         }
 
+        function createNodeArray<T extends Node>(elements?: T[], pos?: number): NodeArray<T> {
+            const array = <NodeArray<T>>(elements || []);
+            if (!(pos >= 0)) {
+                pos = getNodePos();
+            }
+            array.pos = pos;
+            array.end = pos;
+            return array;
+        }
+
         function finishNode<T extends Node>(node: T, end?: number): T {
             node.end = end === undefined ? scanner.getStartPos() : end;
 
@@ -1440,8 +1453,7 @@ namespace ts {
         function parseList<T extends Node>(kind: ParsingContext, parseElement: () => T): NodeArray<T> {
             const saveParsingContext = parsingContext;
             parsingContext |= 1 << kind;
-            const result = <NodeArray<T>>[];
-            result.pos = getNodePos();
+            const result = createNodeArray<T>();
 
             while (!isListTerminator(kind)) {
                 if (isListElement(kind, /*inErrorRecovery*/ false)) {
@@ -1788,8 +1800,7 @@ namespace ts {
         function parseDelimitedList<T extends Node>(kind: ParsingContext, parseElement: () => T, considerSemicolonAsDelimiter?: boolean): NodeArray<T> {
             const saveParsingContext = parsingContext;
             parsingContext |= 1 << kind;
-            const result = <NodeArray<T>>[];
-            result.pos = getNodePos();
+            const result = createNodeArray<T>();
 
             let commaStart = -1; // Meaning the previous token was not a comma
             while (true) {
@@ -1844,12 +1855,8 @@ namespace ts {
             return result;
         }
 
-        function createMissingList<T>(): NodeArray<T> {
-            const pos = getNodePos();
-            const result = <NodeArray<T>>[];
-            result.pos = pos;
-            result.end = pos;
-            return result;
+        function createMissingList<T extends Node>(): NodeArray<T> {
+            return createNodeArray<T>();
         }
 
         function parseBracketedList<T extends Node>(kind: ParsingContext, parseElement: () => T, open: SyntaxKind, close: SyntaxKind): NodeArray<T> {
@@ -1914,8 +1921,7 @@ namespace ts {
             template.head = parseTemplateLiteralFragment();
             Debug.assert(template.head.kind === SyntaxKind.TemplateHead, "Template head has wrong token kind");
 
-            const templateSpans = <NodeArray<TemplateSpan>>[];
-            templateSpans.pos = getNodePos();
+            const templateSpans = createNodeArray<TemplateSpan>();
 
             do {
                 templateSpans.push(parseTemplateSpan());
@@ -2064,13 +2070,6 @@ namespace ts {
             return token() === SyntaxKind.DotDotDotToken || isIdentifierOrPattern() || isModifierKind(token()) || token() === SyntaxKind.AtToken || token() === SyntaxKind.ThisKeyword;
         }
 
-        function setModifiers(node: Node, modifiers: ModifiersArray) {
-            if (modifiers) {
-                node.flags |= modifiers.flags;
-                node.modifiers = modifiers;
-            }
-        }
-
         function parseParameter(): ParameterDeclaration {
             const node = <ParameterDeclaration>createNode(SyntaxKind.Parameter);
             if (token() === SyntaxKind.ThisKeyword) {
@@ -2080,13 +2079,13 @@ namespace ts {
             }
 
             node.decorators = parseDecorators();
-            setModifiers(node, parseModifiers());
+            node.modifiers = parseModifiers();
             node.dotDotDotToken = parseOptionalToken(SyntaxKind.DotDotDotToken);
 
             // FormalParameter [Yield,Await]:
             //      BindingElement[?Yield,?Await]
             node.name = parseIdentifierOrPattern();
-            if (getFullWidth(node.name) === 0 && node.flags === 0 && isModifierKind(token())) {
+            if (getFullWidth(node.name) === 0 && !hasModifiers(node) && isModifierKind(token())) {
                 // in cases like
                 // 'use strict'
                 // function foo(static)
@@ -2267,23 +2266,23 @@ namespace ts {
             return token() === SyntaxKind.ColonToken || token() === SyntaxKind.CommaToken || token() === SyntaxKind.CloseBracketToken;
         }
 
-        function parseIndexSignatureDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): IndexSignatureDeclaration {
+        function parseIndexSignatureDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): IndexSignatureDeclaration {
             const node = <IndexSignatureDeclaration>createNode(SyntaxKind.IndexSignature, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             node.parameters = parseBracketedList(ParsingContext.Parameters, parseParameter, SyntaxKind.OpenBracketToken, SyntaxKind.CloseBracketToken);
             node.type = parseTypeAnnotation();
             parseTypeMemberSemicolon();
             return finishNode(node);
         }
 
-        function parsePropertyOrMethodSignature(fullStart: number, modifiers: ModifiersArray): PropertySignature | MethodSignature {
+        function parsePropertyOrMethodSignature(fullStart: number, modifiers: NodeArray<Modifier>): PropertySignature | MethodSignature {
             const name = parsePropertyName();
             const questionToken = parseOptionalToken(SyntaxKind.QuestionToken);
 
             if (token() === SyntaxKind.OpenParenToken || token() === SyntaxKind.LessThanToken) {
                 const method = <MethodSignature>createNode(SyntaxKind.MethodSignature, fullStart);
-                setModifiers(method, modifiers);
+                method.modifiers = modifiers;
                 method.name = name;
                 method.questionToken = questionToken;
 
@@ -2295,7 +2294,7 @@ namespace ts {
             }
             else {
                 const property = <PropertySignature>createNode(SyntaxKind.PropertySignature, fullStart);
-                setModifiers(property, modifiers);
+                property.modifiers = modifiers;
                 property.name = name;
                 property.questionToken = questionToken;
                 property.type = parseTypeAnnotation();
@@ -2519,8 +2518,7 @@ namespace ts {
         function parseUnionOrIntersectionType(kind: SyntaxKind, parseConstituentType: () => TypeNode, operator: SyntaxKind): TypeNode {
             let type = parseConstituentType();
             if (token() === operator) {
-                const types = <NodeArray<TypeNode>>[type];
-                types.pos = type.pos;
+                const types = createNodeArray<TypeNode>([type], type.pos);
                 while (parseOptional(operator)) {
                     types.push(parseConstituentType());
                 }
@@ -2874,13 +2872,13 @@ namespace ts {
             }
         }
 
-        function parseSimpleArrowFunctionExpression(identifier: Identifier, asyncModifier?: ModifiersArray): ArrowFunction {
+        function parseSimpleArrowFunctionExpression(identifier: Identifier, asyncModifier?: NodeArray<Modifier>): ArrowFunction {
             Debug.assert(token() === SyntaxKind.EqualsGreaterThanToken, "parseSimpleArrowFunctionExpression should only have been called if we had a =>");
 
             let node: ArrowFunction;
             if (asyncModifier) {
                 node = <ArrowFunction>createNode(SyntaxKind.ArrowFunction, asyncModifier.pos);
-                setModifiers(node, asyncModifier);
+                node.modifiers = asyncModifier;
             }
             else {
                 node = <ArrowFunction>createNode(SyntaxKind.ArrowFunction, identifier.pos);
@@ -2890,8 +2888,7 @@ namespace ts {
             parameter.name = identifier;
             finishNode(parameter);
 
-            node.parameters = <NodeArray<ParameterDeclaration>>[parameter];
-            node.parameters.pos = parameter.pos;
+            node.parameters = createNodeArray<ParameterDeclaration>([parameter], parameter.pos);
             node.parameters.end = parameter.end;
 
             node.equalsGreaterThanToken = parseExpectedToken(SyntaxKind.EqualsGreaterThanToken, /*reportAtCurrentPosition*/ false, Diagnostics._0_expected, "=>");
@@ -2920,7 +2917,7 @@ namespace ts {
                 return undefined;
             }
 
-            const isAsync = !!(arrowFunction.flags & NodeFlags.Async);
+            const isAsync = !!(getModifierFlags(arrowFunction) & ModifierFlags.Async);
 
             // If we have an arrow, then try to parse the body. Even if not, try to parse if we
             // have an opening brace, just in case we're in an error state.
@@ -3099,8 +3096,8 @@ namespace ts {
 
         function parseParenthesizedArrowFunctionExpressionHead(allowAmbiguity: boolean): ArrowFunction {
             const node = <ArrowFunction>createNode(SyntaxKind.ArrowFunction);
-            setModifiers(node, parseModifiersForArrowFunction());
-            const isAsync = !!(node.flags & NodeFlags.Async);
+            node.modifiers = parseModifiersForArrowFunction();
+            const isAsync = !!(getModifierFlags(node) & ModifierFlags.Async);
 
             // Arrow functions are never generators.
             //
@@ -3729,8 +3726,7 @@ namespace ts {
         }
 
         function parseJsxChildren(openingTagName: LeftHandSideExpression): NodeArray<JsxChild> {
-            const result = <NodeArray<JsxChild>>[];
-            result.pos = scanner.getStartPos();
+            const result = createNodeArray<JsxChild>();
             const saveParsingContext = parsingContext;
             parsingContext |= 1 << ParsingContext.JsxChildren;
 
@@ -4112,7 +4108,7 @@ namespace ts {
             return finishNode(node);
         }
 
-        function tryParseAccessorDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): AccessorDeclaration {
+        function tryParseAccessorDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): AccessorDeclaration {
             if (parseContextualModifier(SyntaxKind.GetKeyword)) {
                 return addJSDocComment(parseAccessorDeclaration(SyntaxKind.GetAccessor, fullStart, decorators, modifiers));
             }
@@ -4197,12 +4193,12 @@ namespace ts {
             }
 
             const node = <FunctionExpression>createNode(SyntaxKind.FunctionExpression);
-            setModifiers(node, parseModifiers());
+            node.modifiers = parseModifiers();
             parseExpected(SyntaxKind.FunctionKeyword);
             node.asteriskToken = parseOptionalToken(SyntaxKind.AsteriskToken);
 
             const isGenerator = !!node.asteriskToken;
-            const isAsync = !!(node.flags & NodeFlags.Async);
+            const isAsync = !!(getModifierFlags(node) & ModifierFlags.Async);
             node.name =
                 isGenerator && isAsync ? doInYieldAndAwaitContext(parseOptionalIdentifier) :
                     isGenerator ? doInYieldContext(parseOptionalIdentifier) :
@@ -4239,6 +4235,10 @@ namespace ts {
         function parseBlock(ignoreMissingOpenBrace: boolean, diagnosticMessage?: DiagnosticMessage): Block {
             const node = <Block>createNode(SyntaxKind.Block);
             if (parseExpected(SyntaxKind.OpenBraceToken, diagnosticMessage) || ignoreMissingOpenBrace) {
+                if (scanner.hasPrecedingLineBreak()) {
+                    node.multiLine = true;
+                }
+
                 node.statements = parseList(ParsingContext.BlockStatements, parseStatement);
                 parseExpected(SyntaxKind.CloseBraceToken);
             }
@@ -4789,7 +4789,7 @@ namespace ts {
                         const node = <Statement>createMissingNode(SyntaxKind.MissingDeclaration, /*reportAtCurrentPosition*/ true, Diagnostics.Declaration_expected);
                         node.pos = fullStart;
                         node.decorators = decorators;
-                        setModifiers(node, modifiers);
+                        node.modifiers = modifiers;
                         return finishNode(node);
                     }
             }
@@ -4924,57 +4924,57 @@ namespace ts {
             return nextTokenIsIdentifier() && nextToken() === SyntaxKind.CloseParenToken;
         }
 
-        function parseVariableStatement(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): VariableStatement {
+        function parseVariableStatement(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): VariableStatement {
             const node = <VariableStatement>createNode(SyntaxKind.VariableStatement, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             node.declarationList = parseVariableDeclarationList(/*inForStatementInitializer*/ false);
             parseSemicolon();
             return addJSDocComment(finishNode(node));
         }
 
-        function parseFunctionDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): FunctionDeclaration {
+        function parseFunctionDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): FunctionDeclaration {
             const node = <FunctionDeclaration>createNode(SyntaxKind.FunctionDeclaration, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             parseExpected(SyntaxKind.FunctionKeyword);
             node.asteriskToken = parseOptionalToken(SyntaxKind.AsteriskToken);
-            node.name = node.flags & NodeFlags.Default ? parseOptionalIdentifier() : parseIdentifier();
+            node.name = hasModifier(node, ModifierFlags.Default) ? parseOptionalIdentifier() : parseIdentifier();
             const isGenerator = !!node.asteriskToken;
-            const isAsync = !!(node.flags & NodeFlags.Async);
+            const isAsync = hasModifier(node, ModifierFlags.Async);
             fillSignature(SyntaxKind.ColonToken, /*yieldContext*/ isGenerator, /*awaitContext*/ isAsync, /*requireCompleteParameterList*/ false, node);
             node.body = parseFunctionBlockOrSemicolon(isGenerator, isAsync, Diagnostics.or_expected);
             return addJSDocComment(finishNode(node));
         }
 
-        function parseConstructorDeclaration(pos: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ConstructorDeclaration {
+        function parseConstructorDeclaration(pos: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ConstructorDeclaration {
             const node = <ConstructorDeclaration>createNode(SyntaxKind.Constructor, pos);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             parseExpected(SyntaxKind.ConstructorKeyword);
             fillSignature(SyntaxKind.ColonToken, /*yieldContext*/ false, /*awaitContext*/ false, /*requireCompleteParameterList*/ false, node);
             node.body = parseFunctionBlockOrSemicolon(/*isGenerator*/ false, /*isAsync*/ false, Diagnostics.or_expected);
             return addJSDocComment(finishNode(node));
         }
 
-        function parseMethodDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray, asteriskToken: Node, name: PropertyName, questionToken: Node, diagnosticMessage?: DiagnosticMessage): MethodDeclaration {
+        function parseMethodDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>, asteriskToken: Node, name: PropertyName, questionToken: Node, diagnosticMessage?: DiagnosticMessage): MethodDeclaration {
             const method = <MethodDeclaration>createNode(SyntaxKind.MethodDeclaration, fullStart);
             method.decorators = decorators;
-            setModifiers(method, modifiers);
+            method.modifiers = modifiers;
             method.asteriskToken = asteriskToken;
             method.name = name;
             method.questionToken = questionToken;
             const isGenerator = !!asteriskToken;
-            const isAsync = !!(method.flags & NodeFlags.Async);
+            const isAsync = hasModifier(method, ModifierFlags.Async);
             fillSignature(SyntaxKind.ColonToken, /*yieldContext*/ isGenerator, /*awaitContext*/ isAsync, /*requireCompleteParameterList*/ false, method);
             method.body = parseFunctionBlockOrSemicolon(isGenerator, isAsync, diagnosticMessage);
             return addJSDocComment(finishNode(method));
         }
 
-        function parsePropertyDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray, name: PropertyName, questionToken: Node): ClassElement {
+        function parsePropertyDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>, name: PropertyName, questionToken: Node): ClassElement {
             const property = <PropertyDeclaration>createNode(SyntaxKind.PropertyDeclaration, fullStart);
             property.decorators = decorators;
-            setModifiers(property, modifiers);
+            property.modifiers = modifiers;
             property.name = name;
             property.questionToken = questionToken;
             property.type = parseTypeAnnotation();
@@ -4988,7 +4988,7 @@ namespace ts {
             //        AccessibilityModifier_opt  static_opt  PropertyName   TypeAnnotation_opt   Initializer_opt[In, ?Yield];
             //
             // The checker may still error in the static case to explicitly disallow the yield expression.
-            property.initializer = modifiers && modifiers.flags & NodeFlags.Static
+            property.initializer = hasModifier(property, ModifierFlags.Static)
                 ? allowInAnd(parseNonParameterInitializer)
                 : doOutsideOfContext(NodeFlags.YieldContext | NodeFlags.DisallowInContext, parseNonParameterInitializer);
 
@@ -4996,7 +4996,7 @@ namespace ts {
             return finishNode(property);
         }
 
-        function parsePropertyOrMethodDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ClassElement {
+        function parsePropertyOrMethodDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ClassElement {
             const asteriskToken = parseOptionalToken(SyntaxKind.AsteriskToken);
             const name = parsePropertyName();
 
@@ -5015,10 +5015,10 @@ namespace ts {
             return parseInitializer(/*inParameter*/ false);
         }
 
-        function parseAccessorDeclaration(kind: SyntaxKind, fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): AccessorDeclaration {
+        function parseAccessorDeclaration(kind: SyntaxKind, fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): AccessorDeclaration {
             const node = <AccessorDeclaration>createNode(kind, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             node.name = parsePropertyName();
             fillSignature(SyntaxKind.ColonToken, /*yieldContext*/ false, /*awaitContext*/ false, /*requireCompleteParameterList*/ false, node);
             node.body = parseFunctionBlockOrSemicolon(/*isGenerator*/ false, /*isAsync*/ false);
@@ -5114,14 +5114,15 @@ namespace ts {
                     break;
                 }
 
-                if (!decorators) {
-                    decorators = <NodeArray<Decorator>>[];
-                    decorators.pos = decoratorStart;
-                }
-
                 const decorator = <Decorator>createNode(SyntaxKind.Decorator, decoratorStart);
                 decorator.expression = doInDecoratorContext(parseLeftHandSideExpressionOrHigher);
-                decorators.push(finishNode(decorator));
+                finishNode(decorator);
+                if (!decorators) {
+                    decorators = createNodeArray<Decorator>([decorator], decoratorStart);
+                }
+                else {
+                    decorators.push(decorator);
+                }
             }
             if (decorators) {
                 decorators.end = getNodeEnd();
@@ -5136,9 +5137,8 @@ namespace ts {
          *
          * In such situations, 'permitInvalidConstAsModifier' should be set to true.
          */
-        function parseModifiers(permitInvalidConstAsModifier?: boolean): ModifiersArray {
-            let flags: NodeFlags = 0;
-            let modifiers: ModifiersArray;
+        function parseModifiers(permitInvalidConstAsModifier?: boolean): NodeArray<Modifier> {
+            let modifiers: NodeArray<Modifier>;
             while (true) {
                 const modifierStart = scanner.getStartPos();
                 const modifierKind = token();
@@ -5156,33 +5156,28 @@ namespace ts {
                     }
                 }
 
+                const modifier = finishNode(<Modifier>createNode(modifierKind, modifierStart));
                 if (!modifiers) {
-                    modifiers = <ModifiersArray>[];
-                    modifiers.pos = modifierStart;
+                    modifiers = createNodeArray<Modifier>([modifier], modifierStart);
+                }
+                else {
+                    modifiers.push(modifier);
                 }
-
-                flags |= modifierToFlag(modifierKind);
-                modifiers.push(finishNode(<Modifier>createNode(modifierKind, modifierStart)));
             }
             if (modifiers) {
-                modifiers.flags = flags;
                 modifiers.end = scanner.getStartPos();
             }
             return modifiers;
         }
 
-        function parseModifiersForArrowFunction(): ModifiersArray {
-            let flags = 0;
-            let modifiers: ModifiersArray;
+        function parseModifiersForArrowFunction(): NodeArray<Modifier> {
+            let modifiers: NodeArray<Modifier>;
             if (token() === SyntaxKind.AsyncKeyword) {
                 const modifierStart = scanner.getStartPos();
                 const modifierKind = token();
                 nextToken();
-                modifiers = <ModifiersArray>[];
-                modifiers.pos = modifierStart;
-                flags |= modifierToFlag(modifierKind);
-                modifiers.push(finishNode(<Modifier>createNode(modifierKind, modifierStart)));
-                modifiers.flags = flags;
+                const modifier = finishNode(<Modifier>createNode(modifierKind, modifierStart));
+                modifiers = createNodeArray<Modifier>([modifier], modifierStart);
                 modifiers.end = scanner.getStartPos();
             }
 
@@ -5242,14 +5237,14 @@ namespace ts {
                 SyntaxKind.ClassExpression);
         }
 
-        function parseClassDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ClassDeclaration {
+        function parseClassDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ClassDeclaration {
             return <ClassDeclaration>parseClassDeclarationOrExpression(fullStart, decorators, modifiers, SyntaxKind.ClassDeclaration);
         }
 
-        function parseClassDeclarationOrExpression(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray, kind: SyntaxKind): ClassLikeDeclaration {
+        function parseClassDeclarationOrExpression(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>, kind: SyntaxKind): ClassLikeDeclaration {
             const node = <ClassLikeDeclaration>createNode(kind, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             parseExpected(SyntaxKind.ClassKeyword);
             node.name = parseNameOfClassDeclarationOrExpression();
             node.typeParameters = parseTypeParameters();
@@ -5324,10 +5319,10 @@ namespace ts {
             return parseList(ParsingContext.ClassMembers, parseClassElement);
         }
 
-        function parseInterfaceDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): InterfaceDeclaration {
+        function parseInterfaceDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): InterfaceDeclaration {
             const node = <InterfaceDeclaration>createNode(SyntaxKind.InterfaceDeclaration, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             parseExpected(SyntaxKind.InterfaceKeyword);
             node.name = parseIdentifier();
             node.typeParameters = parseTypeParameters();
@@ -5336,10 +5331,10 @@ namespace ts {
             return finishNode(node);
         }
 
-        function parseTypeAliasDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): TypeAliasDeclaration {
+        function parseTypeAliasDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): TypeAliasDeclaration {
             const node = <TypeAliasDeclaration>createNode(SyntaxKind.TypeAliasDeclaration, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             parseExpected(SyntaxKind.TypeKeyword);
             node.name = parseIdentifier();
             node.typeParameters = parseTypeParameters();
@@ -5360,10 +5355,10 @@ namespace ts {
             return finishNode(node);
         }
 
-        function parseEnumDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): EnumDeclaration {
+        function parseEnumDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): EnumDeclaration {
             const node = <EnumDeclaration>createNode(SyntaxKind.EnumDeclaration, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             parseExpected(SyntaxKind.EnumKeyword);
             node.name = parseIdentifier();
             if (parseExpected(SyntaxKind.OpenBraceToken)) {
@@ -5388,25 +5383,25 @@ namespace ts {
             return finishNode(node);
         }
 
-        function parseModuleOrNamespaceDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray, flags: NodeFlags): ModuleDeclaration {
+        function parseModuleOrNamespaceDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>, flags: NodeFlags): ModuleDeclaration {
             const node = <ModuleDeclaration>createNode(SyntaxKind.ModuleDeclaration, fullStart);
             // If we are parsing a dotted namespace name, we want to
             // propagate the 'Namespace' flag across the names if set.
             const namespaceFlag = flags & NodeFlags.Namespace;
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             node.flags |= flags;
             node.name = parseIdentifier();
             node.body = parseOptional(SyntaxKind.DotToken)
-                ? parseModuleOrNamespaceDeclaration(getNodePos(), /*decorators*/ undefined, /*modifiers*/ undefined, NodeFlags.Export | namespaceFlag)
+                ? parseModuleOrNamespaceDeclaration(getNodePos(), /*decorators*/ undefined, /*modifiers*/ undefined, NodeFlags.NestedNamespace | namespaceFlag)
                 : parseModuleBlock();
             return finishNode(node);
         }
 
-        function parseAmbientExternalModuleDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ModuleDeclaration {
+        function parseAmbientExternalModuleDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ModuleDeclaration {
             const node = <ModuleDeclaration>createNode(SyntaxKind.ModuleDeclaration, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             if (token() === SyntaxKind.GlobalKeyword) {
                 // parse 'global' as name of global scope augmentation
                 node.name = parseIdentifier();
@@ -5426,8 +5421,8 @@ namespace ts {
             return finishNode(node);
         }
 
-        function parseModuleDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ModuleDeclaration {
-            let flags = modifiers ? modifiers.flags : 0;
+        function parseModuleDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ModuleDeclaration {
+            let flags: NodeFlags = 0;
             if (token() === SyntaxKind.GlobalKeyword) {
                 // global augmentation
                 return parseAmbientExternalModuleDeclaration(fullStart, decorators, modifiers);
@@ -5457,7 +5452,7 @@ namespace ts {
             return nextToken() === SyntaxKind.SlashToken;
         }
 
-        function parseNamespaceExportDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): NamespaceExportDeclaration {
+        function parseNamespaceExportDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): NamespaceExportDeclaration {
             const exportDeclaration = <NamespaceExportDeclaration>createNode(SyntaxKind.NamespaceExportDeclaration, fullStart);
             exportDeclaration.decorators = decorators;
             exportDeclaration.modifiers = modifiers;
@@ -5471,7 +5466,7 @@ namespace ts {
             return finishNode(exportDeclaration);
         }
 
-        function parseImportDeclarationOrImportEqualsDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ImportEqualsDeclaration | ImportDeclaration {
+        function parseImportDeclarationOrImportEqualsDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ImportEqualsDeclaration | ImportDeclaration {
             parseExpected(SyntaxKind.ImportKeyword);
             const afterImportPos = scanner.getStartPos();
 
@@ -5484,7 +5479,7 @@ namespace ts {
                     // import x = M.x;
                     const importEqualsDeclaration = <ImportEqualsDeclaration>createNode(SyntaxKind.ImportEqualsDeclaration, fullStart);
                     importEqualsDeclaration.decorators = decorators;
-                    setModifiers(importEqualsDeclaration, modifiers);
+                    importEqualsDeclaration.modifiers = modifiers;
                     importEqualsDeclaration.name = identifier;
                     parseExpected(SyntaxKind.EqualsToken);
                     importEqualsDeclaration.moduleReference = parseModuleReference();
@@ -5496,7 +5491,7 @@ namespace ts {
             // Import statement
             const importDeclaration = <ImportDeclaration>createNode(SyntaxKind.ImportDeclaration, fullStart);
             importDeclaration.decorators = decorators;
-            setModifiers(importDeclaration, modifiers);
+            importDeclaration.modifiers = modifiers;
 
             // ImportDeclaration:
             //  import ImportClause from ModuleSpecifier ;
@@ -5632,10 +5627,10 @@ namespace ts {
             return finishNode(node);
         }
 
-        function parseExportDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ExportDeclaration {
+        function parseExportDeclaration(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ExportDeclaration {
             const node = <ExportDeclaration>createNode(SyntaxKind.ExportDeclaration, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             if (parseOptional(SyntaxKind.AsteriskToken)) {
                 parseExpected(SyntaxKind.FromKeyword);
                 node.moduleSpecifier = parseModuleSpecifier();
@@ -5655,10 +5650,10 @@ namespace ts {
             return finishNode(node);
         }
 
-        function parseExportAssignment(fullStart: number, decorators: NodeArray<Decorator>, modifiers: ModifiersArray): ExportAssignment {
+        function parseExportAssignment(fullStart: number, decorators: NodeArray<Decorator>, modifiers: NodeArray<Modifier>): ExportAssignment {
             const node = <ExportAssignment>createNode(SyntaxKind.ExportAssignment, fullStart);
             node.decorators = decorators;
-            setModifiers(node, modifiers);
+            node.modifiers = modifiers;
             if (parseOptional(SyntaxKind.EqualsToken)) {
                 node.isExportEquals = true;
             }
@@ -5744,7 +5739,7 @@ namespace ts {
 
         function setExternalModuleIndicator(sourceFile: SourceFile) {
             sourceFile.externalModuleIndicator = forEach(sourceFile.statements, node =>
-                node.flags & NodeFlags.Export
+                hasModifier(node, ModifierFlags.Export)
                     || node.kind === SyntaxKind.ImportEqualsDeclaration && (<ImportEqualsDeclaration>node).moduleReference.kind === SyntaxKind.ExternalModuleReference
                     || node.kind === SyntaxKind.ImportDeclaration
                     || node.kind === SyntaxKind.ExportAssignment
@@ -6084,10 +6079,8 @@ namespace ts {
             function parseJSDocTypeList(firstType: JSDocType) {
                 Debug.assert(!!firstType);
 
-                const types = <NodeArray<JSDocType>>[];
-                types.pos = firstType.pos;
+                const types = createNodeArray([firstType], firstType.pos);
 
-                types.push(firstType);
                 while (parseOptional(SyntaxKind.BarToken)) {
                     types.push(parseJSDocType());
                 }
@@ -6302,11 +6295,11 @@ namespace ts {
                 function addTag(tag: JSDocTag): void {
                     if (tag) {
                         if (!tags) {
-                            tags = <NodeArray<JSDocTag>>[];
-                            tags.pos = tag.pos;
+                            tags = createNodeArray([tag], tag.pos);
+                        }
+                        else {
+                            tags.push(tag);
                         }
-
-                        tags.push(tag);
                         tags.end = tag.end;
                     }
                 }
@@ -6518,8 +6511,7 @@ namespace ts {
                     }
 
                     // Type parameter list looks like '@template T,U,V'
-                    const typeParameters = <NodeArray<TypeParameterDeclaration>>[];
-                    typeParameters.pos = scanner.getStartPos();
+                    const typeParameters = createNodeArray<TypeParameterDeclaration>();
 
                     while (true) {
                         const name = parseJSDocIdentifierName();

src/compiler/program.ts

@@ -8,11 +8,9 @@ namespace ts {
 
     const emptyArray: any[] = [];
 
-    const defaultTypeRoots = ["node_modules/@types"];
-
-    export function findConfigFile(searchPath: string, fileExists: (fileName: string) => boolean): string {
+    export function findConfigFile(searchPath: string, fileExists: (fileName: string) => boolean, configName = "tsconfig.json"): string {
         while (true) {
-            const fileName = combinePaths(searchPath, "tsconfig.json");
+            const fileName = combinePaths(searchPath, configName);
             if (fileExists(fileName)) {
                 return fileName;
             }
@@ -168,7 +166,7 @@ namespace ts {
 
     const typeReferenceExtensions = [".d.ts"];
 
-    function getEffectiveTypeRoots(options: CompilerOptions, host: ModuleResolutionHost) {
+    export function getEffectiveTypeRoots(options: CompilerOptions, host: { directoryExists?: (directoryName: string) => boolean, getCurrentDirectory?: () => string }): string[] | undefined  {
         if (options.typeRoots) {
             return options.typeRoots;
         }
@@ -181,12 +179,38 @@ namespace ts {
             currentDirectory = host.getCurrentDirectory();
         }
 
-        if (!currentDirectory) {
-            return undefined;
-        }
-        return map(defaultTypeRoots, d => combinePaths(currentDirectory, d));
+        return currentDirectory && getDefaultTypeRoots(currentDirectory, host);
     }
 
+    /**
+     * Returns the path to every node_modules/@types directory from some ancestor directory.
+     * Returns undefined if there are none.
+     */
+    function getDefaultTypeRoots(currentDirectory: string,  host: { directoryExists?: (directoryName: string) => boolean }): string[] | undefined {
+        if (!host.directoryExists) {
+            return [combinePaths(currentDirectory, nodeModulesAtTypes)];
+            // And if it doesn't exist, tough.
+        }
+
+        let typeRoots: string[];
+
+        while (true) {
+            const atTypes = combinePaths(currentDirectory, nodeModulesAtTypes);
+            if (host.directoryExists(atTypes)) {
+                (typeRoots || (typeRoots = [])).push(atTypes);
+            }
+
+            const parent = getDirectoryPath(currentDirectory);
+            if (parent === currentDirectory) {
+                break;
+            }
+            currentDirectory = parent;
+        }
+
+        return typeRoots;
+    }
+    const nodeModulesAtTypes = combinePaths("node_modules", "@types");
+
     /**
      * @param {string | undefined} containingFile - file that contains type reference directive, can be undefined if containing file is unknown.
      * This is possible in case if resolution is performed for directives specified via 'types' parameter. In this case initial path for secondary lookups
@@ -963,6 +987,7 @@ namespace ts {
             readFile: fileName => sys.readFile(fileName),
             trace: (s: string) => sys.write(s + newLine),
             directoryExists: directoryName => sys.directoryExists(directoryName),
+            getEnvironmentVariable: name => getEnvironmentVariable(name, /*host*/ undefined),
             getDirectories: (path: string) => sys.getDirectories(path),
             realpath
         };
@@ -1706,7 +1731,7 @@ namespace ts {
                     return false;
                 }
 
-                function checkModifiers(modifiers: ModifiersArray): boolean {
+                function checkModifiers(modifiers: NodeArray<Modifier>): boolean {
                     if (modifiers) {
                         for (const modifier of modifiers) {
                             switch (modifier.kind) {
@@ -1790,6 +1815,17 @@ namespace ts {
             let imports: LiteralExpression[];
             let moduleAugmentations: LiteralExpression[];
 
+            // If we are importing helpers, we need to add a synthetic reference to resolve the
+            // helpers library.
+            if (options.importHelpers
+                && (options.isolatedModules || isExternalModuleFile)
+                && !file.isDeclarationFile) {
+                const externalHelpersModuleReference = <StringLiteral>createNode(SyntaxKind.StringLiteral);
+                externalHelpersModuleReference.text = externalHelpersModuleNameText;
+                externalHelpersModuleReference.parent = file;
+                imports = [externalHelpersModuleReference];
+            }
+
             for (const node of file.statements) {
                 collectModuleReferences(node, /*inAmbientModule*/ false);
                 if (isJavaScriptFile) {
@@ -1823,7 +1859,7 @@ namespace ts {
                         }
                         break;
                     case SyntaxKind.ModuleDeclaration:
-                        if (isAmbientModule(<ModuleDeclaration>node) && (inAmbientModule || node.flags & NodeFlags.Ambient || isDeclarationFile(file))) {
+                        if (isAmbientModule(<ModuleDeclaration>node) && (inAmbientModule || hasModifier(node, ModifierFlags.Ambient) || isDeclarationFile(file))) {
                             const moduleName = <LiteralExpression>(<ModuleDeclaration>node).name;
                             // Ambient module declarations can be interpreted as augmentations for some existing external modules.
                             // This will happen in two cases:
@@ -2306,7 +2342,7 @@ namespace ts {
                 programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "emitDecoratorMetadata", "experimentalDecorators"));
             }
 
-            if (options.reactNamespace && !isIdentifier(options.reactNamespace, languageVersion)) {
+            if (options.reactNamespace && !isIdentifierText(options.reactNamespace, languageVersion)) {
                 programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Invalid_value_for_reactNamespace_0_is_not_a_valid_identifier, options.reactNamespace));
             }
 

src/compiler/scanner.ts

@@ -439,9 +439,7 @@ namespace ts {
 
       /* @internal */
       export function skipTrivia(text: string, pos: number, stopAfterLineBreak?: boolean, stopAtComments = false): number {
-          // Using ! with a greater than test is a fast way of testing the following conditions:
-          //  pos === undefined || pos === null || isNaN(pos) || pos < 0;
-          if (!(pos >= 0)) {
+          if (positionIsSynthesized(pos)) {
               return pos;
           }
 
@@ -590,20 +588,34 @@ namespace ts {
     }
 
     /**
-     * Extract comments from text prefixing the token closest following `pos`.
-     * The return value is an array containing a TextRange for each comment.
-     * Single-line comment ranges include the beginning '//' characters but not the ending line break.
-     * Multi - line comment ranges include the beginning '/* and ending '<asterisk>/' characters.
-     * The return value is undefined if no comments were found.
-     * @param trailing
-     * If false, whitespace is skipped until the first line break and comments between that location
-     * and the next token are returned.
-     * If true, comments occurring between the given position and the next line break are returned.
+     * Invokes a callback for each comment range following the provided position.
+     *
+     * Single-line comment ranges include the leading double-slash characters but not the ending
+     * line break. Multi-line comment ranges include the leading slash-asterisk and trailing
+     * asterisk-slash characters.
+     *
+     * @param reduce If true, accumulates the result of calling the callback in a fashion similar
+     *      to reduceLeft. If false, iteration stops when the callback returns a truthy value.
+     * @param text The source text to scan.
+     * @param pos The position at which to start scanning.
+     * @param trailing If false, whitespace is skipped until the first line break and comments
+     *      between that location and the next token are returned. If true, comments occurring
+     *      between the given position and the next line break are returned.
+     * @param cb The callback to execute as each comment range is encountered.
+     * @param state A state value to pass to each iteration of the callback.
+     * @param initial An initial value to pass when accumulating results (when "reduce" is true).
+     * @returns If "reduce" is true, the accumulated value. If "reduce" is false, the first truthy
+     *      return value of the callback.
      */
-    function getCommentRanges(text: string, pos: number, trailing: boolean): CommentRange[] {
-        let result: CommentRange[];
+    function iterateCommentRanges<T, U>(reduce: boolean, text: string, pos: number, trailing: boolean, cb: (pos: number, end: number, kind: SyntaxKind, hasTrailingNewLine: boolean, state: T, memo: U) => U, state: T, initial?: U): U {
+        let pendingPos: number;
+        let pendingEnd: number;
+        let pendingKind: SyntaxKind;
+        let pendingHasTrailingNewLine: boolean;
+        let hasPendingCommentRange = false;
         let collecting = trailing || pos === 0;
-        while (pos < text.length) {
+        let accumulator = initial;
+        scan: while (pos >= 0 && pos < text.length) {
             const ch = text.charCodeAt(pos);
             switch (ch) {
                 case CharacterCodes.carriageReturn:
@@ -613,12 +625,14 @@ namespace ts {
                 case CharacterCodes.lineFeed:
                     pos++;
                     if (trailing) {
-                        return result;
+                        break scan;
                     }
+
                     collecting = true;
-                    if (result && result.length) {
-                        lastOrUndefined(result).hasTrailingNewLine = true;
+                    if (hasPendingCommentRange) {
+                        pendingHasTrailingNewLine = true;
                     }
+
                     continue;
                 case CharacterCodes.tab:
                 case CharacterCodes.verticalTab:
@@ -651,38 +665,78 @@ namespace ts {
                                 pos++;
                             }
                         }
+
                         if (collecting) {
-                            if (!result) {
-                                result = [];
+                            if (hasPendingCommentRange) {
+                                accumulator = cb(pendingPos, pendingEnd, pendingKind, pendingHasTrailingNewLine, state, accumulator);
+                                if (!reduce && accumulator) {
+                                    // If we are not reducing and we have a truthy result, return it.
+                                    return accumulator;
+                                }
+
+                                hasPendingCommentRange = false;
                             }
 
-                            result.push({ pos: startPos, end: pos, hasTrailingNewLine, kind });
+                            pendingPos = startPos;
+                            pendingEnd = pos;
+                            pendingKind = kind;
+                            pendingHasTrailingNewLine = hasTrailingNewLine;
+                            hasPendingCommentRange = true;
                         }
+
                         continue;
                     }
-                    break;
+                    break scan;
                 default:
                     if (ch > CharacterCodes.maxAsciiCharacter && (isWhiteSpace(ch))) {
-                        if (result && result.length && isLineBreak(ch)) {
-                            lastOrUndefined(result).hasTrailingNewLine = true;
+                        if (hasPendingCommentRange && isLineBreak(ch)) {
+                            pendingHasTrailingNewLine = true;
                         }
                         pos++;
                         continue;
                     }
-                    break;
+                    break scan;
             }
-            return result;
         }
 
-        return result;
+        if (hasPendingCommentRange) {
+            accumulator = cb(pendingPos, pendingEnd, pendingKind, pendingHasTrailingNewLine, state, accumulator);
+        }
+
+        return accumulator;
+    }
+
+    export function forEachLeadingCommentRange<T, U>(text: string, pos: number, cb: (pos: number, end: number, kind: SyntaxKind, hasTrailingNewLine: boolean, state: T) => U, state?: T) {
+        return iterateCommentRanges(/*reduce*/ false, text, pos, /*trailing*/ false, cb, state);
+    }
+
+    export function forEachTrailingCommentRange<T, U>(text: string, pos: number, cb: (pos: number, end: number, kind: SyntaxKind, hasTrailingNewLine: boolean, state: T) => U, state?: T) {
+        return iterateCommentRanges(/*reduce*/ false, text, pos, /*trailing*/ true, cb, state);
+    }
+
+    export function reduceEachLeadingCommentRange<T, U>(text: string, pos: number, cb: (pos: number, end: number, kind: SyntaxKind, hasTrailingNewLine: boolean, state: T, memo: U) => U, state: T, initial: U) {
+        return iterateCommentRanges(/*reduce*/ true, text, pos, /*trailing*/ false, cb, state, initial);
+    }
+
+    export function reduceEachTrailingCommentRange<T, U>(text: string, pos: number, cb: (pos: number, end: number, kind: SyntaxKind, hasTrailingNewLine: boolean, state: T, memo: U) => U, state: T, initial: U) {
+        return iterateCommentRanges(/*reduce*/ true, text, pos, /*trailing*/ true, cb, state, initial);
+    }
+
+    function appendCommentRange(pos: number, end: number, kind: SyntaxKind, hasTrailingNewLine: boolean, state: any, comments: CommentRange[]) {
+        if (!comments) {
+            comments = [];
+        }
+
+        comments.push({ pos, end, hasTrailingNewLine, kind });
+        return comments;
     }
 
     export function getLeadingCommentRanges(text: string, pos: number): CommentRange[] {
-        return getCommentRanges(text, pos, /*trailing*/ false);
+        return reduceEachLeadingCommentRange(text, pos, appendCommentRange, undefined, undefined);
     }
 
     export function getTrailingCommentRanges(text: string, pos: number): CommentRange[] {
-        return getCommentRanges(text, pos, /*trailing*/ true);
+        return reduceEachTrailingCommentRange(text, pos, appendCommentRange, undefined, undefined);
     }
 
     /** Optionally, get the shebang */
@@ -705,7 +759,7 @@ namespace ts {
     }
 
     /* @internal */
-    export function isIdentifier(name: string, languageVersion: ScriptTarget): boolean {
+    export function isIdentifierText(name: string, languageVersion: ScriptTarget): boolean {
         if (!isIdentifierStart(name.charCodeAt(0), languageVersion)) {
             return false;
         }

src/compiler/sourcemap.ts

@@ -3,19 +3,211 @@
 /* @internal */
 namespace ts {
     export interface SourceMapWriter {
-        getSourceMapData(): SourceMapData;
-        setSourceFile(sourceFile: SourceFile): void;
-        emitPos(pos: number): void;
-        emitStart(range: TextRange): void;
-        emitEnd(range: TextRange, stopOverridingSpan?: boolean): void;
-        changeEmitSourcePos(): void;
-        getText(): string;
-        getSourceMappingURL(): string;
+        /**
+         * Initialize the SourceMapWriter for a new output file.
+         *
+         * @param filePath The path to the generated output file.
+         * @param sourceMapFilePath The path to the output source map file.
+         * @param sourceFiles The input source files for the program.
+         * @param isBundledEmit A value indicating whether the generated output file is a bundle.
+         */
         initialize(filePath: string, sourceMapFilePath: string, sourceFiles: SourceFile[], isBundledEmit: boolean): void;
+
+        /**
+         * Reset the SourceMapWriter to an empty state.
+         */
         reset(): void;
+
+        /**
+         * Gets test data for source maps.
+         */
+        getSourceMapData(): SourceMapData;
+
+        /**
+         * Set the current source file.
+         *
+         * @param sourceFile The source file.
+         */
+        setSourceFile(sourceFile: SourceFile): void;
+
+        /**
+         * Emits a mapping.
+         *
+         * If the position is synthetic (undefined or a negative value), no mapping will be
+         * created.
+         *
+         * @param pos The position.
+         */
+        emitPos(pos: number): void;
+
+        /**
+         * Emits a mapping for the start of a range.
+         *
+         * If the range's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param range The range to emit.
+         */
+        emitStart(range: TextRange): void;
+
+        /**
+         * Emits a mapping for the start of a range.
+         *
+         * If the node's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param range The range to emit.
+         * @param contextNode The node for the current range.
+         * @param ignoreNodeCallback A callback used to determine whether to skip source map
+         *        emit for the start position of this node.
+         * @param ignoreChildrenCallback A callback used to determine whether to skip source
+         *        map emit for all children of this node.
+         * @param getTextRangeCallbackCallback A callback used to get a custom source map
+         *        range for this node.
+         */
+        emitStart(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallbackCallback: (node: Node) => TextRange): void;
+
+        /**
+         * Emits a mapping for the end of a range.
+         *
+         * If the range's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param range The range to emit.
+         */
+        emitEnd(range: TextRange): void;
+
+        /**
+         * Emits a mapping for the end of a range.
+         *
+         * If the node's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param range The range to emit.
+         * @param contextNode The node for the current range.
+         * @param ignoreNodeCallback A callback used to determine whether to skip source map
+         *        emit for the end position of this node.
+         * @param ignoreChildrenCallback A callback used to determine whether to skip source
+         *        map emit for all children of this node.
+         * @param getTextRangeCallbackCallback A callback used to get a custom source map
+         *        range for this node.
+         */
+        emitEnd(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallbackCallback: (node: Node) => TextRange): void;
+
+        /**
+         * Emits a mapping for the start position of a token.
+         *
+         * If the token's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param token The token to emit.
+         * @param tokenStartPos The start position of the token.
+         * @returns The start position of the token, following any trivia.
+         */
+        emitTokenStart(token: SyntaxKind, tokenStartPos: number): number;
+
+        /**
+         * Emits a mapping for the start position of a token.
+         *
+         * If the token's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param token The token to emit.
+         * @param tokenStartPos The start position of the token.
+         * @param contextNode The node containing this token.
+         * @param ignoreTokenCallback A callback used to determine whether to skip source map
+         *        emit for the start position of this token.
+         * @param getTokenTextRangeCallback A callback used to get a custom source
+         *        map range for this node.
+         * @returns The start position of the token, following any trivia.
+         */
+        emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
+
+        /**
+         * Emits a mapping for the end position of a token.
+         *
+         * If the token's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param token The token to emit.
+         * @param tokenEndPos The end position of the token.
+         * @returns The end position of the token.
+         */
+        emitTokenEnd(token: SyntaxKind, tokenEndPos: number): number;
+
+        /**
+         * Emits a mapping for the end position of a token.
+         *
+         * If the token's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param token The token to emit.
+         * @param tokenEndPos The end position of the token.
+         * @param contextNode The node containing this token.
+         * @param ignoreTokenCallback A callback used to determine whether to skip source map
+         *        emit for the end position of this token.
+         * @param getTokenTextRangeCallback A callback used to get a custom source
+         *        map range for this node.
+         * @returns The end position of the token.
+         */
+        emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
+
+        /*@deprecated*/ changeEmitSourcePos(): void;
+        /*@deprecated*/ stopOverridingSpan(): void;
+
+        /**
+         * Gets the text for the source map.
+         */
+        getText(): string;
+
+        /**
+         * Gets the SourceMappingURL for the source map.
+         */
+        getSourceMappingURL(): string;
+    }
+
+    export function createSourceMapWriter(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
+        const compilerOptions = host.getCompilerOptions();
+        if (compilerOptions.sourceMap || compilerOptions.inlineSourceMap) {
+            if (compilerOptions.extendedDiagnostics) {
+                return createSourceMapWriterWithExtendedDiagnostics(host, writer);
+            }
+
+            return createSourceMapWriterWorker(host, writer);
+        }
+        else {
+            return getNullSourceMapWriter();
+        }
     }
 
     let nullSourceMapWriter: SourceMapWriter;
+
+    export function getNullSourceMapWriter(): SourceMapWriter {
+        if (nullSourceMapWriter === undefined) {
+            nullSourceMapWriter = {
+                initialize(filePath: string, sourceMapFilePath: string, sourceFiles: SourceFile[], isBundledEmit: boolean): void { },
+                reset(): void { },
+                getSourceMapData(): SourceMapData { return undefined; },
+                setSourceFile(sourceFile: SourceFile): void { },
+                emitPos(pos: number): void { },
+                emitStart(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void { },
+                emitEnd(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void { },
+                emitTokenStart(token: SyntaxKind, pos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number { return -1; },
+                emitTokenEnd(token: SyntaxKind, end: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number { return -1; },
+                changeEmitSourcePos(): void { },
+                stopOverridingSpan(): void { },
+                getText(): string { return undefined; },
+                getSourceMappingURL(): string { return undefined; }
+            };
+        }
+
+        return nullSourceMapWriter;
+    }
+
     // Used for initialize lastEncodedSourceMapSpan and reset lastEncodedSourceMapSpan when updateLastEncodedAndRecordedSpans
     const defaultLastEncodedSourceMapSpan: SourceMapSpan = {
         emittedLine: 1,
@@ -25,29 +217,11 @@ namespace ts {
         sourceIndex: 0
     };
 
-    export function getNullSourceMapWriter(): SourceMapWriter {
-        if (nullSourceMapWriter === undefined) {
-            nullSourceMapWriter = {
-                getSourceMapData(): SourceMapData { return undefined; },
-                setSourceFile(sourceFile: SourceFile): void { },
-                emitStart(range: TextRange): void { },
-                emitEnd(range: TextRange, stopOverridingSpan?: boolean): void { },
-                emitPos(pos: number): void { },
-                changeEmitSourcePos(): void { },
-                getText(): string { return undefined; },
-                getSourceMappingURL(): string { return undefined; },
-                initialize(filePath: string, sourceMapFilePath: string, sourceFiles: SourceFile[], isBundledEmit: boolean): void { },
-                reset(): void { },
-            };
-        }
-
-        return nullSourceMapWriter;
-    }
-
-    export function createSourceMapWriter(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
+    function createSourceMapWriterWorker(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
         const compilerOptions = host.getCompilerOptions();
         const extendedDiagnostics = compilerOptions.extendedDiagnostics;
         let currentSourceFile: SourceFile;
+        let currentSourceText: string;
         let sourceMapDir: string; // The directory in which sourcemap will be
         let stopOverridingSpan = false;
         let modifyLastSourcePos = false;
@@ -63,25 +237,45 @@ namespace ts {
         // Source map data
         let sourceMapData: SourceMapData;
 
+        // This keeps track of the number of times `disable` has been called without a
+        // corresponding call to `enable`. As long as this value is non-zero, mappings will not
+        // be recorded.
+        // This is primarily used to provide a better experience when debugging binding
+        // patterns and destructuring assignments for simple expressions.
+        let disableDepth: number;
+
         return {
+            initialize,
+            reset,
             getSourceMapData: () => sourceMapData,
             setSourceFile,
             emitPos,
             emitStart,
             emitEnd,
+            emitTokenStart,
+            emitTokenEnd,
             changeEmitSourcePos,
+            stopOverridingSpan: () => stopOverridingSpan = true,
             getText,
             getSourceMappingURL,
-            initialize,
-            reset,
         };
 
+        /**
+         * Initialize the SourceMapWriter for a new output file.
+         *
+         * @param filePath The path to the generated output file.
+         * @param sourceMapFilePath The path to the output source map file.
+         * @param sourceFiles The input source files for the program.
+         * @param isBundledEmit A value indicating whether the generated output file is a bundle.
+         */
         function initialize(filePath: string, sourceMapFilePath: string, sourceFiles: SourceFile[], isBundledEmit: boolean) {
             if (sourceMapData) {
                 reset();
             }
 
             currentSourceFile = undefined;
+            currentSourceText = undefined;
+            disableDepth = 0;
 
             // Current source map file and its index in the sources list
             sourceMapSourceIndex = -1;
@@ -140,6 +334,9 @@ namespace ts {
             }
         }
 
+        /**
+         * Reset the SourceMapWriter to an empty state.
+         */
         function reset() {
             currentSourceFile = undefined;
             sourceMapDir = undefined;
@@ -148,6 +345,23 @@ namespace ts {
             lastEncodedSourceMapSpan = undefined;
             lastEncodedNameIndex = undefined;
             sourceMapData = undefined;
+            disableDepth = 0;
+        }
+
+        /**
+         * Re-enables the recording of mappings.
+         */
+        function enable() {
+            if (disableDepth > 0) {
+                disableDepth--;
+            }
+        }
+
+        /**
+         * Disables the recording of mappings.
+         */
+        function disable() {
+            disableDepth++;
         }
 
         function updateLastEncodedAndRecordedSpans() {
@@ -236,8 +450,16 @@ namespace ts {
             sourceMapData.sourceMapDecodedMappings.push(lastEncodedSourceMapSpan);
         }
 
+        /**
+         * Emits a mapping.
+         *
+         * If the position is synthetic (undefined or a negative value), no mapping will be
+         * created.
+         *
+         * @param pos The position.
+         */
         function emitPos(pos: number) {
-            if (pos === -1) {
+            if (positionIsSynthesized(pos) || disableDepth > 0) {
                 return;
             }
 
@@ -291,27 +513,201 @@ namespace ts {
             }
         }
 
-        function getStartPos(range: TextRange) {
+        function getStartPosPastDecorators(range: TextRange) {
             const rangeHasDecorators = !!(range as Node).decorators;
-            return range.pos !== -1 ? skipTrivia(currentSourceFile.text, rangeHasDecorators ? (range as Node).decorators.end : range.pos) : -1;
+            return skipTrivia(currentSourceText, rangeHasDecorators ? (range as Node).decorators.end : range.pos);
         }
 
-        function emitStart(range: TextRange) {
-            emitPos(getStartPos(range));
+        /**
+         * Emits a mapping for the start of a range.
+         *
+         * If the range's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param range The range to emit.0
+         */
+        function emitStart(range: TextRange): void;
+        /**
+         * Emits a mapping for the start of a range.
+         *
+         * If the node's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param range The range to emit.
+         * @param contextNode The node for the current range.
+         * @param ignoreNodeCallback A callback used to determine whether to skip source map
+         *        emit for the start position of this node.
+         * @param ignoreChildrenCallback A callback used to determine whether to skip source
+         *        map emit for all children of this node.
+         * @param getTextRangeCallbackCallback A callback used to get a custom source map
+         *        range for this node.
+         */
+        function emitStart(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallback: (node: Node) => TextRange): void;
+        function emitStart(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange) {
+            if (contextNode) {
+                if (!ignoreNodeCallback(contextNode)) {
+                    range = getTextRangeCallback(contextNode) || range;
+                    emitPos(getStartPosPastDecorators(range));
+                }
+
+                if (ignoreChildrenCallback(contextNode)) {
+                    disable();
+                }
+            }
+            else {
+                emitPos(getStartPosPastDecorators(range));
+            }
         }
 
-        function emitEnd(range: TextRange, stopOverridingEnd?: boolean) {
-            emitPos(range.end);
-            stopOverridingSpan = stopOverridingEnd;
+        /**
+         * Emits a mapping for the end of a range.
+         *
+         * If the range's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param range The range to emit.
+         */
+        function emitEnd(range: TextRange): void;
+        /**
+         * Emits a mapping for the end of a range.
+         *
+         * If the node's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param range The range to emit.
+         * @param contextNode The node for the current range.
+         * @param ignoreNodeCallback A callback used to determine whether to skip source map
+         *        emit for the end position of this node.
+         * @param ignoreChildrenCallback A callback used to determine whether to skip source
+         *        map emit for all children of this node.
+         * @param getTextRangeCallbackCallback A callback used to get a custom source map
+         *        range for this node.
+         */
+        function emitEnd(range: TextRange, contextNode: Node, ignoreNodeCallback: (node: Node) => boolean, ignoreChildrenCallback: (node: Node) => boolean, getTextRangeCallback: (node: Node) => TextRange): void;
+        function emitEnd(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange) {
+            if (contextNode) {
+                if (ignoreChildrenCallback(contextNode)) {
+                    enable();
+                }
+
+                if (!ignoreNodeCallback(contextNode)) {
+                    range = getTextRangeCallback(contextNode) || range;
+                    emitPos(range.end);
+                }
+            }
+            else {
+                emitPos(range.end);
+            }
+
+            stopOverridingSpan = false;
         }
 
+        /**
+         * Emits a mapping for the start position of a token.
+         *
+         * If the token's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param token The token to emit.
+         * @param tokenStartPos The start position of the token.
+         * @returns The start position of the token, following any trivia.
+         */
+        function emitTokenStart(token: SyntaxKind, tokenStartPos: number): number;
+        /**
+         * Emits a mapping for the start position of a token.
+         *
+         * If the token's start position is synthetic (undefined or a negative value), no mapping
+         * will be created. Any trivia at the start position in the original source will be
+         * skipped.
+         *
+         * @param token The token to emit.
+         * @param tokenStartPos The start position of the token.
+         * @param contextNode The node containing this token.
+         * @param ignoreTokenCallback A callback used to determine whether to skip source map
+         *        emit for the start position of this token.
+         * @param getTokenTextRangeCallback A callback used to get a custom source
+         *        map range for this node.
+         * @returns The start position of the token, following any trivia.
+         */
+        function emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
+        function emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
+            if (contextNode) {
+                if (ignoreTokenCallback(contextNode, token)) {
+                    return skipTrivia(currentSourceText, tokenStartPos);
+                }
+
+                const range = getTokenTextRangeCallback(contextNode, token);
+                if (range) {
+                    tokenStartPos = range.pos;
+                }
+            }
+
+            tokenStartPos = skipTrivia(currentSourceText, tokenStartPos);
+            emitPos(tokenStartPos);
+            return tokenStartPos;
+        }
+
+        /**
+         * Emits a mapping for the end position of a token.
+         *
+         * If the token's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param token The token to emit.
+         * @param tokenEndPos The end position of the token.
+         * @returns The end position of the token.
+         */
+        function emitTokenEnd(token: SyntaxKind, tokenEndPos: number): number;
+        /**
+         * Emits a mapping for the end position of a token.
+         *
+         * If the token's end position is synthetic (undefined or a negative value), no mapping
+         * will be created.
+         *
+         * @param token The token to emit.
+         * @param tokenEndPos The end position of the token.
+         * @param contextNode The node containing this token.
+         * @param ignoreTokenCallback A callback used to determine whether to skip source map
+         *        emit for the end position of this token.
+         * @param getTokenTextRangeCallback A callback used to get a custom source
+         *        map range for this node.
+         * @returns The end position of the token.
+         */
+        function emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode: Node, ignoreTokenCallback: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback: (node: Node, token: SyntaxKind) => TextRange): number;
+        function emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node, token: SyntaxKind) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
+            if (contextNode) {
+                if (ignoreTokenCallback(contextNode, token)) {
+                    return tokenEndPos;
+                }
+
+                const range = getTokenTextRangeCallback(contextNode, token);
+                if (range) {
+                    tokenEndPos = range.end;
+                }
+            }
+
+            emitPos(tokenEndPos);
+            return tokenEndPos;
+        }
+
+
+        // @deprecated
         function changeEmitSourcePos() {
             Debug.assert(!modifyLastSourcePos);
             modifyLastSourcePos = true;
         }
 
+        /**
+         * Set the current source file.
+         *
+         * @param sourceFile The source file.
+         */
         function setSourceFile(sourceFile: SourceFile) {
             currentSourceFile = sourceFile;
+            currentSourceText = currentSourceFile.text;
 
             // Add the file to tsFilePaths
             // If sourceroot option: Use the relative path corresponding to the common directory path
@@ -330,14 +726,17 @@ namespace ts {
                 sourceMapData.sourceMapSources.push(source);
 
                 // The one that can be used from program to get the actual source file
-                sourceMapData.inputSourceFileNames.push(sourceFile.fileName);
+                sourceMapData.inputSourceFileNames.push(currentSourceFile.fileName);
 
                 if (compilerOptions.inlineSources) {
-                    sourceMapData.sourceMapSourcesContent.push(sourceFile.text);
+                    sourceMapData.sourceMapSourcesContent.push(currentSourceFile.text);
                 }
             }
         }
 
+        /**
+         * Gets the text for the source map.
+         */
         function getText() {
             encodeLastRecordedSourceMapSpan();
 
@@ -352,6 +751,9 @@ namespace ts {
             });
         }
 
+        /**
+         * Gets the SourceMappingURL for the source map.
+         */
         function getSourceMappingURL() {
             if (compilerOptions.inlineSourceMap) {
                 // Encode the sourceMap into the sourceMap url
@@ -364,6 +766,61 @@ namespace ts {
         }
     }
 
+    function createSourceMapWriterWithExtendedDiagnostics(host: EmitHost, writer: EmitTextWriter): SourceMapWriter {
+        const {
+            initialize,
+            reset,
+            getSourceMapData,
+            setSourceFile,
+            emitPos,
+            emitStart,
+            emitEnd,
+            emitTokenStart,
+            emitTokenEnd,
+            changeEmitSourcePos,
+            stopOverridingSpan,
+            getText,
+            getSourceMappingURL,
+        } = createSourceMapWriterWorker(host, writer);
+        return {
+            initialize,
+            reset,
+            getSourceMapData,
+            setSourceFile,
+            emitPos(pos: number): void {
+                 performance.mark("sourcemapStart");
+                emitPos(pos);
+                performance.measure("sourceMapTime", "sourcemapStart");
+            },
+            emitStart(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void {
+                performance.mark("emitSourcemap:emitStart");
+                emitStart(range, contextNode, ignoreNodeCallback, ignoreChildrenCallback, getTextRangeCallback);
+                performance.measure("sourceMapTime", "emitSourcemap:emitStart");
+            },
+            emitEnd(range: TextRange, contextNode?: Node, ignoreNodeCallback?: (node: Node) => boolean, ignoreChildrenCallback?: (node: Node) => boolean, getTextRangeCallback?: (node: Node) => TextRange): void {
+                performance.mark("emitSourcemap:emitEnd");
+                emitEnd(range, contextNode, ignoreNodeCallback, ignoreChildrenCallback, getTextRangeCallback);
+                performance.measure("sourceMapTime", "emitSourcemap:emitEnd");
+            },
+            emitTokenStart(token: SyntaxKind, tokenStartPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
+                performance.mark("emitSourcemap:emitTokenStart");
+                tokenStartPos = emitTokenStart(token, tokenStartPos, contextNode, ignoreTokenCallback, getTokenTextRangeCallback);
+                performance.measure("sourceMapTime", "emitSourcemap:emitTokenStart");
+                return tokenStartPos;
+            },
+            emitTokenEnd(token: SyntaxKind, tokenEndPos: number, contextNode?: Node, ignoreTokenCallback?: (node: Node) => boolean, getTokenTextRangeCallback?: (node: Node, token: SyntaxKind) => TextRange): number {
+                performance.mark("emitSourcemap:emitTokenEnd");
+                tokenEndPos = emitTokenEnd(token, tokenEndPos, contextNode, ignoreTokenCallback, getTokenTextRangeCallback);
+                performance.measure("sourceMapTime", "emitSourcemap:emitTokenEnd");
+                return tokenEndPos;
+            },
+            changeEmitSourcePos,
+            stopOverridingSpan,
+            getText,
+            getSourceMappingURL,
+        };
+    }
+
     const base64Chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
     function base64FormatEncode(inValue: number) {

src/compiler/sys.ts

@@ -32,6 +32,8 @@ namespace ts {
         getMemoryUsage?(): number;
         exit(exitCode?: number): void;
         realpath?(path: string): string;
+        /*@internal*/ getEnvironmentVariable(name: string): string;
+        /*@internal*/ tryEnableSourceMapsForHost?(): void;
     }
 
     export interface FileWatcher {
@@ -78,6 +80,7 @@ namespace ts {
         watchFile?(path: string, callback: FileWatcherCallback): FileWatcher;
         watchDirectory?(path: string, callback: DirectoryWatcherCallback, recursive?: boolean): FileWatcher;
         realpath(path: string): string;
+        getEnvironmentVariable?(name: string): string;
     };
 
     export var sys: System = (function() {
@@ -212,6 +215,9 @@ namespace ts {
                     return shell.CurrentDirectory;
                 },
                 getDirectories,
+                getEnvironmentVariable(name: string) {
+                    return new ActiveXObject("WScript.Shell").ExpandEnvironmentStrings(`%${name}%`);
+                },
                 readDirectory,
                 exit(exitCode?: number): void {
                     try {
@@ -267,7 +273,7 @@ namespace ts {
                 }
 
                 function addFileWatcherCallback(filePath: string, callback: FileWatcherCallback): void {
-                    (fileWatcherCallbacks[filePath] || (fileWatcherCallbacks[filePath] = [])).push(callback);
+                    multiMapAdd(fileWatcherCallbacks, filePath, callback);
                 }
 
                 function addFile(fileName: string, callback: FileWatcherCallback): WatchedFile {
@@ -283,16 +289,7 @@ namespace ts {
                 }
 
                 function removeFileWatcherCallback(filePath: string, callback: FileWatcherCallback) {
-                    const callbacks = fileWatcherCallbacks[filePath];
-                    if (callbacks) {
-                        const newCallbacks = copyListRemovingItem(callback, callbacks);
-                        if (newCallbacks.length === 0) {
-                            delete fileWatcherCallbacks[filePath];
-                        }
-                        else {
-                            fileWatcherCallbacks[filePath] = newCallbacks;
-                        }
-                    }
+                    multiMapRemove(fileWatcherCallbacks, filePath, callback);
                 }
 
                 function fileEventHandler(eventName: string, relativeFileName: string, baseDirPath: string) {
@@ -432,7 +429,7 @@ namespace ts {
             }
 
             function getDirectories(path: string): string[] {
-                return filter<string>(_fs.readdirSync(path), p => fileSystemEntryExists(combinePaths(path, p), FileSystemEntryKind.Directory));
+                return filter<string>(_fs.readdirSync(path), dir => fileSystemEntryExists(combinePaths(path, dir), FileSystemEntryKind.Directory));
             }
 
             const nodeSystem: System = {
@@ -508,6 +505,9 @@ namespace ts {
                     return process.cwd();
                 },
                 getDirectories,
+                getEnvironmentVariable(name: string) {
+                    return process.env[name] || "";
+                },
                 readDirectory,
                 getModifiedTime(path) {
                     try {
@@ -543,6 +543,14 @@ namespace ts {
                 },
                 realpath(path: string): string {
                     return _fs.realpathSync(path);
+                },
+                tryEnableSourceMapsForHost() {
+                    try {
+                        require("source-map-support").install();
+                    }
+                    catch (e) {
+                        // Could not enable source maps.
+                    }
                 }
             };
             return nodeSystem;
@@ -574,6 +582,7 @@ namespace ts {
                 getExecutingFilePath: () => ChakraHost.executingFile,
                 getCurrentDirectory: () => ChakraHost.currentDirectory,
                 getDirectories: ChakraHost.getDirectories,
+                getEnvironmentVariable: ChakraHost.getEnvironmentVariable || ((name: string) => ""),
                 readDirectory: (path: string, extensions?: string[], excludes?: string[], includes?: string[]) => {
                     const pattern = getFileMatcherPatterns(path, extensions, excludes, includes, !!ChakraHost.useCaseSensitiveFileNames, ChakraHost.currentDirectory);
                     return ChakraHost.readDirectory(path, extensions, pattern.basePaths, pattern.excludePattern, pattern.includeFilePattern, pattern.includeDirectoryPattern);

src/compiler/transformer.ts

@@ -0,0 +1,632 @@
+/// <reference path="visitor.ts" />
+/// <reference path="transformers/ts.ts" />
+/// <reference path="transformers/jsx.ts" />
+/// <reference path="transformers/es7.ts" />
+/// <reference path="transformers/es6.ts" />
+/// <reference path="transformers/generators.ts" />
+/// <reference path="transformers/module/module.ts" />
+/// <reference path="transformers/module/system.ts" />
+/// <reference path="transformers/module/es6.ts" />
+
+/* @internal */
+namespace ts {
+    const moduleTransformerMap = createMap<Transformer>({
+        [ModuleKind.ES6]: transformES6Module,
+        [ModuleKind.System]: transformSystemModule,
+        [ModuleKind.AMD]: transformModule,
+        [ModuleKind.CommonJS]: transformModule,
+        [ModuleKind.UMD]: transformModule,
+        [ModuleKind.None]: transformModule,
+    });
+
+    const enum SyntaxKindFeatureFlags {
+        Substitution = 1 << 0,
+        EmitNotifications = 1 << 1,
+    }
+
+    export interface TransformationResult {
+        /**
+         * Gets the transformed source files.
+         */
+        getSourceFiles(): SourceFile[];
+
+        /**
+         * Gets the TextRange to use for source maps for a token of a node.
+         */
+        getTokenSourceMapRange(node: Node, token: SyntaxKind): TextRange;
+
+        /**
+         * Determines whether expression substitutions are enabled for the provided node.
+         */
+        isSubstitutionEnabled(node: Node): boolean;
+
+        /**
+         * Determines whether before/after emit notifications should be raised in the pretty
+         * printer when it emits a node.
+         */
+        isEmitNotificationEnabled(node: Node): boolean;
+
+        /**
+         * Hook used by transformers to substitute expressions just before they
+         * are emitted by the pretty printer.
+         *
+         * @param node The node to substitute.
+         * @param isExpression A value indicating whether the node is in an expression context.
+         */
+        onSubstituteNode(node: Node, isExpression: boolean): Node;
+
+        /**
+         * Hook used to allow transformers to capture state before or after
+         * the printer emits a node.
+         *
+         * @param node The node to emit.
+         * @param emitCallback A callback used to emit the node.
+         */
+        onEmitNode(node: Node, emitCallback: (node: Node) => void): void;
+
+        /**
+         * Reset transient transformation properties on parse tree nodes.
+         */
+        dispose(): void;
+    }
+
+    export interface TransformationContext extends LexicalEnvironment {
+        getCompilerOptions(): CompilerOptions;
+        getEmitResolver(): EmitResolver;
+        getEmitHost(): EmitHost;
+
+        /**
+         * Gets flags used to customize later transformations or emit.
+         */
+        getNodeEmitFlags(node: Node): NodeEmitFlags;
+
+        /**
+         * Sets flags used to customize later transformations or emit.
+         */
+        setNodeEmitFlags<T extends Node>(node: T, flags: NodeEmitFlags): T;
+
+        /**
+         * Gets the TextRange to use for source maps for the node.
+         */
+        getSourceMapRange(node: Node): TextRange;
+
+        /**
+         * Sets the TextRange to use for source maps for the node.
+         */
+        setSourceMapRange<T extends Node>(node: T, range: TextRange): T;
+
+        /**
+         * Gets the TextRange to use for source maps for a token of a node.
+         */
+        getTokenSourceMapRange(node: Node, token: SyntaxKind): TextRange;
+
+        /**
+         * Sets the TextRange to use for source maps for a token of a node.
+         */
+        setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange): T;
+
+        /**
+         * Gets the TextRange to use for comments for the node.
+         */
+        getCommentRange(node: Node): TextRange;
+
+        /**
+         * Sets the TextRange to use for comments for the node.
+         */
+        setCommentRange<T extends Node>(node: T, range: TextRange): T;
+
+        /**
+         * Hoists a function declaration to the containing scope.
+         */
+        hoistFunctionDeclaration(node: FunctionDeclaration): void;
+
+        /**
+         * Hoists a variable declaration to the containing scope.
+         */
+        hoistVariableDeclaration(node: Identifier): void;
+
+        /**
+         * Enables expression substitutions in the pretty printer for the provided SyntaxKind.
+         */
+        enableSubstitution(kind: SyntaxKind): void;
+
+        /**
+         * Determines whether expression substitutions are enabled for the provided node.
+         */
+        isSubstitutionEnabled(node: Node): boolean;
+
+        /**
+         * Hook used by transformers to substitute expressions just before they
+         * are emitted by the pretty printer.
+         */
+        onSubstituteNode?: (node: Node, isExpression: boolean) => Node;
+
+        /**
+         * Enables before/after emit notifications in the pretty printer for the provided
+         * SyntaxKind.
+         */
+        enableEmitNotification(kind: SyntaxKind): void;
+
+        /**
+         * Determines whether before/after emit notifications should be raised in the pretty
+         * printer when it emits a node.
+         */
+        isEmitNotificationEnabled(node: Node): boolean;
+
+        /**
+         * Hook used to allow transformers to capture state before or after
+         * the printer emits a node.
+         */
+        onEmitNode?: (node: Node, emit: (node: Node) => void) => void;
+    }
+
+    /* @internal */
+    export type Transformer = (context: TransformationContext) => (node: SourceFile) => SourceFile;
+
+    export function getTransformers(compilerOptions: CompilerOptions) {
+        const jsx = compilerOptions.jsx;
+        const languageVersion = getEmitScriptTarget(compilerOptions);
+        const moduleKind = getEmitModuleKind(compilerOptions);
+        const transformers: Transformer[] = [];
+
+        transformers.push(transformTypeScript);
+        transformers.push(moduleTransformerMap[moduleKind] || moduleTransformerMap[ModuleKind.None]);
+
+        if (jsx === JsxEmit.React) {
+            transformers.push(transformJsx);
+        }
+
+        transformers.push(transformES7);
+
+        if (languageVersion < ScriptTarget.ES6) {
+            transformers.push(transformES6);
+            transformers.push(transformGenerators);
+        }
+
+        return transformers;
+    }
+
+    /**
+     * Tracks a monotonically increasing transformation id used to associate a node with a specific
+     * transformation. This ensures transient properties related to transformations can be safely
+     * stored on source tree nodes that may be reused across multiple transformations (such as
+     * with compile-on-save).
+     */
+    let nextTransformId = 1;
+
+    /**
+     * Transforms an array of SourceFiles by passing them through each transformer.
+     *
+     * @param resolver The emit resolver provided by the checker.
+     * @param host The emit host.
+     * @param sourceFiles An array of source files
+     * @param transforms An array of Transformers.
+     */
+    export function transformFiles(resolver: EmitResolver, host: EmitHost, sourceFiles: SourceFile[], transformers: Transformer[]): TransformationResult {
+        const transformId = nextTransformId;
+        nextTransformId++;
+
+        const tokenSourceMapRanges = createMap<TextRange>();
+        const lexicalEnvironmentVariableDeclarationsStack: VariableDeclaration[][] = [];
+        const lexicalEnvironmentFunctionDeclarationsStack: FunctionDeclaration[][] = [];
+        const enabledSyntaxKindFeatures = new Array<SyntaxKindFeatureFlags>(SyntaxKind.Count);
+        const parseTreeNodesWithAnnotations: Node[] = [];
+
+        let lastTokenSourceMapRangeNode: Node;
+        let lastTokenSourceMapRangeToken: SyntaxKind;
+        let lastTokenSourceMapRange: TextRange;
+        let lexicalEnvironmentStackOffset = 0;
+        let hoistedVariableDeclarations: VariableDeclaration[];
+        let hoistedFunctionDeclarations: FunctionDeclaration[];
+        let lexicalEnvironmentDisabled: boolean;
+
+        // The transformation context is provided to each transformer as part of transformer
+        // initialization.
+        const context: TransformationContext = {
+            getCompilerOptions: () => host.getCompilerOptions(),
+            getEmitResolver: () => resolver,
+            getEmitHost: () => host,
+            getNodeEmitFlags,
+            setNodeEmitFlags,
+            getSourceMapRange,
+            setSourceMapRange,
+            getTokenSourceMapRange,
+            setTokenSourceMapRange,
+            getCommentRange,
+            setCommentRange,
+            hoistVariableDeclaration,
+            hoistFunctionDeclaration,
+            startLexicalEnvironment,
+            endLexicalEnvironment,
+            onSubstituteNode,
+            enableSubstitution,
+            isSubstitutionEnabled,
+            onEmitNode,
+            enableEmitNotification,
+            isEmitNotificationEnabled
+        };
+
+        // Chain together and initialize each transformer.
+        const transformation = chain(...transformers)(context);
+
+        // Transform each source file.
+        const transformed = map(sourceFiles, transformSourceFile);
+
+        // Disable modification of the lexical environment.
+        lexicalEnvironmentDisabled = true;
+
+        return {
+            getSourceFiles: () => transformed,
+            getTokenSourceMapRange,
+            isSubstitutionEnabled,
+            isEmitNotificationEnabled,
+            onSubstituteNode: context.onSubstituteNode,
+            onEmitNode: context.onEmitNode,
+            dispose() {
+                // During transformation we may need to annotate a parse tree node with transient
+                // transformation properties. As parse tree nodes live longer than transformation
+                // nodes, we need to make sure we reclaim any memory allocated for custom ranges
+                // from these nodes to ensure we do not hold onto entire subtrees just for position
+                // information. We also need to reset these nodes to a pre-transformation state
+                // for incremental parsing scenarios so that we do not impact later emit.
+                for (const node of parseTreeNodesWithAnnotations) {
+                    if (node.transformId === transformId) {
+                        node.transformId = 0;
+                        node.emitFlags = 0;
+                        node.commentRange = undefined;
+                        node.sourceMapRange = undefined;
+                    }
+                }
+
+                parseTreeNodesWithAnnotations.length = 0;
+            }
+        };
+
+        /**
+         * Transforms a source file.
+         *
+         * @param sourceFile The source file to transform.
+         */
+        function transformSourceFile(sourceFile: SourceFile) {
+            if (isDeclarationFile(sourceFile)) {
+                return sourceFile;
+            }
+
+            return transformation(sourceFile);
+        }
+
+        /**
+         * Enables expression substitutions in the pretty printer for the provided SyntaxKind.
+         */
+        function enableSubstitution(kind: SyntaxKind) {
+            enabledSyntaxKindFeatures[kind] |= SyntaxKindFeatureFlags.Substitution;
+        }
+
+        /**
+         * Determines whether expression substitutions are enabled for the provided node.
+         */
+        function isSubstitutionEnabled(node: Node) {
+            return (enabledSyntaxKindFeatures[node.kind] & SyntaxKindFeatureFlags.Substitution) !== 0;
+        }
+
+        /**
+         * Default hook for node substitutions.
+         *
+         * @param node The node to substitute.
+         * @param isExpression A value indicating whether the node is to be used in an expression
+         *                     position.
+         */
+        function onSubstituteNode(node: Node, isExpression: boolean) {
+            return node;
+        }
+
+        /**
+         * Enables before/after emit notifications in the pretty printer for the provided SyntaxKind.
+         */
+        function enableEmitNotification(kind: SyntaxKind) {
+            enabledSyntaxKindFeatures[kind] |= SyntaxKindFeatureFlags.EmitNotifications;
+        }
+
+        /**
+         * Determines whether before/after emit notifications should be raised in the pretty
+         * printer when it emits a node.
+         */
+        function isEmitNotificationEnabled(node: Node) {
+            return (enabledSyntaxKindFeatures[node.kind] & SyntaxKindFeatureFlags.EmitNotifications) !== 0
+                || (getNodeEmitFlags(node) & NodeEmitFlags.AdviseOnEmitNode) !== 0;
+        }
+
+        /**
+         * Default hook for node emit.
+         *
+         * @param node The node to emit.
+         * @param emit A callback used to emit the node in the printer.
+         */
+        function onEmitNode(node: Node, emit: (node: Node) => void) {
+            emit(node);
+        }
+
+        /**
+         * Associates a node with the current transformation, initializing
+         * various transient transformation properties.
+         *
+         * @param node The node.
+         */
+        function beforeSetAnnotation(node: Node) {
+            if ((node.flags & NodeFlags.Synthesized) === 0 && node.transformId !== transformId) {
+                // To avoid holding onto transformation artifacts, we keep track of any
+                // parse tree node we are annotating. This allows us to clean them up after
+                // all transformations have completed.
+                parseTreeNodesWithAnnotations.push(node);
+                node.transformId = transformId;
+            }
+        }
+
+        /**
+         * Gets flags that control emit behavior of a node.
+         *
+         * If the node does not have its own NodeEmitFlags set, the node emit flags of its
+         * original pointer are used.
+         *
+         * @param node The node.
+         */
+        function getNodeEmitFlags(node: Node) {
+            return node.emitFlags;
+        }
+
+        /**
+         * Sets flags that control emit behavior of a node.
+         *
+         * @param node The node.
+         * @param emitFlags The NodeEmitFlags for the node.
+         */
+        function setNodeEmitFlags<T extends Node>(node: T, emitFlags: NodeEmitFlags) {
+            beforeSetAnnotation(node);
+            node.emitFlags = emitFlags;
+            return node;
+        }
+
+        /**
+         * Gets a custom text range to use when emitting source maps.
+         *
+         * If a node does not have its own custom source map text range, the custom source map
+         * text range of its original pointer is used.
+         *
+         * @param node The node.
+         */
+        function getSourceMapRange(node: Node) {
+            return node.sourceMapRange || node;
+        }
+
+        /**
+         * Sets a custom text range to use when emitting source maps.
+         *
+         * @param node The node.
+         * @param range The text range.
+         */
+        function setSourceMapRange<T extends Node>(node: T, range: TextRange) {
+            beforeSetAnnotation(node);
+            node.sourceMapRange = range;
+            return node;
+        }
+
+        /**
+         * Gets the TextRange to use for source maps for a token of a node.
+         *
+         * If a node does not have its own custom source map text range for a token, the custom
+         * source map text range for the token of its original pointer is used.
+         *
+         * @param node The node.
+         * @param token The token.
+         */
+        function getTokenSourceMapRange(node: Node, token: SyntaxKind) {
+            // As a performance optimization, use the cached value of the most recent node.
+            // This helps for cases where this function is called repeatedly for the same node.
+            if (lastTokenSourceMapRangeNode === node && lastTokenSourceMapRangeToken === token) {
+                return lastTokenSourceMapRange;
+            }
+
+            // Get the custom token source map range for a node or from one of its original nodes.
+            // Custom token ranges are not stored on the node to avoid the GC burden.
+            let range: TextRange;
+            let current = node;
+            while (current) {
+                range = current.id ? tokenSourceMapRanges[current.id + "-" + token] : undefined;
+                if (range !== undefined) {
+                    break;
+                }
+
+                current = current.original;
+            }
+
+            // Cache the most recently requested value.
+            lastTokenSourceMapRangeNode = node;
+            lastTokenSourceMapRangeToken = token;
+            lastTokenSourceMapRange = range;
+            return range;
+        }
+
+        /**
+         * Sets the TextRange to use for source maps for a token of a node.
+         *
+         * @param node The node.
+         * @param token The token.
+         * @param range The text range.
+         */
+        function setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: TextRange) {
+            // Cache the most recently requested value.
+            lastTokenSourceMapRangeNode = node;
+            lastTokenSourceMapRangeToken = token;
+            lastTokenSourceMapRange = range;
+            tokenSourceMapRanges[getNodeId(node) + "-" + token] = range;
+            return node;
+        }
+
+        /**
+         * Gets a custom text range to use when emitting comments.
+         *
+         * If a node does not have its own custom source map text range, the custom source map
+         * text range of its original pointer is used.
+         *
+         * @param node The node.
+         */
+        function getCommentRange(node: Node) {
+            return node.commentRange || node;
+        }
+
+        /**
+         * Sets a custom text range to use when emitting comments.
+         */
+        function setCommentRange<T extends Node>(node: T, range: TextRange) {
+            beforeSetAnnotation(node);
+            node.commentRange = range;
+            return node;
+        }
+
+        /**
+         * Records a hoisted variable declaration for the provided name within a lexical environment.
+         */
+        function hoistVariableDeclaration(name: Identifier): void {
+            Debug.assert(!lexicalEnvironmentDisabled, "Cannot modify the lexical environment during the print phase.");
+            const decl = createVariableDeclaration(name);
+            if (!hoistedVariableDeclarations) {
+                hoistedVariableDeclarations = [decl];
+            }
+            else {
+                hoistedVariableDeclarations.push(decl);
+            }
+        }
+
+        /**
+         * Records a hoisted function declaration within a lexical environment.
+         */
+        function hoistFunctionDeclaration(func: FunctionDeclaration): void {
+            Debug.assert(!lexicalEnvironmentDisabled, "Cannot modify the lexical environment during the print phase.");
+            if (!hoistedFunctionDeclarations) {
+                hoistedFunctionDeclarations = [func];
+            }
+            else {
+                hoistedFunctionDeclarations.push(func);
+            }
+        }
+
+        /**
+         * Starts a new lexical environment. Any existing hoisted variable or function declarations
+         * are pushed onto a stack, and the related storage variables are reset.
+         */
+        function startLexicalEnvironment(): void {
+            Debug.assert(!lexicalEnvironmentDisabled, "Cannot start a lexical environment during the print phase.");
+
+            // Save the current lexical environment. Rather than resizing the array we adjust the
+            // stack size variable. This allows us to reuse existing array slots we've
+            // already allocated between transformations to avoid allocation and GC overhead during
+            // transformation.
+            lexicalEnvironmentVariableDeclarationsStack[lexicalEnvironmentStackOffset] = hoistedVariableDeclarations;
+            lexicalEnvironmentFunctionDeclarationsStack[lexicalEnvironmentStackOffset] = hoistedFunctionDeclarations;
+            lexicalEnvironmentStackOffset++;
+            hoistedVariableDeclarations = undefined;
+            hoistedFunctionDeclarations = undefined;
+        }
+
+        /**
+         * Ends a lexical environment. The previous set of hoisted declarations are restored and
+         * any hoisted declarations added in this environment are returned.
+         */
+        function endLexicalEnvironment(): Statement[] {
+            Debug.assert(!lexicalEnvironmentDisabled, "Cannot end a lexical environment during the print phase.");
+
+            let statements: Statement[];
+            if (hoistedVariableDeclarations || hoistedFunctionDeclarations) {
+                if (hoistedFunctionDeclarations) {
+                    statements = [...hoistedFunctionDeclarations];
+                }
+
+                if (hoistedVariableDeclarations) {
+                    const statement = createVariableStatement(
+                        /*modifiers*/ undefined,
+                        createVariableDeclarationList(hoistedVariableDeclarations)
+                    );
+
+                    if (!statements) {
+                        statements = [statement];
+                    }
+                    else {
+                        statements.push(statement);
+                    }
+                }
+            }
+
+            // Restore the previous lexical environment.
+            lexicalEnvironmentStackOffset--;
+            hoistedVariableDeclarations = lexicalEnvironmentVariableDeclarationsStack[lexicalEnvironmentStackOffset];
+            hoistedFunctionDeclarations = lexicalEnvironmentFunctionDeclarationsStack[lexicalEnvironmentStackOffset];
+            return statements;
+        }
+    }
+
+    /**
+     * High-order function, creates a function that executes a function composition.
+     * For example, `chain(a, b)` is the equivalent of `x => ((a', b') => y => b'(a'(y)))(a(x), b(x))`
+     *
+     * @param args The functions to chain.
+     */
+    function chain<T, U>(...args: ((t: T) => (u: U) => U)[]): (t: T) => (u: U) => U;
+    function chain<T, U>(a: (t: T) => (u: U) => U, b: (t: T) => (u: U) => U, c: (t: T) => (u: U) => U, d: (t: T) => (u: U) => U, e: (t: T) => (u: U) => U): (t: T) => (u: U) => U {
+        if (e) {
+            const args: ((t: T) => (u: U) => U)[] = [];
+            for (let i = 0; i < arguments.length; i++) {
+                args[i] = arguments[i];
+            }
+
+            return t => compose(...map(args, f => f(t)));
+        }
+        else if (d) {
+            return t => compose(a(t), b(t), c(t), d(t));
+        }
+        else if (c) {
+            return t => compose(a(t), b(t), c(t));
+        }
+        else if (b) {
+            return t => compose(a(t), b(t));
+        }
+        else if (a) {
+            return t => compose(a(t));
+        }
+        else {
+            return t => u => u;
+        }
+    }
+
+    /**
+     * High-order function, composes functions. Note that functions are composed inside-out;
+     * for example, `compose(a, b)` is the equivalent of `x => b(a(x))`.
+     *
+     * @param args The functions to compose.
+     */
+    function compose<T>(...args: ((t: T) => T)[]): (t: T) => T;
+    function compose<T>(a: (t: T) => T, b: (t: T) => T, c: (t: T) => T, d: (t: T) => T, e: (t: T) => T): (t: T) => T {
+        if (e) {
+            const args: ((t: T) => T)[] = [];
+            for (let i = 0; i < arguments.length; i++) {
+                args[i] = arguments[i];
+            }
+
+            return t => reduceLeft<(t: T) => T, T>(args, (u, f) => f(u), t);
+        }
+        else if (d) {
+            return t => d(c(b(a(t))));
+        }
+        else if (c) {
+            return t => c(b(a(t)));
+        }
+        else if (b) {
+            return t => b(a(t));
+        }
+        else if (a) {
+            return t => a(t);
+        }
+        else {
+            return t => t;
+        }
+    }
+}

src/compiler/transformers/destructuring.ts

@@ -0,0 +1,423 @@
+/// <reference path="../factory.ts" />
+/// <reference path="../visitor.ts" />
+
+/*@internal*/
+namespace ts {
+    /**
+     * Flattens a destructuring assignment expression.
+     *
+     * @param root The destructuring assignment expression.
+     * @param needsValue Indicates whether the value from the right-hand-side of the
+     *                   destructuring assignment is needed as part of a larger expression.
+     * @param recordTempVariable A callback used to record new temporary variables.
+     * @param visitor An optional visitor to use to visit expressions.
+     */
+    export function flattenDestructuringAssignment(
+        context: TransformationContext,
+        node: BinaryExpression,
+        needsValue: boolean,
+        recordTempVariable: (node: Identifier) => void,
+        visitor?: (node: Node) => VisitResult<Node>): Expression {
+
+        if (isEmptyObjectLiteralOrArrayLiteral(node.left)) {
+            const right = node.right;
+            if (isDestructuringAssignment(right)) {
+                return flattenDestructuringAssignment(context, right, needsValue, recordTempVariable, visitor);
+            }
+            else {
+                return node.right;
+            }
+        }
+
+        let location: TextRange = node;
+        let value = node.right;
+        const expressions: Expression[] = [];
+        if (needsValue) {
+            // If the right-hand value of the destructuring assignment needs to be preserved (as
+            // is the case when the destructuring assignmen) is part of a larger expression),
+            // then we need to cache the right-hand value.
+            //
+            // The source map location for the assignment should point to the entire binary
+            // expression.
+            value = ensureIdentifier(value, /*reuseIdentifierExpressions*/ true, location, emitTempVariableAssignment, visitor);
+        }
+        else if (nodeIsSynthesized(node)) {
+            // Generally, the source map location for a destructuring assignment is the root
+            // expression.
+            //
+            // However, if the root expression is synthesized (as in the case
+            // of the initializer when transforming a ForOfStatement), then the source map
+            // location should point to the right-hand value of the expression.
+            location = value;
+        }
+
+        flattenDestructuring(context, node, value, location, emitAssignment, emitTempVariableAssignment, visitor);
+
+        if (needsValue) {
+            expressions.push(value);
+        }
+
+        const expression = inlineExpressions(expressions);
+        aggregateTransformFlags(expression);
+        return expression;
+
+        function emitAssignment(name: Identifier, value: Expression, location: TextRange) {
+            const expression = createAssignment(name, value, location);
+
+            // NOTE: this completely disables source maps, but aligns with the behavior of
+            //       `emitAssignment` in the old emitter.
+            context.setNodeEmitFlags(expression, NodeEmitFlags.NoNestedSourceMaps);
+
+            aggregateTransformFlags(expression);
+            expressions.push(expression);
+        }
+
+        function emitTempVariableAssignment(value: Expression, location: TextRange) {
+            const name = createTempVariable(recordTempVariable);
+            emitAssignment(name, value, location);
+            return name;
+        }
+    }
+
+    /**
+     * Flattens binding patterns in a parameter declaration.
+     *
+     * @param node The ParameterDeclaration to flatten.
+     * @param value The rhs value for the binding pattern.
+     * @param visitor An optional visitor to use to visit expressions.
+     */
+    export function flattenParameterDestructuring(
+        context: TransformationContext,
+        node: ParameterDeclaration,
+        value: Expression,
+        visitor?: (node: Node) => VisitResult<Node>) {
+        const declarations: VariableDeclaration[] = [];
+
+        flattenDestructuring(context, node, value, node, emitAssignment, emitTempVariableAssignment, visitor);
+
+        return declarations;
+
+        function emitAssignment(name: Identifier, value: Expression, location: TextRange) {
+            const declaration = createVariableDeclaration(name, /*type*/ undefined, value, location);
+
+            // NOTE: this completely disables source maps, but aligns with the behavior of
+            //       `emitAssignment` in the old emitter.
+            context.setNodeEmitFlags(declaration, NodeEmitFlags.NoNestedSourceMaps);
+
+            aggregateTransformFlags(declaration);
+            declarations.push(declaration);
+        }
+
+        function emitTempVariableAssignment(value: Expression, location: TextRange) {
+            const name = createTempVariable(/*recordTempVariable*/ undefined);
+            emitAssignment(name, value, location);
+            return name;
+        }
+    }
+
+    /**
+     * Flattens binding patterns in a variable declaration.
+     *
+     * @param node The VariableDeclaration to flatten.
+     * @param value An optional rhs value for the binding pattern.
+     * @param visitor An optional visitor to use to visit expressions.
+     */
+    export function flattenVariableDestructuring(
+        context: TransformationContext,
+        node: VariableDeclaration,
+        value?: Expression,
+        visitor?: (node: Node) => VisitResult<Node>) {
+        const declarations: VariableDeclaration[] = [];
+
+        flattenDestructuring(context, node, value, node, emitAssignment, emitTempVariableAssignment, visitor);
+
+        return declarations;
+
+        function emitAssignment(name: Identifier, value: Expression, location: TextRange, original: Node) {
+            const declaration = createVariableDeclaration(name, /*type*/ undefined, value, location);
+            declaration.original = original;
+
+            // NOTE: this completely disables source maps, but aligns with the behavior of
+            //       `emitAssignment` in the old emitter.
+            context.setNodeEmitFlags(declaration, NodeEmitFlags.NoNestedSourceMaps);
+
+            declarations.push(declaration);
+            aggregateTransformFlags(declaration);
+        }
+
+        function emitTempVariableAssignment(value: Expression, location: TextRange) {
+            const name = createTempVariable(/*recordTempVariable*/ undefined);
+            emitAssignment(name, value, location, /*original*/ undefined);
+            return name;
+        }
+    }
+
+    /**
+     * Flattens binding patterns in a variable declaration and transforms them into an expression.
+     *
+     * @param node The VariableDeclaration to flatten.
+     * @param recordTempVariable A callback used to record new temporary variables.
+     * @param nameSubstitution An optional callback used to substitute binding names.
+     * @param visitor An optional visitor to use to visit expressions.
+     */
+    export function flattenVariableDestructuringToExpression(
+        context: TransformationContext,
+        node: VariableDeclaration,
+        recordTempVariable: (name: Identifier) => void,
+        nameSubstitution?: (name: Identifier) => Expression,
+        visitor?: (node: Node) => VisitResult<Node>) {
+
+        const pendingAssignments: Expression[] = [];
+
+        flattenDestructuring(context, node, /*value*/ undefined, node, emitAssignment, emitTempVariableAssignment, visitor);
+
+        const expression = inlineExpressions(pendingAssignments);
+        aggregateTransformFlags(expression);
+        return expression;
+
+        function emitAssignment(name: Identifier, value: Expression, location: TextRange, original: Node) {
+            const left = nameSubstitution && nameSubstitution(name) || name;
+            emitPendingAssignment(left, value, location, original);
+        }
+
+        function emitTempVariableAssignment(value: Expression, location: TextRange) {
+            const name = createTempVariable(recordTempVariable);
+            emitPendingAssignment(name, value, location, /*original*/ undefined);
+            return name;
+        }
+
+        function emitPendingAssignment(name: Expression, value: Expression, location: TextRange, original: Node) {
+            const expression = createAssignment(name, value, location);
+            expression.original = original;
+
+            // NOTE: this completely disables source maps, but aligns with the behavior of
+            //       `emitAssignment` in the old emitter.
+            context.setNodeEmitFlags(expression, NodeEmitFlags.NoNestedSourceMaps);
+
+            pendingAssignments.push(expression);
+            return expression;
+        }
+    }
+
+    function flattenDestructuring(
+        context: TransformationContext,
+        root: BindingElement | BinaryExpression,
+        value: Expression,
+        location: TextRange,
+        emitAssignment: (name: Identifier, value: Expression, location: TextRange, original: Node) => void,
+        emitTempVariableAssignment: (value: Expression, location: TextRange) => Identifier,
+        visitor?: (node: Node) => VisitResult<Node>) {
+        if (value && visitor) {
+            value = visitNode(value, visitor, isExpression);
+        }
+
+        if (isBinaryExpression(root)) {
+            emitDestructuringAssignment(root.left, value, location);
+        }
+        else {
+            emitBindingElement(root, value);
+        }
+
+        function emitDestructuringAssignment(bindingTarget: Expression | ShorthandPropertyAssignment, value: Expression, location: TextRange) {
+            // When emitting target = value use source map node to highlight, including any temporary assignments needed for this
+            let target: Expression;
+            if (isShorthandPropertyAssignment(bindingTarget)) {
+                const initializer = visitor
+                    ? visitNode(bindingTarget.objectAssignmentInitializer, visitor, isExpression)
+                    : bindingTarget.objectAssignmentInitializer;
+
+                if (initializer) {
+                    value = createDefaultValueCheck(value, initializer, location);
+                }
+
+                target = bindingTarget.name;
+            }
+            else if (isBinaryExpression(bindingTarget) && bindingTarget.operatorToken.kind === SyntaxKind.EqualsToken) {
+                const initializer = visitor
+                    ? visitNode(bindingTarget.right, visitor, isExpression)
+                    : bindingTarget.right;
+
+                value = createDefaultValueCheck(value, initializer, location);
+                target = bindingTarget.left;
+            }
+            else {
+                target = bindingTarget;
+            }
+
+            if (target.kind === SyntaxKind.ObjectLiteralExpression) {
+                emitObjectLiteralAssignment(<ObjectLiteralExpression>target, value, location);
+            }
+            else if (target.kind === SyntaxKind.ArrayLiteralExpression) {
+                emitArrayLiteralAssignment(<ArrayLiteralExpression>target, value, location);
+            }
+            else {
+                const name = getMutableClone(<Identifier>target);
+                context.setSourceMapRange(name, target);
+                context.setCommentRange(name, target);
+                emitAssignment(name, value, location, /*original*/ undefined);
+            }
+        }
+
+        function emitObjectLiteralAssignment(target: ObjectLiteralExpression, value: Expression, location: TextRange) {
+            const properties = target.properties;
+            if (properties.length !== 1) {
+                // For anything but a single element destructuring we need to generate a temporary
+                // to ensure value is evaluated exactly once.
+                // When doing so we want to hightlight the passed in source map node since thats the one needing this temp assignment
+                value = ensureIdentifier(value, /*reuseIdentifierExpressions*/ true, location, emitTempVariableAssignment);
+            }
+
+            for (const p of properties) {
+                if (p.kind === SyntaxKind.PropertyAssignment || p.kind === SyntaxKind.ShorthandPropertyAssignment) {
+                    const propName = <Identifier | LiteralExpression>(<PropertyAssignment>p).name;
+                    const target = p.kind === SyntaxKind.ShorthandPropertyAssignment ? <ShorthandPropertyAssignment>p : (<PropertyAssignment>p).initializer || propName;
+                    // Assignment for target = value.propName should highligh whole property, hence use p as source map node
+                    emitDestructuringAssignment(target, createDestructuringPropertyAccess(value, propName), p);
+                }
+            }
+        }
+
+        function emitArrayLiteralAssignment(target: ArrayLiteralExpression, value: Expression, location: TextRange) {
+            const elements = target.elements;
+            const numElements = elements.length;
+            if (numElements !== 1) {
+                // For anything but a single element destructuring we need to generate a temporary
+                // to ensure value is evaluated exactly once.
+                // When doing so we want to hightlight the passed in source map node since thats the one needing this temp assignment
+                value = ensureIdentifier(value, /*reuseIdentifierExpressions*/ true, location, emitTempVariableAssignment);
+            }
+
+            for (let i = 0; i < numElements; i++) {
+                const e = elements[i];
+                if (e.kind !== SyntaxKind.OmittedExpression) {
+                    // Assignment for target = value.propName should highligh whole property, hence use e as source map node
+                    if (e.kind !== SyntaxKind.SpreadElementExpression) {
+                        emitDestructuringAssignment(e, createElementAccess(value, createLiteral(i)), e);
+                    }
+                    else if (i === numElements - 1) {
+                        emitDestructuringAssignment((<SpreadElementExpression>e).expression, createArraySlice(value, i), e);
+                    }
+                }
+            }
+        }
+
+        function emitBindingElement(target: BindingElement, value: Expression) {
+            // Any temporary assignments needed to emit target = value should point to target
+            const initializer = visitor ? visitNode(target.initializer, visitor, isExpression) : target.initializer;
+            if (initializer) {
+                // Combine value and initializer
+                value = value ? createDefaultValueCheck(value, initializer, target) : initializer;
+            }
+            else if (!value) {
+                // Use 'void 0' in absence of value and initializer
+                value = createVoidZero();
+            }
+
+            const name = target.name;
+            if (isBindingPattern(name)) {
+                const elements = name.elements;
+                const numElements = elements.length;
+                if (numElements !== 1) {
+                    // For anything other than a single-element destructuring we need to generate a temporary
+                    // to ensure value is evaluated exactly once. Additionally, if we have zero elements
+                    // we need to emit *something* to ensure that in case a 'var' keyword was already emitted,
+                    // so in that case, we'll intentionally create that temporary.
+                    value = ensureIdentifier(value, /*reuseIdentifierExpressions*/ numElements !== 0, target, emitTempVariableAssignment);
+                }
+                for (let i = 0; i < numElements; i++) {
+                    const element = elements[i];
+                    if (name.kind === SyntaxKind.ObjectBindingPattern) {
+                        // Rewrite element to a declaration with an initializer that fetches property
+                        const propName = element.propertyName || <Identifier>element.name;
+                        emitBindingElement(element, createDestructuringPropertyAccess(value, propName));
+                    }
+                    else if (element.kind !== SyntaxKind.OmittedExpression) {
+                        if (!element.dotDotDotToken) {
+                            // Rewrite element to a declaration that accesses array element at index i
+                            emitBindingElement(element, createElementAccess(value, i));
+                        }
+                        else if (i === numElements - 1) {
+                            emitBindingElement(element, createArraySlice(value, i));
+                        }
+                    }
+                }
+            }
+            else {
+                emitAssignment(name, value, target, target);
+            }
+        }
+
+        function createDefaultValueCheck(value: Expression, defaultValue: Expression, location: TextRange): Expression {
+            value = ensureIdentifier(value, /*reuseIdentifierExpressions*/ true, location, emitTempVariableAssignment);
+            return createConditional(
+                createStrictEquality(value, createVoidZero()),
+                createToken(SyntaxKind.QuestionToken),
+                defaultValue,
+                createToken(SyntaxKind.ColonToken),
+                value
+            );
+        }
+
+        /**
+         * Creates either a PropertyAccessExpression or an ElementAccessExpression for the
+         * right-hand side of a transformed destructuring assignment.
+         *
+         * @param expression The right-hand expression that is the source of the property.
+         * @param propertyName The destructuring property name.
+         */
+        function createDestructuringPropertyAccess(expression: Expression, propertyName: PropertyName): LeftHandSideExpression {
+            if (isComputedPropertyName(propertyName)) {
+                return createElementAccess(
+                    expression,
+                    ensureIdentifier(propertyName.expression, /*reuseIdentifierExpressions*/ false, /*location*/ propertyName, emitTempVariableAssignment)
+                );
+            }
+            else if (isLiteralExpression(propertyName)) {
+                const clone = getSynthesizedClone(propertyName);
+                clone.text = unescapeIdentifier(clone.text);
+                return createElementAccess(expression, clone);
+            }
+            else {
+                if (isGeneratedIdentifier(propertyName)) {
+                    const clone = getSynthesizedClone(propertyName);
+                    clone.text = unescapeIdentifier(clone.text);
+                    return createPropertyAccess(expression, clone);
+                }
+                else {
+                    return createPropertyAccess(expression, createIdentifier(unescapeIdentifier(propertyName.text)));
+                }
+            }
+        }
+    }
+
+    /**
+     * Ensures that there exists a declared identifier whose value holds the given expression.
+     * This function is useful to ensure that the expression's value can be read from in subsequent expressions.
+     * Unless 'reuseIdentifierExpressions' is false, 'value' will be returned if it is just an identifier.
+     *
+     * @param value the expression whose value needs to be bound.
+     * @param reuseIdentifierExpressions true if identifier expressions can simply be returned;
+     *                                   false if it is necessary to always emit an identifier.
+     * @param location The location to use for source maps and comments.
+     * @param emitTempVariableAssignment A callback used to emit a temporary variable.
+     * @param visitor An optional callback used to visit the value.
+     */
+    function ensureIdentifier(
+        value: Expression,
+        reuseIdentifierExpressions: boolean,
+        location: TextRange,
+        emitTempVariableAssignment: (value: Expression, location: TextRange) => Identifier,
+        visitor?: (node: Node) => VisitResult<Node>) {
+
+        if (isIdentifier(value) && reuseIdentifierExpressions) {
+            return value;
+        }
+        else {
+            if (visitor) {
+                value = visitNode(value, visitor, isExpression);
+            }
+
+            return emitTempVariableAssignment(value, location);
+        }
+    }
+}

src/compiler/transformers/es7.ts

@@ -0,0 +1,97 @@
+/// <reference path="../factory.ts" />
+/// <reference path="../visitor.ts" />
+
+/*@internal*/
+namespace ts {
+    export function transformES7(context: TransformationContext) {
+        const { hoistVariableDeclaration } = context;
+
+        return transformSourceFile;
+
+        function transformSourceFile(node: SourceFile) {
+            return visitEachChild(node, visitor, context);
+        }
+
+        function visitor(node: Node): VisitResult<Node> {
+            if (node.transformFlags & TransformFlags.ES7) {
+                return visitorWorker(node);
+            }
+            else if (node.transformFlags & TransformFlags.ContainsES7) {
+                return visitEachChild(node, visitor, context);
+            }
+            else {
+                return node;
+            }
+        }
+
+        function visitorWorker(node: Node): VisitResult<Node> {
+            switch (node.kind) {
+                case SyntaxKind.BinaryExpression:
+                    return visitBinaryExpression(<BinaryExpression>node);
+
+                default:
+                    Debug.failBadSyntaxKind(node);
+                    return visitEachChild(node, visitor, context);
+            }
+        }
+
+        function visitBinaryExpression(node: BinaryExpression): Expression {
+            // We are here because ES7 adds support for the exponentiation operator.
+            const left = visitNode(node.left, visitor, isExpression);
+            const right = visitNode(node.right, visitor, isExpression);
+            if (node.operatorToken.kind === SyntaxKind.AsteriskAsteriskEqualsToken) {
+                let target: Expression;
+                let value: Expression;
+                if (isElementAccessExpression(left)) {
+                    // Transforms `a[x] **= b` into `(_a = a)[_x = x] = Math.pow(_a[_x], b)`
+                    const expressionTemp = createTempVariable(hoistVariableDeclaration);
+
+                    const argumentExpressionTemp = createTempVariable(hoistVariableDeclaration);
+
+                    target = createElementAccess(
+                        createAssignment(expressionTemp, left.expression, /*location*/ left.expression),
+                        createAssignment(argumentExpressionTemp, left.argumentExpression, /*location*/ left.argumentExpression),
+                        /*location*/ left
+                    );
+
+                    value = createElementAccess(
+                        expressionTemp,
+                        argumentExpressionTemp,
+                        /*location*/ left
+                    );
+                }
+                else if (isPropertyAccessExpression(left)) {
+                    // Transforms `a.x **= b` into `(_a = a).x = Math.pow(_a.x, b)`
+                    const expressionTemp = createTempVariable(hoistVariableDeclaration);
+
+                    target = createPropertyAccess(
+                        createAssignment(expressionTemp, left.expression, /*location*/ left.expression),
+                        left.name,
+                        /*location*/ left
+                    );
+
+                    value = createPropertyAccess(
+                        expressionTemp,
+                        left.name,
+                        /*location*/ left
+                    );
+                }
+                else {
+                    // Transforms `a **= b` into `a = Math.pow(a, b)`
+                    target = left;
+                    value = left;
+                }
+
+                return createAssignment(target, createMathPow(value, right, /*location*/ node), /*location*/ node);
+            }
+            else if (node.operatorToken.kind === SyntaxKind.AsteriskAsteriskToken) {
+                // Transforms `a ** b` into `Math.pow(a, b)`
+                return createMathPow(left, right, /*location*/ node);
+            }
+            else {
+                Debug.failBadSyntaxKind(node);
+                return visitEachChild(node, visitor, context);
+            }
+        }
+    }
+}

src/compiler/transformers/jsx.ts

@@ -0,0 +1,518 @@
+/// <reference path="../factory.ts" />
+/// <reference path="../visitor.ts" />
+
+/*@internal*/
+namespace ts {
+    const entities: Map<number> = createEntitiesMap();
+
+    export function transformJsx(context: TransformationContext) {
+        const compilerOptions = context.getCompilerOptions();
+        let currentSourceFile: SourceFile;
+        return transformSourceFile;
+
+        /**
+         * Transform JSX-specific syntax in a SourceFile.
+         *
+         * @param node A SourceFile node.
+         */
+        function transformSourceFile(node: SourceFile) {
+            currentSourceFile = node;
+            node = visitEachChild(node, visitor, context);
+            currentSourceFile = undefined;
+            return node;
+        }
+
+        function visitor(node: Node): VisitResult<Node> {
+            if (node.transformFlags & TransformFlags.Jsx) {
+                return visitorWorker(node);
+            }
+            else if (node.transformFlags & TransformFlags.ContainsJsx) {
+                return visitEachChild(node, visitor, context);
+            }
+            else {
+                return node;
+            }
+        }
+
+        function visitorWorker(node: Node): VisitResult<Node> {
+            switch (node.kind) {
+                case SyntaxKind.JsxElement:
+                    return visitJsxElement(<JsxElement>node, /*isChild*/ false);
+
+                case SyntaxKind.JsxSelfClosingElement:
+                    return visitJsxSelfClosingElement(<JsxSelfClosingElement>node, /*isChild*/ false);
+
+                case SyntaxKind.JsxExpression:
+                    return visitJsxExpression(<JsxExpression>node);
+
+                default:
+                    Debug.failBadSyntaxKind(node);
+                    return undefined;
+            }
+        }
+
+        function transformJsxChildToExpression(node: JsxChild): Expression {
+            switch (node.kind) {
+                case SyntaxKind.JsxText:
+                    return visitJsxText(<JsxText>node);
+
+                case SyntaxKind.JsxExpression:
+                    return visitJsxExpression(<JsxExpression>node);
+
+                case SyntaxKind.JsxElement:
+                    return visitJsxElement(<JsxElement>node, /*isChild*/ true);
+
+                case SyntaxKind.JsxSelfClosingElement:
+                    return visitJsxSelfClosingElement(<JsxSelfClosingElement>node, /*isChild*/ true);
+
+                default:
+                    Debug.failBadSyntaxKind(node);
+                    return undefined;
+            }
+        }
+
+        function visitJsxElement(node: JsxElement, isChild: boolean) {
+            return visitJsxOpeningLikeElement(node.openingElement, node.children, isChild, /*location*/ node);
+        }
+
+        function visitJsxSelfClosingElement(node: JsxSelfClosingElement, isChild: boolean) {
+            return visitJsxOpeningLikeElement(node, /*children*/ undefined, isChild, /*location*/ node);
+        }
+
+        function visitJsxOpeningLikeElement(node: JsxOpeningLikeElement, children: JsxChild[], isChild: boolean, location: TextRange) {
+            const tagName = getTagName(node);
+            let objectProperties: Expression;
+            const attrs = node.attributes;
+            if (attrs.length === 0) {
+                // When there are no attributes, React wants "null"
+                objectProperties = createNull();
+            }
+            else {
+                // Map spans of JsxAttribute nodes into object literals and spans
+                // of JsxSpreadAttribute nodes into expressions.
+                const segments = flatten(
+                    spanMap(attrs, isJsxSpreadAttribute, (attrs, isSpread) => isSpread
+                        ? map(attrs, transformJsxSpreadAttributeToExpression)
+                        : createObjectLiteral(map(attrs, transformJsxAttributeToObjectLiteralElement))
+                    )
+                );
+
+                if (isJsxSpreadAttribute(attrs[0])) {
+                    // We must always emit at least one object literal before a spread
+                    // argument.
+                    segments.unshift(createObjectLiteral());
+                }
+
+                // Either emit one big object literal (no spread attribs), or
+                // a call to the __assign helper.
+                objectProperties = singleOrUndefined(segments)
+                    || createAssignHelper(currentSourceFile.externalHelpersModuleName, segments);
+            }
+
+            const element = createReactCreateElement(
+                compilerOptions.reactNamespace,
+                tagName,
+                objectProperties,
+                filter(map(children, transformJsxChildToExpression), isDefined),
+                node,
+                location
+            );
+
+            if (isChild) {
+                startOnNewLine(element);
+            }
+
+            return element;
+        }
+
+        function transformJsxSpreadAttributeToExpression(node: JsxSpreadAttribute) {
+            return visitNode(node.expression, visitor, isExpression);
+        }
+
+        function transformJsxAttributeToObjectLiteralElement(node: JsxAttribute) {
+            const name = getAttributeName(node);
+            const expression = transformJsxAttributeInitializer(node.initializer);
+            return createPropertyAssignment(name, expression);
+        }
+
+        function transformJsxAttributeInitializer(node: StringLiteral | JsxExpression) {
+            if (node === undefined) {
+                return createLiteral(true);
+            }
+            else if (node.kind === SyntaxKind.StringLiteral) {
+                return node;
+            }
+            else if (node.kind === SyntaxKind.JsxExpression) {
+                return visitJsxExpression(<JsxExpression>node);
+            }
+            else {
+                Debug.failBadSyntaxKind(node);
+            }
+        }
+
+        function visitJsxText(node: JsxText) {
+            const text = getTextOfNode(node, /*includeTrivia*/ true);
+            let parts: Expression[];
+            let firstNonWhitespace = 0;
+            let lastNonWhitespace = -1;
+
+            // JSX trims whitespace at the end and beginning of lines, except that the
+            // start/end of a tag is considered a start/end of a line only if that line is
+            // on the same line as the closing tag. See examples in
+            // tests/cases/conformance/jsx/tsxReactEmitWhitespace.tsx
+            for (let i = 0; i < text.length; i++) {
+                const c = text.charCodeAt(i);
+                if (isLineBreak(c)) {
+                    if (firstNonWhitespace !== -1 && (lastNonWhitespace - firstNonWhitespace + 1 > 0)) {
+                        const part = text.substr(firstNonWhitespace, lastNonWhitespace - firstNonWhitespace + 1);
+                        if (!parts) {
+                            parts = [];
+                        }
+
+                        // We do not escape the string here as that is handled by the printer
+                        // when it emits the literal. We do, however, need to decode JSX entities.
+                        parts.push(createLiteral(decodeEntities(part)));
+                    }
+
+                    firstNonWhitespace = -1;
+                }
+                else if (!isWhiteSpace(c)) {
+                    lastNonWhitespace = i;
+                    if (firstNonWhitespace === -1) {
+                        firstNonWhitespace = i;
+                    }
+                }
+            }
+
+            if (firstNonWhitespace !== -1) {
+                const part = text.substr(firstNonWhitespace);
+                if (!parts) {
+                    parts = [];
+                }
+
+                // We do not escape the string here as that is handled by the printer
+                // when it emits the literal. We do, however, need to decode JSX entities.
+                parts.push(createLiteral(decodeEntities(part)));
+            }
+
+            if (parts) {
+                return reduceLeft(parts, aggregateJsxTextParts);
+            }
+
+            return undefined;
+        }
+
+        /**
+         * Aggregates two expressions by interpolating them with a whitespace literal.
+         */
+        function aggregateJsxTextParts(left: Expression, right: Expression) {
+            return createAdd(createAdd(left, createLiteral(" ")), right);
+        }
+
+        /**
+         * Decodes JSX entities.
+         */
+        function decodeEntities(text: string) {
+            return text.replace(/&(\w+);/g, function(s: any, m: string) {
+                if (entities[m] !== undefined) {
+                    return String.fromCharCode(entities[m]);
+                }
+                else {
+                    return s;
+                }
+            });
+        }
+
+        function getTagName(node: JsxElement | JsxOpeningLikeElement): Expression {
+            if (node.kind === SyntaxKind.JsxElement) {
+                return getTagName((<JsxElement>node).openingElement);
+            }
+            else {
+                const name = (<JsxOpeningLikeElement>node).tagName;
+                if (isIdentifier(name) && isIntrinsicJsxName(name.text)) {
+                    return createLiteral(name.text);
+                }
+                else {
+                    return createExpressionFromEntityName(name);
+                }
+            }
+        }
+
+        /**
+         * Emit an attribute name, which is quoted if it needs to be quoted. Because
+         * these emit into an object literal property name, we don't need to be worried
+         * about keywords, just non-identifier characters
+         */
+        function getAttributeName(node: JsxAttribute): StringLiteral | Identifier {
+            const name = node.name;
+            if (/^[A-Za-z_]\w*$/.test(name.text)) {
+                return name;
+            }
+            else {
+                return createLiteral(name.text);
+            }
+        }
+
+        function visitJsxExpression(node: JsxExpression) {
+            return visitNode(node.expression, visitor, isExpression);
+        }
+    }
+
+    function createEntitiesMap(): Map<number> {
+        return createMap<number>({
+            "quot": 0x0022,
+            "amp": 0x0026,
+            "apos": 0x0027,
+            "lt": 0x003C,
+            "gt": 0x003E,
+            "nbsp": 0x00A0,
+            "iexcl": 0x00A1,
+            "cent": 0x00A2,
+            "pound": 0x00A3,
+            "curren": 0x00A4,
+            "yen": 0x00A5,
+            "brvbar": 0x00A6,
+            "sect": 0x00A7,
+            "uml": 0x00A8,
+            "copy": 0x00A9,
+            "ordf": 0x00AA,
+            "laquo": 0x00AB,
+            "not": 0x00AC,
+            "shy": 0x00AD,
+            "reg": 0x00AE,
+            "macr": 0x00AF,
+            "deg": 0x00B0,
+            "plusmn": 0x00B1,
+            "sup2": 0x00B2,
+            "sup3": 0x00B3,
+            "acute": 0x00B4,
+            "micro": 0x00B5,
+            "para": 0x00B6,
+            "middot": 0x00B7,
+            "cedil": 0x00B8,
+            "sup1": 0x00B9,
+            "ordm": 0x00BA,
+            "raquo": 0x00BB,
+            "frac14": 0x00BC,
+            "frac12": 0x00BD,
+            "frac34": 0x00BE,
+            "iquest": 0x00BF,
+            "Agrave": 0x00C0,
+            "Aacute": 0x00C1,
+            "Acirc": 0x00C2,
+            "Atilde": 0x00C3,
+            "Auml": 0x00C4,
+            "Aring": 0x00C5,
+            "AElig": 0x00C6,
+            "Ccedil": 0x00C7,
+            "Egrave": 0x00C8,
+            "Eacute": 0x00C9,
+            "Ecirc": 0x00CA,
+            "Euml": 0x00CB,
+            "Igrave": 0x00CC,
+            "Iacute": 0x00CD,
+            "Icirc": 0x00CE,
+            "Iuml": 0x00CF,
+            "ETH": 0x00D0,
+            "Ntilde": 0x00D1,
+            "Ograve": 0x00D2,
+            "Oacute": 0x00D3,
+            "Ocirc": 0x00D4,
+            "Otilde": 0x00D5,
+            "Ouml": 0x00D6,
+            "times": 0x00D7,
+            "Oslash": 0x00D8,
+            "Ugrave": 0x00D9,
+            "Uacute": 0x00DA,
+            "Ucirc": 0x00DB,
+            "Uuml": 0x00DC,
+            "Yacute": 0x00DD,
+            "THORN": 0x00DE,
+            "szlig": 0x00DF,
+            "agrave": 0x00E0,
+            "aacute": 0x00E1,
+            "acirc": 0x00E2,
+            "atilde": 0x00E3,
+            "auml": 0x00E4,
+            "aring": 0x00E5,
+            "aelig": 0x00E6,
+            "ccedil": 0x00E7,
+            "egrave": 0x00E8,
+            "eacute": 0x00E9,
+            "ecirc": 0x00EA,
+            "euml": 0x00EB,
+            "igrave": 0x00EC,
+            "iacute": 0x00ED,
+            "icirc": 0x00EE,
+            "iuml": 0x00EF,
+            "eth": 0x00F0,
+            "ntilde": 0x00F1,
+            "ograve": 0x00F2,
+            "oacute": 0x00F3,
+            "ocirc": 0x00F4,
+            "otilde": 0x00F5,
+            "ouml": 0x00F6,
+            "divide": 0x00F7,
+            "oslash": 0x00F8,
+            "ugrave": 0x00F9,
+            "uacute": 0x00FA,
+            "ucirc": 0x00FB,
+            "uuml": 0x00FC,
+            "yacute": 0x00FD,
+            "thorn": 0x00FE,
+            "yuml": 0x00FF,
+            "OElig": 0x0152,
+            "oelig": 0x0153,
+            "Scaron": 0x0160,
+            "scaron": 0x0161,
+            "Yuml": 0x0178,
+            "fnof": 0x0192,
+            "circ": 0x02C6,
+            "tilde": 0x02DC,
+            "Alpha": 0x0391,
+            "Beta": 0x0392,
+            "Gamma": 0x0393,
+            "Delta": 0x0394,
+            "Epsilon": 0x0395,
+            "Zeta": 0x0396,
+            "Eta": 0x0397,
+            "Theta": 0x0398,
+            "Iota": 0x0399,
+            "Kappa": 0x039A,
+            "Lambda": 0x039B,
+            "Mu": 0x039C,
+            "Nu": 0x039D,
+            "Xi": 0x039E,
+            "Omicron": 0x039F,
+            "Pi": 0x03A0,
+            "Rho": 0x03A1,
+            "Sigma": 0x03A3,
+            "Tau": 0x03A4,
+            "Upsilon": 0x03A5,
+            "Phi": 0x03A6,
+            "Chi": 0x03A7,
+            "Psi": 0x03A8,
+            "Omega": 0x03A9,
+            "alpha": 0x03B1,
+            "beta": 0x03B2,
+            "gamma": 0x03B3,
+            "delta": 0x03B4,
+            "epsilon": 0x03B5,
+            "zeta": 0x03B6,
+            "eta": 0x03B7,
+            "theta": 0x03B8,
+            "iota": 0x03B9,
+            "kappa": 0x03BA,
+            "lambda": 0x03BB,
+            "mu": 0x03BC,
+            "nu": 0x03BD,
+            "xi": 0x03BE,
+            "omicron": 0x03BF,
+            "pi": 0x03C0,
+            "rho": 0x03C1,
+            "sigmaf": 0x03C2,
+            "sigma": 0x03C3,
+            "tau": 0x03C4,
+            "upsilon": 0x03C5,
+            "phi": 0x03C6,
+            "chi": 0x03C7,
+            "psi": 0x03C8,
+            "omega": 0x03C9,
+            "thetasym": 0x03D1,
+            "upsih": 0x03D2,
+            "piv": 0x03D6,
+            "ensp": 0x2002,
+            "emsp": 0x2003,
+            "thinsp": 0x2009,
+            "zwnj": 0x200C,
+            "zwj": 0x200D,
+            "lrm": 0x200E,
+            "rlm": 0x200F,
+            "ndash": 0x2013,
+            "mdash": 0x2014,
+            "lsquo": 0x2018,
+            "rsquo": 0x2019,
+            "sbquo": 0x201A,
+            "ldquo": 0x201C,
+            "rdquo": 0x201D,
+            "bdquo": 0x201E,
+            "dagger": 0x2020,
+            "Dagger": 0x2021,
+            "bull": 0x2022,
+            "hellip": 0x2026,
+            "permil": 0x2030,
+            "prime": 0x2032,
+            "Prime": 0x2033,
+            "lsaquo": 0x2039,
+            "rsaquo": 0x203A,
+            "oline": 0x203E,
+            "frasl": 0x2044,
+            "euro": 0x20AC,
+            "image": 0x2111,
+            "weierp": 0x2118,
+            "real": 0x211C,
+            "trade": 0x2122,
+            "alefsym": 0x2135,
+            "larr": 0x2190,
+            "uarr": 0x2191,
+            "rarr": 0x2192,
+            "darr": 0x2193,
+            "harr": 0x2194,
+            "crarr": 0x21B5,
+            "lArr": 0x21D0,
+            "uArr": 0x21D1,
+            "rArr": 0x21D2,
+            "dArr": 0x21D3,
+            "hArr": 0x21D4,
+            "forall": 0x2200,
+            "part": 0x2202,
+            "exist": 0x2203,
+            "empty": 0x2205,
+            "nabla": 0x2207,
+            "isin": 0x2208,
+            "notin": 0x2209,
+            "ni": 0x220B,
+            "prod": 0x220F,
+            "sum": 0x2211,
+            "minus": 0x2212,
+            "lowast": 0x2217,
+            "radic": 0x221A,
+            "prop": 0x221D,
+            "infin": 0x221E,
+            "ang": 0x2220,
+            "and": 0x2227,
+            "or": 0x2228,
+            "cap": 0x2229,
+            "cup": 0x222A,
+            "int": 0x222B,
+            "there4": 0x2234,
+            "sim": 0x223C,
+            "cong": 0x2245,
+            "asymp": 0x2248,
+            "ne": 0x2260,
+            "equiv": 0x2261,
+            "le": 0x2264,
+            "ge": 0x2265,
+            "sub": 0x2282,
+            "sup": 0x2283,
+            "nsub": 0x2284,
+            "sube": 0x2286,
+            "supe": 0x2287,
+            "oplus": 0x2295,
+            "otimes": 0x2297,
+            "perp": 0x22A5,
+            "sdot": 0x22C5,
+            "lceil": 0x2308,
+            "rceil": 0x2309,
+            "lfloor": 0x230A,
+            "rfloor": 0x230B,
+            "lang": 0x2329,
+            "rang": 0x232A,
+            "loz": 0x25CA,
+            "spades": 0x2660,
+            "clubs": 0x2663,
+            "hearts": 0x2665,
+            "diams": 0x2666
+        });
+    }
+}

src/compiler/transformers/module/es6.ts

@@ -0,0 +1,140 @@
+/// <reference path="../../factory.ts" />
+/// <reference path="../../visitor.ts" />
+
+/*@internal*/
+namespace ts {
+    export function transformES6Module(context: TransformationContext) {
+        const compilerOptions = context.getCompilerOptions();
+        const resolver = context.getEmitResolver();
+
+        let currentSourceFile: SourceFile;
+
+        return transformSourceFile;
+
+        function transformSourceFile(node: SourceFile) {
+            if (isExternalModule(node) || compilerOptions.isolatedModules) {
+                currentSourceFile = node;
+                return visitEachChild(node, visitor, context);
+            }
+            return node;
+        }
+
+        function visitor(node: Node): VisitResult<Node> {
+            switch (node.kind) {
+                case SyntaxKind.ImportDeclaration:
+                    return visitImportDeclaration(<ImportDeclaration>node);
+                case SyntaxKind.ImportEqualsDeclaration:
+                    return visitImportEqualsDeclaration(<ImportEqualsDeclaration>node);
+                case SyntaxKind.ImportClause:
+                    return visitImportClause(<ImportClause>node);
+                case SyntaxKind.NamedImports:
+                case SyntaxKind.NamespaceImport:
+                    return visitNamedBindings(<NamedImportBindings>node);
+                case SyntaxKind.ImportSpecifier:
+                    return visitImportSpecifier(<ImportSpecifier>node);
+                case SyntaxKind.ExportAssignment:
+                    return visitExportAssignment(<ExportAssignment>node);
+                case SyntaxKind.ExportDeclaration:
+                    return visitExportDeclaration(<ExportDeclaration>node);
+                case SyntaxKind.NamedExports:
+                    return visitNamedExports(<NamedExports>node);
+                case SyntaxKind.ExportSpecifier:
+                    return visitExportSpecifier(<ExportSpecifier>node);
+            }
+
+            return node;
+        }
+
+        function visitExportAssignment(node: ExportAssignment): ExportAssignment {
+            if (node.isExportEquals) {
+                return undefined; // do not emit export equals for ES6
+            }
+            const original = getOriginalNode(node);
+            return nodeIsSynthesized(original) || resolver.isValueAliasDeclaration(original) ? node : undefined;
+        }
+
+        function visitExportDeclaration(node: ExportDeclaration): ExportDeclaration {
+            if (!node.exportClause) {
+                return resolver.moduleExportsSomeValue(node.moduleSpecifier) ? node : undefined;
+            }
+            if (!resolver.isValueAliasDeclaration(node)) {
+                return undefined;
+            }
+            const newExportClause = visitNode(node.exportClause, visitor, isNamedExports, /*optional*/ true);
+            if (node.exportClause === newExportClause) {
+                return node;
+            }
+            return newExportClause
+                ? createExportDeclaration(
+                    /*decorators*/ undefined,
+                    /*modifiers*/ undefined,
+                    newExportClause,
+                    node.moduleSpecifier)
+                : undefined;
+        }
+
+        function visitNamedExports(node: NamedExports): NamedExports {
+            const newExports = visitNodes(node.elements, visitor, isExportSpecifier);
+            if (node.elements === newExports) {
+                return node;
+            }
+            return newExports.length ? createNamedExports(newExports) : undefined;
+        }
+
+        function visitExportSpecifier(node: ExportSpecifier): ExportSpecifier {
+            return resolver.isValueAliasDeclaration(node) ? node : undefined;
+        }
+
+        function visitImportEqualsDeclaration(node: ImportEqualsDeclaration): ImportEqualsDeclaration {
+            return !isExternalModuleImportEqualsDeclaration(node) || resolver.isReferencedAliasDeclaration(node) ? node : undefined;
+        }
+
+        function visitImportDeclaration(node: ImportDeclaration) {
+            if (node.importClause) {
+                const newImportClause = visitNode(node.importClause, visitor, isImportClause);
+                if (!newImportClause.name && !newImportClause.namedBindings) {
+                    return undefined;
+                }
+                else if (newImportClause !== node.importClause) {
+                    return createImportDeclaration(
+                        /*decorators*/ undefined,
+                        /*modifiers*/ undefined,
+                        newImportClause,
+                        node.moduleSpecifier);
+                }
+            }
+            return node;
+        }
+
+        function visitImportClause(node: ImportClause): ImportClause {
+            let newDefaultImport = node.name;
+            if (!resolver.isReferencedAliasDeclaration(node)) {
+                newDefaultImport = undefined;
+            }
+            const newNamedBindings = visitNode(node.namedBindings, visitor, isNamedImportBindings, /*optional*/ true);
+            return newDefaultImport !== node.name || newNamedBindings !== node.namedBindings
+                ? createImportClause(newDefaultImport, newNamedBindings)
+                : node;
+        }
+
+        function visitNamedBindings(node: NamedImportBindings): VisitResult<NamedImportBindings> {
+            if (node.kind === SyntaxKind.NamespaceImport) {
+                return resolver.isReferencedAliasDeclaration(node) ? node : undefined;
+            }
+            else {
+                const newNamedImportElements = visitNodes((<NamedImports>node).elements, visitor, isImportSpecifier);
+                if (!newNamedImportElements || newNamedImportElements.length == 0) {
+                    return undefined;
+                }
+                if (newNamedImportElements === (<NamedImports>node).elements) {
+                    return node;
+                }
+                return createNamedImports(newNamedImportElements);
+            }
+        }
+
+        function visitImportSpecifier(node: ImportSpecifier) {
+            return resolver.isReferencedAliasDeclaration(node) ? node : undefined;
+        }
+    }
+}

src/compiler/tsc.ts

@@ -6,6 +6,11 @@ namespace ts {
         fileWatcher?: FileWatcher;
     }
 
+    interface Statistic {
+        name: string;
+        value: string;
+    }
+
     const defaultFormatDiagnosticsHost: FormatDiagnosticsHost = {
         getCurrentDirectory: () => sys.getCurrentDirectory(),
         getNewLine: () => sys.newLine,
@@ -230,18 +235,6 @@ namespace ts {
         return s;
     }
 
-    function reportStatisticalValue(name: string, value: string) {
-        sys.write(padRight(name + ":", 12) + padLeft(value.toString(), 10) + sys.newLine);
-    }
-
-    function reportCountStatistic(name: string, count: number) {
-        reportStatisticalValue(name, "" + count);
-    }
-
-    function reportTimeStatistic(name: string, time: number) {
-        reportStatisticalValue(name, (time / 1000).toFixed(2) + "s");
-    }
-
     function isJSONSupported() {
         return typeof JSON === "object" && typeof JSON.parse === "function";
     }
@@ -489,10 +482,7 @@ namespace ts {
             sourceFile.fileWatcher.close();
             sourceFile.fileWatcher = undefined;
             if (removed) {
-                const index = rootFileNames.indexOf(sourceFile.fileName);
-                if (index >= 0) {
-                    rootFileNames.splice(index, 1);
-                }
+                unorderedRemoveItem(rootFileNames, sourceFile.fileName);
             }
             startTimerForRecompilation();
         }
@@ -550,7 +540,11 @@ namespace ts {
 
     function compile(fileNames: string[], compilerOptions: CompilerOptions, compilerHost: CompilerHost) {
         const hasDiagnostics = compilerOptions.diagnostics || compilerOptions.extendedDiagnostics;
-        if (hasDiagnostics) performance.enable();
+        let statistics: Statistic[];
+        if (hasDiagnostics) {
+            performance.enable();
+            statistics = [];
+        }
 
         const program = createProgram(fileNames, compilerOptions, compilerHost);
         const exitStatus = compileProgram();
@@ -594,6 +588,7 @@ namespace ts {
                 reportTimeStatistic("Emit time", emitTime);
             }
             reportTimeStatistic("Total time", programTime + bindTime + checkTime + emitTime);
+            reportStatistics();
 
             performance.disable();
         }
@@ -635,6 +630,36 @@ namespace ts {
             }
             return ExitStatus.Success;
         }
+
+        function reportStatistics() {
+            let nameSize = 0;
+            let valueSize = 0;
+            for (const { name, value } of statistics) {
+                if (name.length > nameSize) {
+                    nameSize = name.length;
+                }
+
+                if (value.length > valueSize) {
+                    valueSize = value.length;
+                }
+            }
+
+            for (const { name, value } of statistics) {
+                sys.write(padRight(name + ":", nameSize + 2) + padLeft(value.toString(), valueSize) + sys.newLine);
+            }
+        }
+
+        function reportStatisticalValue(name: string, value: string) {
+            statistics.push({ name, value });
+        }
+
+        function reportCountStatistic(name: string, count: number) {
+            reportStatisticalValue(name, "" + count);
+        }
+
+        function reportTimeStatistic(name: string, time: number) {
+            reportStatisticalValue(name, (time / 1000).toFixed(2) + "s");
+        }
     }
 
     function printVersion() {
@@ -771,4 +796,8 @@ namespace ts {
     }
 }
 
+if (ts.sys.tryEnableSourceMapsForHost && /^development$/i.test(ts.sys.getEnvironmentVariable("NODE_ENV"))) {
+    ts.sys.tryEnableSourceMapsForHost();
+}
+
 ts.executeCommandLine(ts.sys.args);

src/compiler/tsconfig.json

@@ -20,6 +20,19 @@
         "utilities.ts",
         "binder.ts",
         "checker.ts",
+        "factory.ts",
+        "visitor.ts",
+        "transformers/ts.ts",
+        "transformers/jsx.ts",
+        "transformers/es7.ts",
+        "transformers/es6.ts",
+        "transformers/generators.ts",
+        "transformers/destructuring.ts",
+        "transformers/module/module.ts",
+        "transformers/module/system.ts",
+        "transformers/module/es6.ts",
+        "transformer.ts",
+        "comments.ts",
         "sourcemap.ts",
         "declarationEmitter.ts",
         "emitter.ts",

src/compiler/types.ts

@@ -357,11 +357,18 @@ namespace ts {
 
         // Synthesized list
         SyntaxList,
+
+        // Transformation nodes
+        NotEmittedStatement,
+        PartiallyEmittedExpression,
+
         // Enum value count
         Count,
         // Markers
         FirstAssignment = EqualsToken,
         LastAssignment = CaretEqualsToken,
+        FirstCompoundAssignment = PlusEqualsToken,
+        LastCompoundAssignment = CaretEqualsToken,
         FirstReservedWord = BreakKeyword,
         LastReservedWord = WithKeyword,
         FirstKeyword = BreakKeyword,
@@ -390,6 +397,45 @@ namespace ts {
     }
 
     export const enum NodeFlags {
+        None =               0,
+        Let =                1 << 0,  // Variable declaration
+        Const =              1 << 1,  // Variable declaration
+        NestedNamespace =    1 << 2,  // Namespace declaration
+        Synthesized =        1 << 3,  // Node was synthesized during transformation
+        Namespace =          1 << 4,  // Namespace declaration
+        ExportContext =      1 << 5,  // Export context (initialized by binding)
+        ContainsThis =       1 << 6,  // Interface contains references to "this"
+        HasImplicitReturn =  1 << 7,  // If function implicitly returns on one of codepaths (initialized by binding)
+        HasExplicitReturn =  1 << 8,  // If function has explicit reachable return on one of codepaths (initialized by binding)
+        GlobalAugmentation = 1 << 9,  // Set if module declaration is an augmentation for the global scope
+        HasClassExtends =    1 << 10, // If the file has a non-ambient class with an extends clause in ES5 or lower (initialized by binding)
+        HasDecorators =      1 << 11, // If the file has decorators (initialized by binding)
+        HasParamDecorators = 1 << 12, // If the file has parameter decorators (initialized by binding)
+        HasAsyncFunctions =  1 << 13, // If the file has async functions (initialized by binding)
+        HasJsxSpreadAttributes = 1 << 14, // If the file as JSX spread attributes (initialized by binding)
+        DisallowInContext =  1 << 15, // If node was parsed in a context where 'in-expressions' are not allowed
+        YieldContext =       1 << 16, // If node was parsed in the 'yield' context created when parsing a generator
+        DecoratorContext =   1 << 17, // If node was parsed as part of a decorator
+        AwaitContext =       1 << 18, // If node was parsed in the 'await' context created when parsing an async function
+        ThisNodeHasError =   1 << 19, // If the parser encountered an error when parsing the code that created this node
+        JavaScriptFile =     1 << 20, // If node was parsed in a JavaScript
+        ThisNodeOrAnySubNodesHasError = 1 << 21, // If this node or any of its children had an error
+        HasAggregatedChildData = 1 << 22, // If we've computed data from children and cached it in this node
+
+        BlockScoped = Let | Const,
+
+        ReachabilityCheckFlags = HasImplicitReturn | HasExplicitReturn,
+        EmitHelperFlags = HasClassExtends | HasDecorators | HasParamDecorators | HasAsyncFunctions | HasJsxSpreadAttributes,
+        ReachabilityAndEmitFlags = ReachabilityCheckFlags | EmitHelperFlags,
+
+        // Parsing context flags
+        ContextFlags = DisallowInContext | YieldContext | DecoratorContext | AwaitContext | JavaScriptFile,
+
+        // Exclude these flags when parsing a Type
+        TypeExcludesFlags = YieldContext | AwaitContext,
+    }
+
+    export const enum ModifierFlags {
         None =               0,
         Export =             1 << 0,  // Declarations
         Ambient =            1 << 1,  // Declarations
@@ -401,43 +447,14 @@ namespace ts {
         Abstract =           1 << 7,  // Class/Method/ConstructSignature
         Async =              1 << 8,  // Property/Method/Function
         Default =            1 << 9,  // Function/Class (export default declaration)
-        Let =                1 << 10,  // Variable declaration
-        Const =              1 << 11,  // Variable declaration
-        Namespace =          1 << 12,  // Namespace declaration
-        ExportContext =      1 << 13,  // Export context (initialized by binding)
-        ContainsThis =       1 << 14,  // Interface contains references to "this"
-        HasImplicitReturn =  1 << 15,  // If function implicitly returns on one of codepaths (initialized by binding)
-        HasExplicitReturn =  1 << 16,  // If function has explicit reachable return on one of codepaths (initialized by binding)
-        GlobalAugmentation = 1 << 17,  // Set if module declaration is an augmentation for the global scope
-        HasClassExtends =    1 << 18,  // If the file has a non-ambient class with an extends clause in ES5 or lower (initialized by binding)
-        HasDecorators =      1 << 19,  // If the file has decorators (initialized by binding)
-        HasParamDecorators = 1 << 20,  // If the file has parameter decorators (initialized by binding)
-        HasAsyncFunctions =  1 << 21,  // If the file has async functions (initialized by binding)
-        DisallowInContext =  1 << 22,  // If node was parsed in a context where 'in-expressions' are not allowed
-        YieldContext =       1 << 23,  // If node was parsed in the 'yield' context created when parsing a generator
-        DecoratorContext =   1 << 24,  // If node was parsed as part of a decorator
-        AwaitContext =       1 << 25,  // If node was parsed in the 'await' context created when parsing an async function
-        ThisNodeHasError =   1 << 26,  // If the parser encountered an error when parsing the code that created this node
-        JavaScriptFile =     1 << 27,  // If node was parsed in a JavaScript
-        ThisNodeOrAnySubNodesHasError = 1 << 28,  // If this node or any of its children had an error
-        HasAggregatedChildData = 1 << 29,  // If we've computed data from children and cached it in this node
-        HasJsxSpreadAttribute = 1 << 30,
+        Const =              1 << 11, // Variable declaration
+
+        HasComputedFlags =   1 << 29, // Modifier flags have been computed
 
-        Modifier = Export | Ambient | Public | Private | Protected | Static | Abstract | Default | Async | Readonly,
         AccessibilityModifier = Public | Private | Protected,
         // Accessibility modifiers and 'readonly' can be attached to a parameter in a constructor to make it a property.
         ParameterPropertyModifier = AccessibilityModifier | Readonly,
-        BlockScoped = Let | Const,
-
-        ReachabilityCheckFlags = HasImplicitReturn | HasExplicitReturn,
-        EmitHelperFlags = HasClassExtends | HasDecorators | HasParamDecorators | HasAsyncFunctions,
-        ReachabilityAndEmitFlags = ReachabilityCheckFlags | EmitHelperFlags,
-
-        // Parsing context flags
-        ContextFlags = DisallowInContext | YieldContext | DecoratorContext | AwaitContext | JavaScriptFile,
-
-        // Exclude these flags when parsing a Type
-        TypeExcludesFlags = YieldContext | AwaitContext,
+        NonPublicAccessibilityModifier = Private | Protected,
     }
 
     export const enum JsxFlags {
@@ -460,26 +477,30 @@ namespace ts {
     export interface Node extends TextRange {
         kind: SyntaxKind;
         flags: NodeFlags;
+        /* @internal */ modifierFlagsCache?: ModifierFlags;
+        /* @internal */ transformFlags?: TransformFlags;
         decorators?: NodeArray<Decorator>;              // Array of decorators (in document order)
-        modifiers?: ModifiersArray;                     // Array of modifiers
+        modifiers?: NodeArray<Modifier>;                // Array of modifiers
         /* @internal */ id?: number;                    // Unique id (used to look up NodeLinks)
-        parent?: Node;                                  // Parent node (initialized by binding
+        parent?: Node;                                  // Parent node (initialized by binding)
+        /* @internal */ original?: Node;                // The original node if this is an updated node.
+        /* @internal */ startsOnNewLine?: boolean;      // Whether a synthesized node should start on a new line (used by transforms).
         /* @internal */ jsDocComments?: JSDocComment[]; // JSDoc for the node, if it has any.  Only for .js files.
         /* @internal */ symbol?: Symbol;                // Symbol declared by node (initialized by binding)
         /* @internal */ locals?: SymbolTable;           // Locals associated with node (initialized by binding)
         /* @internal */ nextContainer?: Node;           // Next container in declaration order (initialized by binding)
         /* @internal */ localSymbol?: Symbol;           // Local symbol declared by node (initialized by binding only for exported nodes)
         /* @internal */ flowNode?: FlowNode;            // Associated FlowNode (initialized by binding)
+        /* @internal */ transformId?: number;           // Associates transient transformation properties with a specific transformation (initialized by transformation).
+        /* @internal */ emitFlags?: NodeEmitFlags;      // Transient emit flags for a synthesized node (initialized by transformation).
+        /* @internal */ sourceMapRange?: TextRange;     // Transient custom sourcemap range for a synthesized node (initialized by transformation).
+        /* @internal */ commentRange?: TextRange;       // Transient custom comment range for a synthesized node (initialized by transformation).
     }
 
-    export interface NodeArray<T> extends Array<T>, TextRange {
+    export interface NodeArray<T extends Node> extends Array<T>, TextRange {
         hasTrailingComma?: boolean;
     }
 
-    export interface ModifiersArray extends NodeArray<Modifier> {
-        flags: NodeFlags;
-    }
-
     export interface Token extends Node {
         __tokenTag: any;
     }
@@ -496,10 +517,26 @@ namespace ts {
     // @kind(SyntaxKind.StaticKeyword)
     export interface Modifier extends Token { }
 
+    /*@internal*/
+    export const enum GeneratedIdentifierKind {
+        None,   // Not automatically generated.
+        Auto,   // Automatically generated identifier.
+        Loop,   // Automatically generated identifier with a preference for '_i'.
+        Unique, // Unique name based on the 'text' property.
+        Node,   // Unique name based on the node in the 'original' property.
+    }
+
     // @kind(SyntaxKind.Identifier)
     export interface Identifier extends PrimaryExpression {
         text: string;                                  // Text of identifier (with escapes converted to characters)
         originalKeywordKind?: SyntaxKind;              // Original syntaxKind which get set so that we can report an error later
+        /*@internal*/ autoGenerateKind?: GeneratedIdentifierKind; // Specifies whether to auto-generate the text for an identifier.
+        /*@internal*/ autoGenerateId?: number;         // Ensures unique generated identifiers get unique names, but clones get the same name.
+    }
+
+    // Transient identifier node (marked by id === -1)
+    export interface TransientIdentifier extends Identifier {
+        resolvedSymbol: Symbol;
     }
 
     // @kind(SyntaxKind.QualifiedName)
@@ -556,10 +593,12 @@ namespace ts {
     // @kind(SyntaxKind.ConstructSignature)
     export interface ConstructSignatureDeclaration extends SignatureDeclaration, TypeElement { }
 
+    export type BindingName = Identifier | BindingPattern;
+
     // @kind(SyntaxKind.VariableDeclaration)
     export interface VariableDeclaration extends Declaration {
         parent?: VariableDeclarationList;
-        name: Identifier | BindingPattern;  // Declared variable name
+        name: BindingName;                  // Declared variable name
         type?: TypeNode;                    // Optional type annotation
         initializer?: Expression;           // Optional initializer
     }
@@ -572,7 +611,7 @@ namespace ts {
     // @kind(SyntaxKind.Parameter)
     export interface ParameterDeclaration extends Declaration {
         dotDotDotToken?: Node;              // Present on rest parameter
-        name: Identifier | BindingPattern;  // Declared parameter name
+        name: BindingName;                  // Declared parameter name
         questionToken?: Node;               // Present on optional parameter
         type?: TypeNode;                    // Optional type annotation
         initializer?: Expression;           // Optional initializer
@@ -582,7 +621,7 @@ namespace ts {
     export interface BindingElement extends Declaration {
         propertyName?: PropertyName;        // Binding property name (in object binding pattern)
         dotDotDotToken?: Node;              // Present on rest binding element
-        name: Identifier | BindingPattern;  // Declared binding element name
+        name: BindingName;                  // Declared binding element name
         initializer?: Expression;           // Optional initializer
     }
 
@@ -810,6 +849,8 @@ namespace ts {
     // @kind(SyntaxKind.StringLiteral)
     export interface StringLiteral extends LiteralExpression {
         _stringLiteralBrand: any;
+        /* @internal */
+        textSourceNode?: Identifier | StringLiteral; // Allows a StringLiteral to get its text from another node (used by transforms).
     }
 
     // Note: 'brands' in our syntax nodes serve to give us a small amount of nominal typing.
@@ -827,6 +868,14 @@ namespace ts {
     // @kind(SyntaxKind.OmittedExpression)
     export interface OmittedExpression extends Expression { }
 
+    // Represents an expression that is elided as part of a transformation to emit comments on a
+    // not-emitted node. The 'expression' property of a NotEmittedExpression should be emitted.
+    // @internal
+    // @kind(SyntaxKind.NotEmittedExpression)
+    export interface PartiallyEmittedExpression extends LeftHandSideExpression {
+        expression: Expression;
+    }
+
     export interface UnaryExpression extends Expression {
         _unaryExpressionBrand: any;
     }
@@ -937,13 +986,18 @@ namespace ts {
     // The text property of a LiteralExpression stores the interpreted value of the literal in text form. For a StringLiteral,
     // or any literal of a template, this means quotes have been removed and escapes have been converted to actual characters.
     // For a NumericLiteral, the stored value is the toString() representation of the number. For example 1, 1.00, and 1e0 are all stored as just "1".
-    // @kind(SyntaxKind.NumericLiteral)
     // @kind(SyntaxKind.RegularExpressionLiteral)
     // @kind(SyntaxKind.NoSubstitutionTemplateLiteral)
     export interface LiteralExpression extends LiteralLikeNode, PrimaryExpression {
         _literalExpressionBrand: any;
     }
 
+    // @kind(SyntaxKind.NumericLiteral)
+    export interface NumericLiteral extends LiteralExpression {
+        _numericLiteralBrand: any;
+        trailingComment?: string;
+    }
+
     // @kind(SyntaxKind.TemplateHead)
     // @kind(SyntaxKind.TemplateMiddle)
     // @kind(SyntaxKind.TemplateTail)
@@ -951,6 +1005,8 @@ namespace ts {
         _templateLiteralFragmentBrand: any;
     }
 
+    export type Template = TemplateExpression | LiteralExpression;
+
     // @kind(SyntaxKind.TemplateExpression)
     export interface TemplateExpression extends PrimaryExpression {
         head: TemplateLiteralFragment;
@@ -1029,7 +1085,7 @@ namespace ts {
     // @kind(SyntaxKind.TaggedTemplateExpression)
     export interface TaggedTemplateExpression extends MemberExpression {
         tag: LeftHandSideExpression;
-        template: LiteralExpression | TemplateExpression;
+        template: Template;
     }
 
     export type CallLikeExpression = CallExpression | NewExpression | TaggedTemplateExpression | Decorator;
@@ -1080,11 +1136,13 @@ namespace ts {
     /// Either the opening tag in a <Tag>...</Tag> pair, or the lone <Tag /> in a self-closing form
     export type JsxOpeningLikeElement = JsxSelfClosingElement | JsxOpeningElement;
 
+    export type JsxAttributeLike = JsxAttribute | JsxSpreadAttribute;
+
     // @kind(SyntaxKind.JsxAttribute)
     export interface JsxAttribute extends Node {
         name: Identifier;
         /// JSX attribute initializers are optional; <X y /> is sugar for <X y={true} />
-        initializer?: Expression;
+        initializer?: StringLiteral | JsxExpression;
     }
 
     // @kind(SyntaxKind.JsxSpreadAttribute)
@@ -1113,6 +1171,13 @@ namespace ts {
         _statementBrand: any;
     }
 
+    // Represents a statement that is elided as part of a transformation to emit comments on a
+    // not-emitted node.
+    // @internal
+    // @kind(SyntaxKind.NotEmittedStatement)
+    export interface NotEmittedStatement extends Statement {
+    }
+
     // @kind(SyntaxKind.EmptyStatement)
     export interface EmptyStatement extends Statement { }
 
@@ -1129,6 +1194,7 @@ namespace ts {
     // @kind(SyntaxKind.Block)
     export interface Block extends Statement {
         statements: NodeArray<Statement>;
+        /*@internal*/ multiLine?: boolean;
     }
 
     // @kind(SyntaxKind.VariableStatement)
@@ -1162,22 +1228,24 @@ namespace ts {
         expression: Expression;
     }
 
+    export type ForInitializer = VariableDeclarationList | Expression;
+
     // @kind(SyntaxKind.ForStatement)
     export interface ForStatement extends IterationStatement {
-        initializer?: VariableDeclarationList | Expression;
+        initializer?: ForInitializer;
         condition?: Expression;
         incrementor?: Expression;
     }
 
     // @kind(SyntaxKind.ForInStatement)
     export interface ForInStatement extends IterationStatement {
-        initializer: VariableDeclarationList | Expression;
+        initializer: ForInitializer;
         expression: Expression;
     }
 
     // @kind(SyntaxKind.ForOfStatement)
     export interface ForOfStatement extends IterationStatement {
-        initializer: VariableDeclarationList | Expression;
+        initializer: ForInitializer;
         expression: Expression;
     }
 
@@ -1307,7 +1375,7 @@ namespace ts {
     export interface EnumMember extends Declaration {
         // This does include ComputedPropertyName, but the parser will give an error
         // if it parses a ComputedPropertyName in an EnumMember
-        name: DeclarationName;
+        name: PropertyName;
         initializer?: Expression;
     }
 
@@ -1319,6 +1387,8 @@ namespace ts {
 
     export type ModuleBody = ModuleBlock | ModuleDeclaration;
 
+    export type ModuleName = Identifier | StringLiteral;
+
     // @kind(SyntaxKind.ModuleDeclaration)
     export interface ModuleDeclaration extends DeclarationStatement {
         name: Identifier | LiteralExpression;
@@ -1330,13 +1400,15 @@ namespace ts {
         statements: NodeArray<Statement>;
     }
 
+    export type ModuleReference = EntityName | ExternalModuleReference;
+
     // @kind(SyntaxKind.ImportEqualsDeclaration)
     export interface ImportEqualsDeclaration extends DeclarationStatement {
         name: Identifier;
 
         // 'EntityName' for an internal module reference, 'ExternalModuleReference' for an external
         // module reference.
-        moduleReference: EntityName | ExternalModuleReference;
+        moduleReference: ModuleReference;
     }
 
     // @kind(SyntaxKind.ExternalModuleReference)
@@ -1354,6 +1426,8 @@ namespace ts {
         moduleSpecifier: Expression;
     }
 
+    export type NamedImportBindings = NamespaceImport | NamedImports;
+
     // In case of:
     // import d from "mod" => name = d, namedBinding = undefined
     // import * as ns from "mod" => name = undefined, namedBinding: NamespaceImport = { name: ns }
@@ -1363,7 +1437,7 @@ namespace ts {
     // @kind(SyntaxKind.ImportClause)
     export interface ImportClause extends Declaration {
         name?: Identifier; // Default binding
-        namedBindings?: NamespaceImport | NamedImports;
+        namedBindings?: NamedImportBindings;
     }
 
     // @kind(SyntaxKind.NamespaceImport)
@@ -1702,6 +1776,8 @@ namespace ts {
         /* @internal */ imports: LiteralExpression[];
         /* @internal */ moduleAugmentations: LiteralExpression[];
         /* @internal */ patternAmbientModules?: PatternAmbientModule[];
+        // The synthesized identifier for an imported external helpers module.
+        /* @internal */ externalHelpersModuleName?: Identifier;
     }
 
     export interface ScriptReferenceHost {
@@ -1889,6 +1965,7 @@ namespace ts {
         getJsxElementAttributesType(elementNode: JsxOpeningLikeElement): Type;
         getJsxIntrinsicTagNames(): Symbol[];
         isOptionalParameter(node: ParameterDeclaration): boolean;
+        getAmbientModules(): Symbol[];
 
         // Should not be called directly.  Should only be accessed through the Program instance.
         /* @internal */ getDiagnostics(sourceFile?: SourceFile, cancellationToken?: CancellationToken): Diagnostic[];
@@ -2019,12 +2096,13 @@ namespace ts {
                                             // function that can be reached at runtime (e.g. a `class`
                                             // declaration or a `var` declaration for the static side
                                             // of a type, such as the global `Promise` type in lib.d.ts).
-        VoidType,                           // The TypeReferenceNode resolves to a Void-like type.
+        VoidNullableOrNeverType,            // The TypeReferenceNode resolves to a Void-like, Nullable, or Never type.
         NumberLikeType,                     // The TypeReferenceNode resolves to a Number-like type.
         StringLikeType,                     // The TypeReferenceNode resolves to a String-like type.
         BooleanType,                        // The TypeReferenceNode resolves to a Boolean-like type.
         ArrayLikeType,                      // The TypeReferenceNode resolves to an Array-like type.
         ESSymbolType,                       // The TypeReferenceNode resolves to the ESSymbol type.
+        Promise,                            // The TypeReferenceNode resolved to the global Promise constructor symbol.
         TypeWithCallSignature,              // The TypeReferenceNode resolves to a Function type or a type
                                             // with call signatures.
         ObjectType,                         // The TypeReferenceNode resolves to any other type.
@@ -2033,7 +2111,7 @@ namespace ts {
     /* @internal */
     export interface EmitResolver {
         hasGlobalName(name: string): boolean;
-        getReferencedExportContainer(node: Identifier): SourceFile | ModuleDeclaration | EnumDeclaration;
+        getReferencedExportContainer(node: Identifier, prefixLocals?: boolean): SourceFile | ModuleDeclaration | EnumDeclaration;
         getReferencedImportDeclaration(node: Identifier): Declaration;
         getReferencedDeclarationWithCollidingName(node: Identifier): Declaration;
         isDeclarationWithCollidingName(node: Declaration): boolean;
@@ -2053,7 +2131,7 @@ namespace ts {
         // Returns the constant value this property access resolves to, or 'undefined' for a non-constant
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         getReferencedValueDeclaration(reference: Identifier): Declaration;
-        getTypeReferenceSerializationKind(typeName: EntityName): TypeReferenceSerializationKind;
+        getTypeReferenceSerializationKind(typeName: EntityName, location?: Node): TypeReferenceSerializationKind;
         isOptionalParameter(node: ParameterDeclaration): boolean;
         moduleExportsSomeValue(moduleReferenceExpression: Expression): boolean;
         isArgumentsLocalBinding(node: Identifier): boolean;
@@ -2228,6 +2306,8 @@ namespace ts {
         BodyScopedClassBinding              = 0x00100000,  // Binding to a decorated class inside of the class's body.
         NeedsLoopOutParameter               = 0x00200000,  // Block scoped binding whose value should be explicitly copied outside of the converted loop
         AssignmentsMarked                   = 0x00400000,  // Parameter assignments have been marked
+        ClassWithConstructorReference       = 0x00800000,  // Class that contains a binding to its constructor inside of the class body.
+        ConstructorReferenceInClass         = 0x01000000,  // Binding to a class constructor inside of the class's body.
     }
 
     /* @internal */
@@ -2596,6 +2676,7 @@ namespace ts {
         experimentalDecorators?: boolean;
         forceConsistentCasingInFileNames?: boolean;
         /*@internal*/help?: boolean;
+        importHelpers?: boolean;
         /*@internal*/init?: boolean;
         inlineSourceMap?: boolean;
         inlineSources?: boolean;
@@ -2983,8 +3064,117 @@ namespace ts {
          * This method is a companion for 'resolveModuleNames' and is used to resolve 'types' references to actual type declaration files
          */
         resolveTypeReferenceDirectives?(typeReferenceDirectiveNames: string[], containingFile: string): ResolvedTypeReferenceDirective[];
+        getEnvironmentVariable?(name: string): string;
     }
 
+    /* @internal */
+    export const enum TransformFlags {
+        None = 0,
+
+        // Facts
+        // - Flags used to indicate that a node or subtree contains syntax that requires transformation.
+        TypeScript = 1 << 0,
+        ContainsTypeScript = 1 << 1,
+        Jsx = 1 << 2,
+        ContainsJsx = 1 << 3,
+        ES7 = 1 << 4,
+        ContainsES7 = 1 << 5,
+        ES6 = 1 << 6,
+        ContainsES6 = 1 << 7,
+        DestructuringAssignment = 1 << 8,
+        Generator = 1 << 9,
+        ContainsGenerator = 1 << 10,
+
+        // Markers
+        // - Flags used to indicate that a subtree contains a specific transformation.
+        ContainsDecorators = 1 << 11,
+        ContainsPropertyInitializer = 1 << 12,
+        ContainsLexicalThis = 1 << 13,
+        ContainsCapturedLexicalThis = 1 << 14,
+        ContainsLexicalThisInComputedPropertyName = 1 << 15,
+        ContainsDefaultValueAssignments = 1 << 16,
+        ContainsParameterPropertyAssignments = 1 << 17,
+        ContainsSpreadElementExpression = 1 << 18,
+        ContainsComputedPropertyName = 1 << 19,
+        ContainsBlockScopedBinding = 1 << 20,
+        ContainsBindingPattern = 1 << 21,
+        ContainsYield = 1 << 22,
+        ContainsHoistedDeclarationOrCompletion = 1 << 23,
+
+        HasComputedFlags = 1 << 29, // Transform flags have been computed.
+
+        // Assertions
+        // - Bitmasks that are used to assert facts about the syntax of a node and its subtree.
+        AssertTypeScript = TypeScript | ContainsTypeScript,
+        AssertJsx = Jsx | ContainsJsx,
+        AssertES7 = ES7 | ContainsES7,
+        AssertES6 = ES6 | ContainsES6,
+        AssertGenerator = Generator | ContainsGenerator,
+
+        // Scope Exclusions
+        // - Bitmasks that exclude flags from propagating out of a specific context
+        //   into the subtree flags of their container.
+        NodeExcludes = TypeScript | Jsx | ES7 | ES6 | DestructuringAssignment | Generator | HasComputedFlags,
+        ArrowFunctionExcludes = NodeExcludes | ContainsDecorators | ContainsDefaultValueAssignments | ContainsLexicalThis | ContainsParameterPropertyAssignments | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion,
+        FunctionExcludes = NodeExcludes | ContainsDecorators | ContainsDefaultValueAssignments | ContainsCapturedLexicalThis | ContainsLexicalThis | ContainsParameterPropertyAssignments | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion,
+        ConstructorExcludes = NodeExcludes | ContainsDefaultValueAssignments | ContainsLexicalThis | ContainsCapturedLexicalThis | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion,
+        MethodOrAccessorExcludes = NodeExcludes | ContainsDefaultValueAssignments | ContainsLexicalThis | ContainsCapturedLexicalThis | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion,
+        ClassExcludes = NodeExcludes | ContainsDecorators | ContainsPropertyInitializer | ContainsLexicalThis | ContainsCapturedLexicalThis | ContainsComputedPropertyName | ContainsParameterPropertyAssignments | ContainsLexicalThisInComputedPropertyName,
+        ModuleExcludes = NodeExcludes | ContainsDecorators | ContainsLexicalThis | ContainsCapturedLexicalThis | ContainsBlockScopedBinding | ContainsHoistedDeclarationOrCompletion,
+        TypeExcludes = ~ContainsTypeScript,
+        ObjectLiteralExcludes = NodeExcludes | ContainsDecorators | ContainsComputedPropertyName | ContainsLexicalThisInComputedPropertyName,
+        ArrayLiteralOrCallOrNewExcludes = NodeExcludes | ContainsSpreadElementExpression,
+        VariableDeclarationListExcludes = NodeExcludes | ContainsBindingPattern,
+        ParameterExcludes = NodeExcludes | ContainsBindingPattern,
+
+        // Masks
+        // - Additional bitmasks
+        TypeScriptClassSyntaxMask = ContainsParameterPropertyAssignments | ContainsPropertyInitializer | ContainsDecorators,
+        ES6FunctionSyntaxMask = ContainsCapturedLexicalThis | ContainsDefaultValueAssignments,
+    }
+
+    /* @internal */
+    export const enum NodeEmitFlags {
+        EmitEmitHelpers = 1 << 0,                // Any emit helpers should be written to this node.
+        EmitExportStar = 1 << 1,                 // The export * helper should be written to this node.
+        EmitSuperHelper = 1 << 2,                // Emit the basic _super helper for async methods.
+        EmitAdvancedSuperHelper = 1 << 3,        // Emit the advanced _super helper for async methods.
+        UMDDefine = 1 << 4,                      // This node should be replaced with the UMD define helper.
+        SingleLine = 1 << 5,                     // The contents of this node should be emitted on a single line.
+        AdviseOnEmitNode = 1 << 6,               // The printer should invoke the onEmitNode callback when printing this node.
+        NoSubstitution = 1 << 7,                 // Disables further substitution of an expression.
+        CapturesThis = 1 << 8,                   // The function captures a lexical `this`
+        NoLeadingSourceMap = 1 << 9,             // Do not emit a leading source map location for this node.
+        NoTrailingSourceMap = 1 << 10,           // Do not emit a trailing source map location for this node.
+        NoSourceMap = NoLeadingSourceMap | NoTrailingSourceMap, // Do not emit a source map location for this node.
+        NoNestedSourceMaps = 1 << 11,            // Do not emit source map locations for children of this node.
+        NoTokenLeadingSourceMaps = 1 << 12,      // Do not emit leading source map location for token nodes.
+        NoTokenTrailingSourceMaps = 1 << 13,     // Do not emit trailing source map location for token nodes.
+        NoTokenSourceMaps = NoTokenLeadingSourceMaps | NoTokenTrailingSourceMaps, // Do not emit source map locations for tokens of this node.
+        NoLeadingComments = 1 << 14,             // Do not emit leading comments for this node.
+        NoTrailingComments = 1 << 15,            // Do not emit trailing comments for this node.
+        NoComments = NoLeadingComments | NoTrailingComments, // Do not emit comments for this node.
+        NoNestedComments = 1 << 16,
+        ExportName = 1 << 17,                    // Ensure an export prefix is added for an identifier that points to an exported declaration with a local name (see SymbolFlags.ExportHasLocal).
+        LocalName = 1 << 18,                     // Ensure an export prefix is not added for an identifier that points to an exported declaration.
+        Indented = 1 << 19,                      // Adds an explicit extra indentation level for class and function bodies when printing (used to match old emitter).
+        NoIndentation = 1 << 20,                 // Do not indent the node.
+        AsyncFunctionBody = 1 << 21,
+        ReuseTempVariableScope = 1 << 22,        // Reuse the existing temp variable scope during emit.
+        CustomPrologue = 1 << 23,                // Treat the statement as if it were a prologue directive (NOTE: Prologue directives are *not* transformed).
+    }
+
+    /** Additional context provided to `visitEachChild` */
+    /* @internal */
+    export interface LexicalEnvironment {
+        /** Starts a new lexical environment. */
+        startLexicalEnvironment(): void;
+
+        /** Ends a lexical environment, returning any declarations. */
+        endLexicalEnvironment(): Statement[];
+    }
+
+
     export interface TextSpan {
         start: number;
         length: number;

src/harness/compilerRunner.ts

@@ -154,7 +154,7 @@ class CompilerBaselineRunner extends RunnerBase {
                 if (options.sourceMap || options.inlineSourceMap) {
                     Harness.Baseline.runBaseline(justName.replace(/\.tsx?$/, ".sourcemap.txt"), () => {
                         const record = result.getSourceMapRecord();
-                        if (options.noEmitOnError && result.errors.length !== 0 && record === undefined) {
+                        if ((options.noEmitOnError && result.errors.length !== 0) || record === undefined) {
                             // Because of the noEmitOnError option no files are created. We need to return null because baselining isn't required.
                             /* tslint:disable:no-null-keyword */
                             return null;

src/harness/fourslash.ts

@@ -263,22 +263,31 @@ namespace FourSlash {
         constructor(private basePath: string, private testType: FourSlashTestType, public testData: FourSlashData) {
             // Create a new Services Adapter
             this.cancellationToken = new TestCancellationToken();
-            const compilationOptions = convertGlobalOptionsToCompilerOptions(this.testData.globalOptions);
-            if (compilationOptions.typeRoots) {
-                compilationOptions.typeRoots = compilationOptions.typeRoots.map(p => ts.getNormalizedAbsolutePath(p, this.basePath));
-            }
+            let compilationOptions = convertGlobalOptionsToCompilerOptions(this.testData.globalOptions);
             compilationOptions.skipDefaultLibCheck = true;
 
-            const languageServiceAdapter = this.getLanguageServiceAdapter(testType, this.cancellationToken, compilationOptions);
-            this.languageServiceAdapterHost = languageServiceAdapter.getHost();
-            this.languageService = languageServiceAdapter.getLanguageService();
-
             // Initialize the language service with all the scripts
             let startResolveFileRef: FourSlashFile;
 
             ts.forEach(testData.files, file => {
                 // Create map between fileName and its content for easily looking up when resolveReference flag is specified
                 this.inputFiles[file.fileName] = file.content;
+
+                if (ts.getBaseFileName(file.fileName).toLowerCase() === "tsconfig.json") {
+                    const configJson = ts.parseConfigFileTextToJson(file.fileName, file.content);
+                    assert.isTrue(configJson.config !== undefined);
+
+                    // Extend our existing compiler options so that we can also support tsconfig only options
+                    if (configJson.config.compilerOptions) {
+                        const baseDirectory = ts.normalizePath(ts.getDirectoryPath(file.fileName));
+                        const tsConfig = ts.convertCompilerOptionsFromJson(configJson.config.compilerOptions, baseDirectory, file.fileName);
+
+                        if (!tsConfig.errors || !tsConfig.errors.length) {
+                            compilationOptions = ts.extend(compilationOptions, tsConfig.options);
+                        }
+                    }
+                }
+
                 if (!startResolveFileRef && file.fileOptions[metadataOptionNames.resolveReference] === "true") {
                     startResolveFileRef = file;
                 }
@@ -288,6 +297,15 @@ namespace FourSlash {
                 }
             });
 
+
+            if (compilationOptions.typeRoots) {
+                compilationOptions.typeRoots = compilationOptions.typeRoots.map(p => ts.getNormalizedAbsolutePath(p, this.basePath));
+            }
+
+            const languageServiceAdapter = this.getLanguageServiceAdapter(testType, this.cancellationToken, compilationOptions);
+            this.languageServiceAdapterHost = languageServiceAdapter.getHost();
+            this.languageService = languageServiceAdapter.getLanguageService();
+
             if (startResolveFileRef) {
                 // Add the entry-point file itself into the languageServiceShimHost
                 this.languageServiceAdapterHost.addScript(startResolveFileRef.fileName, startResolveFileRef.content, /*isRootFile*/ true);
@@ -342,6 +360,7 @@ namespace FourSlash {
                 InsertSpaceAfterFunctionKeywordForAnonymousFunctions: false,
                 InsertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis: false,
                 InsertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets: false,
+                InsertSpaceAfterOpeningAndBeforeClosingNonemptyBraces: true,
                 InsertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces: false,
                 InsertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces: false,
                 PlaceOpenBraceOnNewLineForFunctions: false,
@@ -525,6 +544,67 @@ namespace FourSlash {
             }
         }
 
+        public verifyGoToDefinitionIs(endMarker: string | string[]) {
+            this.verifyGoToDefinitionWorker(endMarker instanceof Array ? endMarker : [endMarker]);
+        }
+
+        public verifyGoToDefinition(arg0: any, endMarkerNames?: string | string[]) {
+            if (endMarkerNames) {
+                this.verifyGoToDefinitionPlain(arg0, endMarkerNames);
+            }
+            else if (arg0 instanceof Array) {
+                const pairs: [string | string[], string | string[]][] = arg0;
+                for (const [start, end] of pairs) {
+                    this.verifyGoToDefinitionPlain(start, end);
+                }
+            }
+            else {
+                const obj: { [startMarkerName: string]: string | string[] } = arg0;
+                for (const startMarkerName in obj) {
+                    if (ts.hasProperty(obj, startMarkerName)) {
+                        this.verifyGoToDefinitionPlain(startMarkerName, obj[startMarkerName]);
+                    }
+                }
+            }
+        }
+
+        private verifyGoToDefinitionPlain(startMarkerNames: string | string[], endMarkerNames: string | string[]) {
+            if (startMarkerNames instanceof Array) {
+                for (const start of startMarkerNames) {
+                    this.verifyGoToDefinitionSingle(start, endMarkerNames);
+                }
+            }
+            else {
+                this.verifyGoToDefinitionSingle(startMarkerNames, endMarkerNames);
+            }
+        }
+
+        public verifyGoToDefinitionForMarkers(markerNames: string[]) {
+            for (const markerName of markerNames) {
+                this.verifyGoToDefinitionSingle(`${markerName}Reference`, `${markerName}Definition`);
+            }
+        }
+
+        private verifyGoToDefinitionSingle(startMarkerName: string, endMarkerNames: string | string[]) {
+            this.goToMarker(startMarkerName);
+            this.verifyGoToDefinitionWorker(endMarkerNames instanceof Array ? endMarkerNames : [endMarkerNames]);
+        }
+
+        private verifyGoToDefinitionWorker(endMarkers: string[]) {
+            const definitions = this.languageService.getDefinitionAtPosition(this.activeFile.fileName, this.currentCaretPosition) || [];
+
+            if (endMarkers.length !== definitions.length) {
+                this.raiseError(`goToDefinitions failed - expected to find ${endMarkers.length} definitions but got ${definitions.length}`);
+            }
+
+            for (let i = 0; i < endMarkers.length; i++) {
+                const marker = this.getMarkerByName(endMarkers[i]), definition = definitions[i];
+                if (marker.fileName !== definition.fileName || marker.position !== definition.textSpan.start) {
+                    this.raiseError(`goToDefinition failed for definition ${i}: expected ${marker.fileName} at ${marker.position}, got ${definition.fileName} at ${definition.textSpan.start}`);
+                }
+            }
+        }
+
         public verifyGetEmitOutputForCurrentFile(expected: string): void {
             const emit = this.languageService.getEmitOutput(this.activeFile.fileName);
             if (emit.outputFiles.length !== 1) {
@@ -669,10 +749,10 @@ namespace FourSlash {
             }
         }
 
-        public verifyCompletionListContains(symbol: string, text?: string, documentation?: string, kind?: string) {
+        public verifyCompletionListContains(symbol: string, text?: string, documentation?: string, kind?: string, spanIndex?: number) {
             const completions = this.getCompletionListAtCaret();
             if (completions) {
-                this.assertItemInCompletionList(completions.entries, symbol, text, documentation, kind);
+                this.assertItemInCompletionList(completions.entries, symbol, text, documentation, kind, spanIndex);
             }
             else {
                 this.raiseError(`No completions at position '${this.currentCaretPosition}' when looking for '${symbol}'.`);
@@ -688,25 +768,32 @@ namespace FourSlash {
          * @param expectedText the text associated with the symbol
          * @param expectedDocumentation the documentation text associated with the symbol
          * @param expectedKind the kind of symbol (see ScriptElementKind)
+         * @param spanIndex the index of the range that the completion item's replacement text span should match
          */
-        public verifyCompletionListDoesNotContain(symbol: string, expectedText?: string, expectedDocumentation?: string, expectedKind?: string) {
+        public verifyCompletionListDoesNotContain(symbol: string, expectedText?: string, expectedDocumentation?: string, expectedKind?: string, spanIndex?: number) {
             const that = this;
+            let replacementSpan: ts.TextSpan;
+            if (spanIndex !== undefined) {
+                replacementSpan = this.getTextSpanForRangeAtIndex(spanIndex);
+            }
+
             function filterByTextOrDocumentation(entry: ts.CompletionEntry) {
                 const details = that.getCompletionEntryDetails(entry.name);
                 const documentation = ts.displayPartsToString(details.documentation);
                 const text = ts.displayPartsToString(details.displayParts);
-                if (expectedText && expectedDocumentation) {
-                    return (documentation === expectedDocumentation && text === expectedText) ? true : false;
+
+                // If any of the expected values are undefined, assume that users don't
+                // care about them.
+                if (replacementSpan && !TestState.textSpansEqual(replacementSpan, entry.replacementSpan)) {
+                    return false;
                 }
-                else if (expectedText && !expectedDocumentation) {
-                    return text === expectedText ? true : false;
+                else if (expectedText && text !== expectedText) {
+                    return false;
                 }
-                else if (expectedDocumentation && !expectedText) {
-                    return documentation === expectedDocumentation ? true : false;
+                else if (expectedDocumentation && documentation !== expectedDocumentation) {
+                    return false;
                 }
-                // Because expectedText and expectedDocumentation are undefined, we assume that
-                // users don"t care to compare them so we will treat that entry as if the entry has matching text and documentation
-                // and keep it in the list of filtered entry.
+
                 return true;
             }
 
@@ -730,6 +817,10 @@ namespace FourSlash {
                     if (expectedKind) {
                         error += "Expected kind: " + expectedKind + " to equal: " + filterCompletions[0].kind + ".";
                     }
+                    if (replacementSpan) {
+                        const spanText = filterCompletions[0].replacementSpan ? stringify(filterCompletions[0].replacementSpan) : undefined;
+                        error += "Expected replacement span: " + stringify(replacementSpan) + " to equal: " + spanText + ".";
+                    }
                     this.raiseError(error);
                 }
             }
@@ -1561,25 +1652,10 @@ namespace FourSlash {
             this.goToPosition(len);
         }
 
-        public goToDefinition(definitionIndex: number) {
-            const definitions = this.languageService.getDefinitionAtPosition(this.activeFile.fileName, this.currentCaretPosition);
-            if (!definitions || !definitions.length) {
-                this.raiseError("goToDefinition failed - expected to at least one definition location but got 0");
-            }
-
-            if (definitionIndex >= definitions.length) {
-                this.raiseError(`goToDefinition failed - definitionIndex value (${definitionIndex}) exceeds definition list size (${definitions.length})`);
-            }
-
-            const definition = definitions[definitionIndex];
-            this.openFile(definition.fileName);
-            this.currentCaretPosition = definition.textSpan.start;
-        }
-
         public goToTypeDefinition(definitionIndex: number) {
             const definitions = this.languageService.getTypeDefinitionAtPosition(this.activeFile.fileName, this.currentCaretPosition);
             if (!definitions || !definitions.length) {
-                this.raiseError("goToTypeDefinition failed - expected to at least one definition location but got 0");
+                this.raiseError("goToTypeDefinition failed - expected to find at least one definition location but got 0");
             }
 
             if (definitionIndex >= definitions.length) {
@@ -1591,28 +1667,6 @@ namespace FourSlash {
             this.currentCaretPosition = definition.textSpan.start;
         }
 
-        public verifyDefinitionLocationExists(negative: boolean) {
-            const definitions = this.languageService.getDefinitionAtPosition(this.activeFile.fileName, this.currentCaretPosition);
-
-            const foundDefinitions = definitions && definitions.length;
-
-            if (foundDefinitions && negative) {
-                this.raiseError(`goToDefinition - expected to 0 definition locations but got ${definitions.length}`);
-            }
-            else if (!foundDefinitions && !negative) {
-                this.raiseError("goToDefinition - expected to at least one definition location but got 0");
-            }
-        }
-
-        public verifyDefinitionsCount(negative: boolean, expectedCount: number) {
-            const assertFn = negative ? assert.notEqual : assert.equal;
-
-            const definitions = this.languageService.getDefinitionAtPosition(this.activeFile.fileName, this.currentCaretPosition);
-            const actualCount = definitions && definitions.length || 0;
-
-            assertFn(actualCount, expectedCount, this.messageAtLastKnownMarker("Definitions Count"));
-        }
-
         public verifyTypeDefinitionsCount(negative: boolean, expectedCount: number) {
             const assertFn = negative ? assert.notEqual : assert.equal;
 
@@ -1622,18 +1676,12 @@ namespace FourSlash {
             assertFn(actualCount, expectedCount, this.messageAtLastKnownMarker("Type definitions Count"));
         }
 
-        public verifyDefinitionsName(negative: boolean, expectedName: string, expectedContainerName: string) {
+        public verifyGoToDefinitionName(expectedName: string, expectedContainerName: string) {
             const definitions = this.languageService.getDefinitionAtPosition(this.activeFile.fileName, this.currentCaretPosition);
             const actualDefinitionName = definitions && definitions.length ? definitions[0].name : "";
             const actualDefinitionContainerName = definitions && definitions.length ? definitions[0].containerName : "";
-            if (negative) {
-                assert.notEqual(actualDefinitionName, expectedName, this.messageAtLastKnownMarker("Definition Info Name"));
-                assert.notEqual(actualDefinitionContainerName, expectedContainerName, this.messageAtLastKnownMarker("Definition Info Container Name"));
-            }
-            else {
-                assert.equal(actualDefinitionName, expectedName, this.messageAtLastKnownMarker("Definition Info Name"));
-                assert.equal(actualDefinitionContainerName, expectedContainerName, this.messageAtLastKnownMarker("Definition Info Container Name"));
-            }
+            assert.equal(actualDefinitionName, expectedName, this.messageAtLastKnownMarker("Definition Info Name"));
+            assert.equal(actualDefinitionContainerName, expectedContainerName, this.messageAtLastKnownMarker("Definition Info Container Name"));
         }
 
         public getMarkers(): Marker[] {
@@ -1641,6 +1689,10 @@ namespace FourSlash {
             return this.testData.markers.slice(0);
         }
 
+        public getMarkerNames(): string[] {
+            return Object.keys(this.testData.markerPositions);
+        }
+
         public getRanges(): Range[] {
             return this.testData.ranges;
         }
@@ -1649,8 +1701,7 @@ namespace FourSlash {
             const result = ts.createMap<Range[]>();
             for (const range of this.getRanges()) {
                 const text = this.rangeText(range);
-                const ranges = result[text] || (result[text] = []);
-                ranges.push(range);
+                ts.multiMapAdd(result, text, range);
             }
             return result;
         }
@@ -2167,7 +2218,7 @@ namespace FourSlash {
             return text.substring(startPos, endPos);
         }
 
-        private assertItemInCompletionList(items: ts.CompletionEntry[], name: string, text?: string, documentation?: string, kind?: string) {
+        private assertItemInCompletionList(items: ts.CompletionEntry[], name: string, text?: string, documentation?: string, kind?: string, spanIndex?: number) {
             for (let i = 0; i < items.length; i++) {
                 const item = items[i];
                 if (item.name === name) {
@@ -2186,6 +2237,11 @@ namespace FourSlash {
                         assert.equal(item.kind, kind, this.assertionMessageAtLastKnownMarker("completion item kind for " + name));
                     }
 
+                    if (spanIndex !== undefined) {
+                        const span = this.getTextSpanForRangeAtIndex(spanIndex);
+                        assert.isTrue(TestState.textSpansEqual(span, item.replacementSpan), this.assertionMessageAtLastKnownMarker(stringify(span) + " does not equal " + stringify(item.replacementSpan) + " replacement span for " + name));
+                    }
+
                     return;
                 }
             }
@@ -2242,6 +2298,17 @@ namespace FourSlash {
             return `line ${(pos.line + 1)}, col ${pos.character}`;
         }
 
+        private getTextSpanForRangeAtIndex(index: number): ts.TextSpan {
+            const ranges = this.getRanges();
+            if (ranges && ranges.length > index) {
+                const range = ranges[index];
+                return { start: range.start, length: range.end - range.start };
+            }
+            else {
+                this.raiseError("Supplied span index: " + index + " does not exist in range list of size: " + (ranges ? 0 : ranges.length));
+            }
+        }
+
         public getMarkerByName(markerName: string) {
             const markerPos = this.testData.markerPositions[markerName];
             if (markerPos === undefined) {
@@ -2265,6 +2332,10 @@ namespace FourSlash {
         public resetCancelled(): void {
             this.cancellationToken.resetCancelled();
         }
+
+        private static textSpansEqual(a: ts.TextSpan, b: ts.TextSpan) {
+            return a && b && a.start === b.start && a.length === b.length;
+        }
     }
 
     export function runFourSlashTest(basePath: string, testType: FourSlashTestType, fileName: string) {
@@ -2273,12 +2344,16 @@ namespace FourSlash {
     }
 
     export function runFourSlashTestContent(basePath: string, testType: FourSlashTestType, content: string, fileName: string): void {
+        // Give file paths an absolute path for the virtual file system
+        const absoluteBasePath = ts.combinePaths(Harness.virtualFileSystemRoot, basePath);
+        const absoluteFileName = ts.combinePaths(Harness.virtualFileSystemRoot, fileName);
+
         // Parse out the files and their metadata
-        const testData = parseTestData(basePath, content, fileName);
-        const state = new TestState(basePath, testType, testData);
+        const testData = parseTestData(absoluteBasePath, content, absoluteFileName);
+        const state = new TestState(absoluteBasePath, testType, testData);
         const output = ts.transpileModule(content, { reportDiagnostics: true });
         if (output.diagnostics.length > 0) {
-            throw new Error(`Syntax error in ${basePath}: ${output.diagnostics[0].messageText}`);
+            throw new Error(`Syntax error in ${absoluteBasePath}: ${output.diagnostics[0].messageText}`);
         }
         runCode(output.outputText, state);
     }
@@ -2743,6 +2818,10 @@ namespace FourSlashInterface {
             return this.state.getMarkers();
         }
 
+        public markerNames(): string[] {
+            return this.state.getMarkerNames();
+        }
+
         public marker(name?: string): FourSlash.Marker {
             return this.state.getMarkerByName(name);
         }
@@ -2778,10 +2857,6 @@ namespace FourSlashInterface {
             this.state.goToEOF();
         }
 
-        public definition(definitionIndex = 0) {
-            this.state.goToDefinition(definitionIndex);
-        }
-
         public type(definitionIndex = 0) {
             this.state.goToTypeDefinition(definitionIndex);
         }
@@ -2831,12 +2906,12 @@ namespace FourSlashInterface {
 
         // Verifies the completion list contains the specified symbol. The
         // completion list is brought up if necessary
-        public completionListContains(symbol: string, text?: string, documentation?: string, kind?: string) {
+        public completionListContains(symbol: string, text?: string, documentation?: string, kind?: string, spanIndex?: number) {
             if (this.negative) {
-                this.state.verifyCompletionListDoesNotContain(symbol, text, documentation, kind);
+                this.state.verifyCompletionListDoesNotContain(symbol, text, documentation, kind, spanIndex);
             }
             else {
-                this.state.verifyCompletionListContains(symbol, text, documentation, kind);
+                this.state.verifyCompletionListContains(symbol, text, documentation, kind, spanIndex);
             }
         }
 
@@ -2886,22 +2961,10 @@ namespace FourSlashInterface {
             this.state.verifyQuickInfoExists(this.negative);
         }
 
-        public definitionCountIs(expectedCount: number) {
-            this.state.verifyDefinitionsCount(this.negative, expectedCount);
-        }
-
         public typeDefinitionCountIs(expectedCount: number) {
             this.state.verifyTypeDefinitionsCount(this.negative, expectedCount);
         }
 
-        public definitionLocationExists() {
-            this.state.verifyDefinitionLocationExists(this.negative);
-        }
-
-        public verifyDefinitionsName(name: string, containerName: string) {
-            this.state.verifyDefinitionsName(this.negative, name, containerName);
-        }
-
         public isValidBraceCompletionAtPosition(openingBrace: string) {
             this.state.verifyBraceCompletionAtPosition(this.negative, openingBrace);
         }
@@ -2945,6 +3008,25 @@ namespace FourSlashInterface {
             this.state.verifyCurrentFileContent(text);
         }
 
+        public goToDefinitionIs(endMarkers: string | string[]) {
+            this.state.verifyGoToDefinitionIs(endMarkers);
+        }
+
+        public goToDefinition(startMarkerName: string | string[], endMarkerName: string | string[]): void;
+        public goToDefinition(startsAndEnds: [string | string[], string | string[]][]): void;
+        public goToDefinition(startsAndEnds: { [startMarkerName: string]: string | string[] }): void;
+        public goToDefinition(arg0: any, endMarkerName?: string | string[]) {
+            this.state.verifyGoToDefinition(arg0, endMarkerName);
+        }
+
+        public goToDefinitionForMarkers(...markerNames: string[]) {
+            this.state.verifyGoToDefinitionForMarkers(markerNames);
+        }
+
+        public goToDefinitionName(name: string, containerName: string) {
+            this.state.verifyGoToDefinitionName(name, containerName);
+        }
+
         public verifyGetEmitOutputForCurrentFile(expected: string): void {
             this.state.verifyGetEmitOutputForCurrentFile(expected);
         }

src/harness/harness.ts

@@ -416,6 +416,60 @@ namespace Utils {
 
         throw new Error("Could not find child in parent");
     }
+
+    const maxHarnessFrames = 1;
+
+    export function filterStack(error: Error, stackTraceLimit: number = Infinity) {
+        const stack = <string>(<any>error).stack;
+        if (stack) {
+            const lines = stack.split(/\r\n?|\n/g);
+            const filtered: string[] = [];
+            let frameCount = 0;
+            let harnessFrameCount = 0;
+            for (let line of lines) {
+                if (isStackFrame(line)) {
+                    if (frameCount >= stackTraceLimit
+                        || isMocha(line)
+                        || isNode(line)) {
+                        continue;
+                    }
+
+                    if (isHarness(line)) {
+                        if (harnessFrameCount >= maxHarnessFrames) {
+                            continue;
+                        }
+
+                        harnessFrameCount++;
+                    }
+
+                    line = line.replace(/\bfile:\/\/\/(.*?)(?=(:\d+)*($|\)))/, (_, path) => ts.sys.resolvePath(path));
+                    frameCount++;
+                }
+
+                filtered.push(line);
+            }
+
+            (<any>error).stack = filtered.join(Harness.IO.newLine());
+        }
+
+        return error;
+    }
+
+    function isStackFrame(line: string) {
+        return /^\s+at\s/.test(line);
+    }
+
+    function isMocha(line: string) {
+        return /[\\/](node_modules|components)[\\/]mocha(js)?[\\/]|[\\/]mocha\.js/.test(line);
+    }
+
+    function isNode(line: string) {
+        return /\((timers|events|node|module)\.js:/.test(line);
+    }
+
+    function isHarness(line: string) {
+        return /[\\/]src[\\/]harness[\\/]|[\\/]run\.js/.test(line);
+    }
 }
 
 namespace Harness.Path {
@@ -452,12 +506,17 @@ namespace Harness {
         getExecutingFilePath(): string;
         exit(exitCode?: number): void;
         readDirectory(path: string, extension?: string[], exclude?: string[], include?: string[]): string[];
+        tryEnableSourceMapsForHost?(): void;
+        getEnvironmentVariable?(name: string): string;
     }
     export var IO: IO;
 
     // harness always uses one kind of new line
     const harnessNewLine = "\r\n";
 
+    // Root for file paths that are stored in a virtual file system
+    export const virtualFileSystemRoot = "/";
+
     namespace IOImpl {
         declare class Enumerator {
             public atEnd(): boolean;
@@ -490,6 +549,7 @@ namespace Harness {
             export const directoryExists: typeof IO.directoryExists = fso.FolderExists;
             export const fileExists: typeof IO.fileExists = fso.FileExists;
             export const log: typeof IO.log = global.WScript && global.WScript.StdOut.WriteLine;
+            export const getEnvironmentVariable: typeof IO.getEnvironmentVariable = name => ts.sys.getEnvironmentVariable(name);
             export const readDirectory: typeof IO.readDirectory = (path, extension, exclude, include) => ts.sys.readDirectory(path, extension, exclude, include);
 
             export function createDirectory(path: string) {
@@ -559,7 +619,13 @@ namespace Harness {
             export const writeFile: typeof IO.writeFile = (path, content) => ts.sys.writeFile(path, content);
             export const fileExists: typeof IO.fileExists = fs.existsSync;
             export const log: typeof IO.log = s => console.log(s);
+            export const getEnvironmentVariable: typeof IO.getEnvironmentVariable = name => ts.sys.getEnvironmentVariable(name);
 
+            export function tryEnableSourceMapsForHost() {
+                if (ts.sys.tryEnableSourceMapsForHost) {
+                    ts.sys.tryEnableSourceMapsForHost();
+                }
+            }
             export const readDirectory: typeof IO.readDirectory = (path, extension, exclude, include) => ts.sys.readDirectory(path, extension, exclude, include);
 
             export function createDirectory(path: string) {
@@ -710,7 +776,16 @@ namespace Harness {
                 return dirPath;
             }
             export let directoryName: typeof IO.directoryName = Utils.memoize(directoryNameImpl);
-            export const resolvePath = (path: string) => directoryName(path);
+
+            export function resolvePath(path: string) {
+                const response = Http.getFileFromServerSync(serverRoot + path + "?resolve=true");
+                if (response.status === 200) {
+                    return response.responseText;
+                }
+                else {
+                    return undefined;
+                }
+            }
 
             export function fileExists(path: string): boolean {
                 const response = Http.getFileFromServerSync(serverRoot + path);
@@ -784,7 +859,9 @@ namespace Harness {
 namespace Harness {
     export const libFolder = "built/local/";
     const tcServicesFileName = ts.combinePaths(libFolder, Utils.getExecutionEnvironment() === Utils.ExecutionEnvironment.Browser ? "typescriptServicesInBrowserTest.js" : "typescriptServices.js");
-    export const tcServicesFile = IO.readFile(tcServicesFileName);
+    export const tcServicesFile = IO.readFile(tcServicesFileName) + (Utils.getExecutionEnvironment() !== Utils.ExecutionEnvironment.Browser
+        ? IO.newLine() + `//# sourceURL=${IO.resolvePath(tcServicesFileName)}`
+        : "");
 
     export interface SourceMapEmitterCallback {
         (emittedFile: string, emittedLine: number, emittedColumn: number, sourceFile: string, sourceLine: number, sourceColumn: number, sourceName: string): void;
@@ -1481,7 +1558,7 @@ namespace Harness {
                 }
 
                 Harness.Baseline.runBaseline(baselinePath.replace(/\.tsx?/, ".js.map"), () => {
-                    if (options.noEmitOnError && result.errors.length !== 0 && result.sourceMaps.length === 0) {
+                    if ((options.noEmitOnError && result.errors.length !== 0) || result.sourceMaps.length === 0) {
                         // We need to return null here or the runBaseLine will actually create a empty file.
                         // Baselining isn't required here because there is no output.
                         /* tslint:disable:no-null-keyword */
@@ -1648,7 +1725,7 @@ namespace Harness {
             }
 
             public getSourceMapRecord() {
-                if (this.sourceMapData) {
+                if (this.sourceMapData && this.sourceMapData.length > 0) {
                     return Harness.SourceMapRecorder.getSourceMapRecord(this.sourceMapData, this.program, this.files);
                 }
             }
@@ -1785,7 +1862,7 @@ namespace Harness {
                     tsConfig.options.configFilePath = data.name;
 
                     // delete entry from the list
-                    testUnitData.splice(i, 1);
+                    ts.orderedRemoveItemAt(testUnitData, i);
 
                     break;
                 }
@@ -1905,9 +1982,7 @@ namespace Harness {
         }
 
         export function runBaseline(relativeFileName: string, generateContent: () => string, opts?: BaselineOptions): void {
-
             const actualFileName = localPath(relativeFileName, opts && opts.Baselinefolder, opts && opts.Subfolder);
-
             const actual = generateActual(generateContent);
             const comparison = compareToBaseline(actual, relativeFileName, opts);
             writeComparison(comparison.expected, comparison.actual, relativeFileName, actualFileName);

src/harness/harnessLanguageService.ts

@@ -123,7 +123,7 @@ namespace Harness.LanguageService {
     }
 
     export class LanguageServiceAdapterHost {
-        protected fileNameToScript = ts.createMap<ScriptInfo>();
+        protected virtualFileSystem: Utils.VirtualFileSystem = new Utils.VirtualFileSystem(virtualFileSystemRoot, /*useCaseSensitiveFilenames*/false);
 
         constructor(protected cancellationToken = DefaultHostCancellationToken.Instance,
                     protected settings = ts.getDefaultCompilerOptions()) {
@@ -135,22 +135,24 @@ namespace Harness.LanguageService {
 
         public getFilenames(): string[] {
             const fileNames: string[] = [];
-            ts.forEachProperty(this.fileNameToScript, (scriptInfo) => {
+            for (const virtualEntry of this.virtualFileSystem.getAllFileEntries()){
+                const scriptInfo = virtualEntry.content;
                 if (scriptInfo.isRootFile) {
                     // only include root files here
                     // usually it means that we won't include lib.d.ts in the list of root files so it won't mess the computation of compilation root dir.
                     fileNames.push(scriptInfo.fileName);
                 }
-            });
+            }
             return fileNames;
         }
 
         public getScriptInfo(fileName: string): ScriptInfo {
-            return this.fileNameToScript[fileName];
+            const fileEntry = this.virtualFileSystem.traversePath(fileName);
+            return fileEntry && fileEntry.isFile() ? (<Utils.VirtualFile>fileEntry).content : undefined;
         }
 
         public addScript(fileName: string, content: string, isRootFile: boolean): void {
-            this.fileNameToScript[fileName] = new ScriptInfo(fileName, content, isRootFile);
+            this.virtualFileSystem.addFile(fileName, new ScriptInfo(fileName, content, isRootFile));
         }
 
         public editScript(fileName: string, start: number, end: number, newText: string) {
@@ -171,7 +173,7 @@ namespace Harness.LanguageService {
           * @param col 0 based index
           */
         public positionToLineAndCharacter(fileName: string, position: number): ts.LineAndCharacter {
-            const script: ScriptInfo = this.fileNameToScript[fileName];
+            const script: ScriptInfo = this.getScriptInfo(fileName);
             assert.isOk(script);
 
             return ts.computeLineAndCharacterOfPosition(script.getLineMap(), position);
@@ -182,8 +184,14 @@ namespace Harness.LanguageService {
     class NativeLanguageServiceHost extends LanguageServiceAdapterHost implements ts.LanguageServiceHost {
         getCompilationSettings() { return this.settings; }
         getCancellationToken() { return this.cancellationToken; }
-        getDirectories(path: string): string[] { return []; }
-        getCurrentDirectory(): string { return ""; }
+        getDirectories(path: string): string[] {
+            const dir = this.virtualFileSystem.traversePath(path);
+            if (dir && dir.isDirectory()) {
+                return ts.map((<Utils.VirtualDirectory>dir).getDirectories(), (d) => ts.combinePaths(path, d.name));
+            }
+            return [];
+        }
+        getCurrentDirectory(): string { return virtualFileSystemRoot; }
         getDefaultLibFileName(): string { return Harness.Compiler.defaultLibFileName; }
         getScriptFileNames(): string[] { return this.getFilenames(); }
         getScriptSnapshot(fileName: string): ts.IScriptSnapshot {
@@ -196,6 +204,22 @@ namespace Harness.LanguageService {
             return script ? script.version.toString() : undefined;
         }
 
+        fileExists(fileName: string): boolean {
+            const script = this.getScriptSnapshot(fileName);
+            return script !== undefined;
+        }
+        readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[]): string[] {
+            return ts.matchFiles(path, extensions, exclude, include,
+            /*useCaseSensitiveFileNames*/false,
+            this.getCurrentDirectory(),
+            (p) => this.virtualFileSystem.getAccessibleFileSystemEntries(p));
+        }
+        readFile(path: string, encoding?: string): string {
+            const snapshot = this.getScriptSnapshot(path);
+            return snapshot.getText(0, snapshot.getLength());
+        }
+
+
         log(s: string): void { }
         trace(s: string): void { }
         error(s: string): void { }
@@ -617,6 +641,10 @@ namespace Harness.LanguageService {
             return [];
         }
 
+        getEnvironmentVariable(name: string): string {
+            return ts.sys.getEnvironmentVariable(name);
+        }
+
         readDirectory(path: string, extension?: string[], exclude?: string[], include?: string[]): string[] {
             throw new Error("Not implemented Yet.");
         }

src/harness/projectsRunner.ts

@@ -473,7 +473,6 @@ class ProjectRunner extends RunnerBase {
                         }
                     });
 
-
                     it("Baseline of emitted result (" + moduleNameToString(moduleKind) + "): " + testCaseFileName, () => {
                         if (testCase.baselineCheck) {
                             const errs: Error[] = [];
@@ -500,18 +499,16 @@ class ProjectRunner extends RunnerBase {
                         }
                     });
 
-
-                    it("SourceMapRecord for (" + moduleNameToString(moduleKind) + "): " + testCaseFileName, () => {
-                        if (compilerResult.sourceMapData) {
-                            Harness.Baseline.runBaseline(getBaselineFolder(compilerResult.moduleKind) + testCaseJustName + ".sourcemap.txt", () => {
-                                return Harness.SourceMapRecorder.getSourceMapRecord(compilerResult.sourceMapData, compilerResult.program,
-                                    ts.filter(compilerResult.outputFiles, outputFile => Harness.Compiler.isJS(outputFile.emittedFileName)));
-                            });
-                        }
-                    });
+                    // it("SourceMapRecord for (" + moduleNameToString(moduleKind) + "): " + testCaseFileName, () => {
+                    //     if (compilerResult.sourceMapData) {
+                    //         Harness.Baseline.runBaseline(getBaselineFolder(compilerResult.moduleKind) + testCaseJustName + ".sourcemap.txt", () => {
+                    //             return Harness.SourceMapRecorder.getSourceMapRecord(compilerResult.sourceMapData, compilerResult.program,
+                    //                 ts.filter(compilerResult.outputFiles, outputFile => Harness.Compiler.isJS(outputFile.emittedFileName)));
+                    //         });
+                    //     }
+                    // });
 
                     // Verify that all the generated .d.ts files compile
-
                     it("Errors in generated Dts files for (" + moduleNameToString(moduleKind) + "): " + testCaseFileName, () => {
                         if (!compilerResult.errors.length && testCase.declaration) {
                             const dTsCompileResult = compileCompileDTsFiles(compilerResult);

src/harness/runner.ts

@@ -82,6 +82,7 @@ interface TestConfig {
     light?: boolean;
     taskConfigsFolder?: string;
     workerCount?: number;
+    stackTraceLimit?: number | "full";
     tasks?: TaskSet[];
     test?: string[];
     runUnitTests?: boolean;
@@ -116,6 +117,13 @@ if (testConfigContent !== "") {
         }
     }
 
+    if (testConfig.stackTraceLimit === "full") {
+        (<any>Error).stackTraceLimit = Infinity;
+    }
+    else if ((+testConfig.stackTraceLimit | 0) > 0) {
+        (<any>Error).stackTraceLimit = testConfig.stackTraceLimit;
+    }
+
     if (testConfig.test && testConfig.test.length > 0) {
         for (const option of testConfig.test) {
             if (!option) {

src/harness/typeWriter.ts

@@ -29,7 +29,7 @@ class TypeWriterWalker {
     }
 
     private visitNode(node: ts.Node): void {
-        if (ts.isExpression(node) || node.kind === ts.SyntaxKind.Identifier) {
+        if (ts.isPartOfExpression(node) || node.kind === ts.SyntaxKind.Identifier) {
             this.logTypeAndSymbol(node);
         }
 

src/harness/unittests/cachingInServerLSHost.ts

@@ -47,6 +47,7 @@ namespace ts {
                 return "";
             },
             getDirectories: (path: string) => [],
+            getEnvironmentVariable: (name: string) => "",
             readDirectory: (path: string, extension?: string[], exclude?: string[], include?: string[]): string[] => {
                 throw new Error("NYI");
             },

src/harness/unittests/session.ts

@@ -18,6 +18,7 @@ namespace ts.server {
         createDirectory(): void {},
         getExecutingFilePath(): string { return void 0; },
         getCurrentDirectory(): string { return void 0; },
+        getEnvironmentVariable(name: string): string { return ""; },
         readDirectory(): string[] { return []; },
         exit(): void { },
         setTimeout(callback, ms, ...args) { return 0; },

src/harness/unittests/transpile.ts

@@ -101,7 +101,6 @@ namespace ts {
                     });
                 });
 
-
                 if (canUseOldTranspile) {
                     it("Correct output (old transpile) for " + justName, () => {
                         Harness.Baseline.runBaseline(justName.replace(/\.tsx?$/, ".oldTranspile.js"), () => {

src/harness/unittests/tsserverProjectSystem.ts

@@ -198,22 +198,12 @@ namespace ts {
 
         watchDirectory(directoryName: string, callback: DirectoryWatcherCallback, recursive: boolean): DirectoryWatcher {
             const path = this.toPath(directoryName);
-            const callbacks = this.watchedDirectories[path] || (this.watchedDirectories[path] = []);
-            callbacks.push({ cb: callback, recursive });
+            const cbWithRecursive = { cb: callback, recursive };
+            multiMapAdd(this.watchedDirectories, path, cbWithRecursive);
             return {
                 referenceCount: 0,
                 directoryName,
-                close: () => {
-                    for (let i = 0; i < callbacks.length; i++) {
-                        if (callbacks[i].cb === callback) {
-                            callbacks.splice(i, 1);
-                            break;
-                        }
-                    }
-                    if (!callbacks.length) {
-                        delete this.watchedDirectories[path];
-                    }
-                }
+                close: () => multiMapRemove(this.watchedDirectories, path, cbWithRecursive)
             };
         }
 
@@ -239,17 +229,8 @@ namespace ts {
 
         watchFile(fileName: string, callback: FileWatcherCallback) {
             const path = this.toPath(fileName);
-            const callbacks = this.watchedFiles[path] || (this.watchedFiles[path] = []);
-            callbacks.push(callback);
-            return {
-                close: () => {
-                    const i = callbacks.indexOf(callback);
-                    callbacks.splice(i, 1);
-                    if (!callbacks.length) {
-                        delete this.watchedFiles[path];
-                    }
-                }
-            };
+            multiMapAdd(this.watchedFiles, path, callback);
+            return { close: () => multiMapRemove(this.watchedFiles, path, callback) };
         }
 
         // TOOD: record and invoke callbacks to simulate timer events
@@ -259,7 +240,7 @@ namespace ts {
         };
         readonly clearTimeout = (timeoutId: any): void => {
             if (typeof timeoutId === "number") {
-                this.callbackQueue.splice(timeoutId, 1);
+                orderedRemoveItemAt(this.callbackQueue, timeoutId);
             }
         };
 
@@ -282,6 +263,8 @@ namespace ts {
         readonly write = (s: string) => notImplemented();
         readonly createDirectory = (s: string) => notImplemented();
         readonly exit = () => notImplemented();
+        readonly getEnvironmentVariable = (s: string) => notImplemented();
+        readonly tryEnableSourceMapsForHost = () => notImplemented();
     }
 
     describe("tsserver-project-system", () => {

src/harness/virtualFileSystem.ts

@@ -16,7 +16,7 @@ namespace Utils {
     }
 
     export class VirtualFile extends VirtualFileSystemEntry {
-        content: string;
+        content?: Harness.LanguageService.ScriptInfo;
         isFile() { return true; }
     }
 
@@ -73,7 +73,7 @@ namespace Utils {
             }
         }
 
-        addFile(name: string, content?: string): VirtualFile {
+        addFile(name: string, content?: Harness.LanguageService.ScriptInfo): VirtualFile {
             const entry = this.getFileSystemEntry(name);
             if (entry === undefined) {
                 const file = new VirtualFile(this.fileSystem, name);
@@ -111,6 +111,7 @@ namespace Utils {
         getFileSystemEntries() { return this.root.getFileSystemEntries(); }
 
         addDirectory(path: string) {
+            path = ts.normalizePath(path);
             const components = ts.getNormalizedPathComponents(path, this.currentDirectory);
             let directory: VirtualDirectory = this.root;
             for (const component of components) {
@@ -123,8 +124,8 @@ namespace Utils {
             return directory;
         }
 
-        addFile(path: string, content?: string) {
-            const absolutePath = ts.getNormalizedAbsolutePath(path, this.currentDirectory);
+        addFile(path: string, content?: Harness.LanguageService.ScriptInfo) {
+            const absolutePath = ts.normalizePath(ts.getNormalizedAbsolutePath(path, this.currentDirectory));
             const fileName = ts.getBaseFileName(path);
             const directoryPath = ts.getDirectoryPath(absolutePath);
             const directory = this.addDirectory(directoryPath);
@@ -141,6 +142,7 @@ namespace Utils {
         }
 
         traversePath(path: string) {
+            path = ts.normalizePath(path);
             let directory: VirtualDirectory = this.root;
             for (const component of ts.getNormalizedPathComponents(path, this.currentDirectory)) {
                 const entry = directory.getFileSystemEntry(component);
@@ -157,6 +159,40 @@ namespace Utils {
 
             return directory;
         }
+
+        /**
+         * Reads the directory at the given path and retrieves a list of file names and a list
+         * of directory names within it. Suitable for use with ts.matchFiles()
+         * @param path  The path to the directory to be read
+         */
+        getAccessibleFileSystemEntries(path: string) {
+            const entry = this.traversePath(path);
+            if (entry && entry.isDirectory()) {
+                const directory = <VirtualDirectory>entry;
+                return {
+                    files: ts.map(directory.getFiles(), f => f.name),
+                    directories: ts.map(directory.getDirectories(), d => d.name)
+                };
+            }
+            return { files: [], directories: [] };
+        }
+
+        getAllFileEntries() {
+            const fileEntries: VirtualFile[] = [];
+            getFilesRecursive(this.root, fileEntries);
+            return fileEntries;
+
+            function getFilesRecursive(dir: VirtualDirectory, result: VirtualFile[]) {
+                const files = dir.getFiles();
+                const dirs = dir.getDirectories();
+                for (const file of files) {
+                    result.push(file);
+                }
+                for (const subDir of dirs) {
+                    getFilesRecursive(subDir, result);
+                }
+            }
+        }
     }
 
     export class MockParseConfigHost extends VirtualFileSystem implements ts.ParseConfigHost {
@@ -170,17 +206,5 @@ namespace Utils {
         readDirectory(path: string, extensions: string[], excludes: string[], includes: string[]) {
             return ts.matchFiles(path, extensions, excludes, includes, this.useCaseSensitiveFileNames, this.currentDirectory, (path: string) => this.getAccessibleFileSystemEntries(path));
         }
-
-        getAccessibleFileSystemEntries(path: string) {
-            const entry = this.traversePath(path);
-            if (entry && entry.isDirectory()) {
-                const directory = <VirtualDirectory>entry;
-                return {
-                    files: ts.map(directory.getFiles(), f => f.name),
-                    directories: ts.map(directory.getDirectories(), d => d.name)
-                };
-            }
-            return { files: [], directories: [] };
-        }
     }
 }

src/lib/es2015.collection.d.ts

@@ -16,7 +16,6 @@ interface MapConstructor {
 declare var Map: MapConstructor;
 
 interface WeakMap<K, V> {
-    clear(): void;
     delete(key: K): boolean;
     get(key: K): V | undefined;
     has(key: K): boolean;
@@ -48,7 +47,6 @@ declare var Set: SetConstructor;
 
 interface WeakSet<T> {
     add(value: T): this;
-    clear(): void;
     delete(value: T): boolean;
     has(value: T): boolean;
 }

src/lib/es5.d.ts

@@ -1060,6 +1060,12 @@ interface ReadonlyArray<T> {
       * @param thisArg An object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
       */
     map<U>(callbackfn: (value: T, index: number, array: ReadonlyArray<T>) => U, thisArg?: any): U[];
+    /**
+     * Returns the elements of an array that meet the condition specified in a callback function.
+     * @param callbackfn A function that accepts up to three arguments. The filter method calls the callbackfn function one time for each element in the array.
+     * @param thisArg An object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
+     */
+    filter<S extends T>(callbackfn: (value: T, index: number, array: ReadonlyArray<T>) => value is S, thisArg?: any): S[];
     /**
       * Returns the elements of an array that meet the condition specified in a callback function.
       * @param callbackfn A function that accepts up to three arguments. The filter method calls the callbackfn function one time for each element in the array.

src/server/client.ts

@@ -216,7 +216,18 @@ namespace ts.server {
             return {
                 isMemberCompletion: false,
                 isNewIdentifierLocation: false,
-                entries: response.body
+                entries: response.body.map(entry => {
+
+                    if (entry.replacementSpan !== undefined) {
+                        const { name, kind, kindModifiers, sortText, replacementSpan} = entry;
+
+                        const convertedSpan = createTextSpanFromBounds(this.lineOffsetToPosition(fileName, replacementSpan.start),
+                            this.lineOffsetToPosition(fileName, replacementSpan.end));
+                        return { name, kind, kindModifiers, sortText, replacementSpan: convertedSpan };
+                    }
+
+                    return entry as { name: string, kind: string, kindModifiers: string, sortText: string };
+                })
             };
         }
 

src/server/editorServices.ts

@@ -275,7 +275,7 @@ namespace ts.server {
         removeRoot(info: ScriptInfo) {
             if (this.filenameToScript.contains(info.path)) {
                 this.filenameToScript.remove(info.path);
-                this.roots = copyListRemovingItem(info, this.roots);
+                unorderedRemoveItem(this.roots, info);
                 this.resolvedModuleNames.remove(info.path);
                 this.resolvedTypeReferenceDirectives.remove(info.path);
             }
@@ -306,11 +306,6 @@ namespace ts.server {
             throw new Error("No script with name '" + filename + "'");
         }
 
-        resolvePath(path: string): string {
-            const result = this.host.resolvePath(path);
-            return result;
-        }
-
         fileExists(path: string): boolean {
             const result = this.host.fileExists(path);
             return result;
@@ -324,6 +319,14 @@ namespace ts.server {
             return this.host.getDirectories(path);
         }
 
+        readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[]): string[] {
+            return this.host.readDirectory(path, extensions, exclude, include);
+        }
+
+        readFile(path: string, encoding?: string): string {
+            return this.host.readFile(path, encoding);
+        }
+
         /**
          *  @param line 1 based index
          */
@@ -585,16 +588,6 @@ namespace ts.server {
         project?: Project;
     }
 
-    function copyListRemovingItem<T>(item: T, list: T[]) {
-        const copiedList: T[] = [];
-        for (let i = 0, len = list.length; i < len; i++) {
-            if (list[i] != item) {
-                copiedList.push(list[i]);
-            }
-        }
-        return copiedList;
-    }
-
     /**
      * This helper funciton processes a list of projects and return the concatenated, sortd and deduplicated output of processing each project.
      */
@@ -880,7 +873,7 @@ namespace ts.server {
                 project.directoryWatcher.close();
                 forEachProperty(project.directoriesWatchedForWildcards, watcher => { watcher.close(); });
                 delete project.directoriesWatchedForWildcards;
-                this.configuredProjects = copyListRemovingItem(project, this.configuredProjects);
+                unorderedRemoveItem(this.configuredProjects, project);
             }
             else {
                 for (const directory of project.directoriesWatchedForTsconfig) {
@@ -892,7 +885,7 @@ namespace ts.server {
                         delete project.projectService.directoryWatchersForTsconfig[directory];
                     }
                 }
-                this.inferredProjects = copyListRemovingItem(project, this.inferredProjects);
+                unorderedRemoveItem(this.inferredProjects, project);
             }
 
             const fileNames = project.getFileNames();
@@ -1017,7 +1010,7 @@ namespace ts.server {
                 }
             }
             else {
-                this.openFilesReferenced = copyListRemovingItem(info, this.openFilesReferenced);
+                unorderedRemoveItem(this.openFilesReferenced, info);
             }
             info.close();
         }
@@ -1524,13 +1517,13 @@ namespace ts.server {
                             // openFileRoots or openFileReferenced.
                             if (info.isOpen) {
                                 if (this.openFileRoots.indexOf(info) >= 0) {
-                                    this.openFileRoots = copyListRemovingItem(info, this.openFileRoots);
+                                    unorderedRemoveItem(this.openFileRoots, info);
                                     if (info.defaultProject && !info.defaultProject.isConfiguredProject()) {
                                         this.removeProject(info.defaultProject);
                                     }
                                 }
                                 if (this.openFilesReferenced.indexOf(info) >= 0) {
-                                    this.openFilesReferenced = copyListRemovingItem(info, this.openFilesReferenced);
+                                    unorderedRemoveItem(this.openFilesReferenced, info);
                                 }
                                 this.openFileRootsConfigured.push(info);
                                 info.defaultProject = project;
@@ -1601,6 +1594,7 @@ namespace ts.server {
                 InsertSpaceAfterFunctionKeywordForAnonymousFunctions: false,
                 InsertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis: false,
                 InsertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets: false,
+                InsertSpaceAfterOpeningAndBeforeClosingNonemptyBraces: true,
                 InsertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces: false,
                 InsertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces: false,
                 PlaceOpenBraceOnNewLineForFunctions: false,

src/server/protocol.d.ts

@@ -773,6 +773,11 @@ declare namespace ts.server.protocol {
          * is often the same as the name but may be different in certain circumstances.
          */
         sortText: string;
+        /**
+         * An optional span that indicates the text to be replaced by this completion item. If present,
+         * this span should be used instead of the default one.
+         */
+        replacementSpan?: TextSpan;
     }
 
     /**

src/server/server.ts

@@ -204,7 +204,7 @@ namespace ts.server {
     // average async stat takes about 30 microseconds
     // set chunk size to do 30 files in < 1 millisecond
     function createPollingWatchedFileSet(interval = 2500, chunkSize = 30) {
-        let watchedFiles: WatchedFile[] = [];
+        const watchedFiles: WatchedFile[] = [];
         let nextFileToCheck = 0;
         let watchTimer: any;
 
@@ -267,7 +267,7 @@ namespace ts.server {
         }
 
         function removeFile(file: WatchedFile) {
-            watchedFiles = copyListRemovingItem(file, watchedFiles);
+            unorderedRemoveItem(watchedFiles, file);
         }
 
         return {

src/server/session.ts

@@ -778,7 +778,17 @@ namespace ts.server {
 
             return completions.entries.reduce((result: protocol.CompletionEntry[], entry: ts.CompletionEntry) => {
                 if (completions.isMemberCompletion || (entry.name.toLowerCase().indexOf(prefix.toLowerCase()) === 0)) {
-                    result.push(entry);
+                    const { name, kind, kindModifiers, sortText, replacementSpan } = entry;
+
+                    let convertedSpan: protocol.TextSpan = undefined;
+                    if (replacementSpan) {
+                        convertedSpan = {
+                            start: compilerService.host.positionToLineOffset(fileName, replacementSpan.start),
+                            end: compilerService.host.positionToLineOffset(fileName, replacementSpan.start + replacementSpan.length)
+                        };
+                    }
+
+                    result.push({ name, kind, kindModifiers, sortText, replacementSpan: convertedSpan });
                 }
                 return result;
             }, []).sort((a, b) => a.name.localeCompare(b.name));

src/services/breakpoints.ts

@@ -56,7 +56,7 @@ namespace ts.BreakpointResolver {
             return spanInNode(otherwiseOnNode);
         }
 
-        function spanInNodeArray<T>(nodeArray: NodeArray<T>) {
+        function spanInNodeArray<T extends Node>(nodeArray: NodeArray<T>) {
             return createTextSpanFromBounds(skipTrivia(sourceFile.text, nodeArray.pos), nodeArray.end);
         }
 
@@ -296,7 +296,7 @@ namespace ts.BreakpointResolver {
                             }
                         }
 
-                        if (isExpression(node)) {
+                        if (isPartOfExpression(node)) {
                             switch (node.parent.kind) {
                                 case SyntaxKind.DoStatement:
                                     // Set span as if on while keyword
@@ -395,7 +395,7 @@ namespace ts.BreakpointResolver {
                 // Breakpoint is possible in variableDeclaration only if there is initialization
                 // or its declaration from 'for of'
                 if (variableDeclaration.initializer ||
-                    (variableDeclaration.flags & NodeFlags.Export) ||
+                    hasModifier(variableDeclaration, ModifierFlags.Export) ||
                     variableDeclaration.parent.parent.kind === SyntaxKind.ForOfStatement) {
                     return textSpanFromVariableDeclaration(variableDeclaration);
                 }
@@ -413,7 +413,7 @@ namespace ts.BreakpointResolver {
             function canHaveSpanInParameterDeclaration(parameter: ParameterDeclaration): boolean {
                 // Breakpoint is possible on parameter only if it has initializer, is a rest parameter, or has public or private modifier
                 return !!parameter.initializer || parameter.dotDotDotToken !== undefined ||
-                    !!(parameter.flags & NodeFlags.Public) || !!(parameter.flags & NodeFlags.Private);
+                    hasModifier(parameter, ModifierFlags.Public | ModifierFlags.Private);
             }
 
             function spanInParameterDeclaration(parameter: ParameterDeclaration): TextSpan {
@@ -439,7 +439,7 @@ namespace ts.BreakpointResolver {
             }
 
             function canFunctionHaveSpanInWholeDeclaration(functionDeclaration: FunctionLikeDeclaration) {
-                return !!(functionDeclaration.flags & NodeFlags.Export) ||
+                return hasModifier(functionDeclaration, ModifierFlags.Export) ||
                     (functionDeclaration.parent.kind === SyntaxKind.ClassDeclaration && functionDeclaration.kind !== SyntaxKind.Constructor);
             }
 

src/services/formatting/rules.ts

@@ -50,6 +50,8 @@ namespace ts.formatting {
         // Insert a space after { and before } in single-line contexts, but remove space from empty object literals {}.
         public SpaceAfterOpenBrace: Rule;
         public SpaceBeforeCloseBrace: Rule;
+        public NoSpaceAfterOpenBrace: Rule;
+        public NoSpaceBeforeCloseBrace: Rule;
         public NoSpaceBetweenEmptyBraceBrackets: Rule;
 
         // Insert new line after { and before } in multi-line contexts.
@@ -287,6 +289,8 @@ namespace ts.formatting {
             // Insert a space after { and before } in single-line contexts, but remove space from empty object literals {}.
             this.SpaceAfterOpenBrace = new Rule(RuleDescriptor.create3(SyntaxKind.OpenBraceToken, Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsSingleLineBlockContext), RuleAction.Space));
             this.SpaceBeforeCloseBrace = new Rule(RuleDescriptor.create2(Shared.TokenRange.Any, SyntaxKind.CloseBraceToken), RuleOperation.create2(new RuleOperationContext(Rules.IsSingleLineBlockContext), RuleAction.Space));
+            this.NoSpaceAfterOpenBrace = new Rule(RuleDescriptor.create3(SyntaxKind.OpenBraceToken, Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsSingleLineBlockContext), RuleAction.Delete));
+            this.NoSpaceBeforeCloseBrace = new Rule(RuleDescriptor.create2(Shared.TokenRange.Any, SyntaxKind.CloseBraceToken), RuleOperation.create2(new RuleOperationContext(Rules.IsSingleLineBlockContext), RuleAction.Delete));
             this.NoSpaceBetweenEmptyBraceBrackets = new Rule(RuleDescriptor.create1(SyntaxKind.OpenBraceToken, SyntaxKind.CloseBraceToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext, Rules.IsObjectContext), RuleAction.Delete));
 
             // Insert new line after { and before } in multi-line contexts.
@@ -414,7 +418,7 @@ namespace ts.formatting {
                 this.SpaceAfterPostdecrementWhenFollowedBySubtract,
                 this.SpaceAfterSubtractWhenFollowedByUnaryMinus, this.SpaceAfterSubtractWhenFollowedByPredecrement,
                 this.NoSpaceAfterCloseBrace,
-                this.SpaceAfterOpenBrace, this.SpaceBeforeCloseBrace, this.NewLineBeforeCloseBraceInBlockContext,
+                this.NewLineBeforeCloseBraceInBlockContext,
                 this.SpaceAfterCloseBrace, this.SpaceBetweenCloseBraceAndElse, this.SpaceBetweenCloseBraceAndWhile, this.NoSpaceBetweenEmptyBraceBrackets,
                 this.NoSpaceBetweenFunctionKeywordAndStar, this.SpaceAfterStarInGeneratorDeclaration,
                 this.SpaceAfterFunctionInFuncDecl, this.NewLineAfterOpenBraceInBlockContext, this.SpaceAfterGetSetInMember,
@@ -789,7 +793,7 @@ namespace ts.formatting {
         }
 
         static NodeIsInDecoratorContext(node: Node): boolean {
-            while (isExpression(node)) {
+            while (isPartOfExpression(node)) {
                 node = node.parent;
             }
             return node.kind === SyntaxKind.Decorator;

src/services/formatting/rulesProvider.ts

@@ -81,6 +81,19 @@ namespace ts.formatting {
                 rules.push(this.globalRules.NoSpaceBetweenBrackets);
             }
 
+            // The default value of InsertSpaceAfterOpeningAndBeforeClosingNonemptyBraces is true
+            // so if the option is undefined, we should treat it as true as well
+            if (options.InsertSpaceAfterOpeningAndBeforeClosingNonemptyBraces !== false) {
+                rules.push(this.globalRules.SpaceAfterOpenBrace);
+                rules.push(this.globalRules.SpaceBeforeCloseBrace);
+                rules.push(this.globalRules.NoSpaceBetweenEmptyBraceBrackets);
+            }
+            else {
+                rules.push(this.globalRules.NoSpaceAfterOpenBrace);
+                rules.push(this.globalRules.NoSpaceBeforeCloseBrace);
+                rules.push(this.globalRules.NoSpaceBetweenEmptyBraceBrackets);
+            }
+
             if (options.InsertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces) {
                 rules.push(this.globalRules.SpaceAfterTemplateHeadAndMiddle);
                 rules.push(this.globalRules.SpaceBeforeTemplateMiddleAndTail);

src/services/formatting/smartIndenter.ts

@@ -208,7 +208,7 @@ namespace ts.formatting {
             // - parent is SourceFile - by default immediate children of SourceFile are not indented except when user indents them manually
             // - parent and child are not on the same line
             const useActualIndentation =
-                (isDeclaration(current) || isStatement(current)) &&
+                (isDeclaration(current) || isStatementButNotDeclaration(current)) &&
                 (parent.kind === SyntaxKind.SourceFile || !parentAndChildShareLine);
 
             if (!useActualIndentation) {

src/services/navigationBar.ts

@@ -397,7 +397,7 @@ namespace ts.NavigationBar {
             case SyntaxKind.FunctionExpression:
             case SyntaxKind.ClassDeclaration:
             case SyntaxKind.ClassExpression:
-                if (node.flags & NodeFlags.Default) {
+                if (getModifierFlags(node) & ModifierFlags.Default) {
                     return "default";
                 }
                 return getFunctionOrClassName(<ArrowFunction | FunctionExpression | ClassExpression>node);
@@ -466,6 +466,7 @@ namespace ts.NavigationBar {
                 case SyntaxKind.MethodDeclaration:
                 case SyntaxKind.GetAccessor:
                 case SyntaxKind.SetAccessor:
+                case SyntaxKind.VariableDeclaration:
                     return hasSomeImportantChild(item);
 
                 case SyntaxKind.ArrowFunction:
@@ -595,7 +596,7 @@ namespace ts.NavigationBar {
             return nodeText((node.parent as PropertyAssignment).name);
         }
         // Default exports are named "default"
-        else if (node.flags & NodeFlags.Default) {
+        else if (getModifierFlags(node) & ModifierFlags.Default) {
             return "default";
         }
         else {

src/services/shims.ts

@@ -67,6 +67,10 @@ namespace ts {
         getProjectVersion?(): string;
         useCaseSensitiveFileNames?(): boolean;
 
+        readDirectory(rootDir: string, extension: string, basePaths?: string, excludeEx?: string, includeFileEx?: string, includeDirEx?: string, depth?: number): string;
+        readFile(path: string, encoding?: string): string;
+        fileExists(path: string): boolean;
+
         getModuleResolutionsForFile?(fileName: string): string;
         getTypeReferenceDirectiveResolutionsForFile?(fileName: string): string;
         directoryExists(directoryName: string): boolean;
@@ -421,6 +425,28 @@ namespace ts {
         public getDefaultLibFileName(options: CompilerOptions): string {
             return this.shimHost.getDefaultLibFileName(JSON.stringify(options));
         }
+
+        public readDirectory(path: string, extensions?: string[], exclude?: string[], include?: string[], depth?: number): string[] {
+            const pattern = getFileMatcherPatterns(path, extensions, exclude, include,
+                this.shimHost.useCaseSensitiveFileNames(), this.shimHost.getCurrentDirectory());
+            return JSON.parse(this.shimHost.readDirectory(
+                path,
+                JSON.stringify(extensions),
+                JSON.stringify(pattern.basePaths),
+                pattern.excludePattern,
+                pattern.includeFilePattern,
+                pattern.includeDirectoryPattern,
+                depth
+            ));
+        }
+
+        public readFile(path: string, encoding?: string): string {
+            return this.shimHost.readFile(path, encoding);
+        }
+
+        public fileExists(path: string): boolean {
+            return this.shimHost.fileExists(path);
+        }
     }
 
     /** A cancellation that throttles calls to the host */

src/services/tsconfig.json

@@ -21,6 +21,19 @@
         "../compiler/utilities.ts",
         "../compiler/binder.ts",
         "../compiler/checker.ts",
+        "../compiler/factory.ts",
+        "../compiler/visitor.ts",
+        "../compiler/transformers/ts.ts",
+        "../compiler/transformers/jsx.ts",
+        "../compiler/transformers/es7.ts",
+        "../compiler/transformers/es6.ts",
+        "../compiler/transformers/generators.ts",
+        "../compiler/transformers/destructuring.ts",
+        "../compiler/transformers/module/module.ts",
+        "../compiler/transformers/module/system.ts",
+        "../compiler/transformers/module/es6.ts",
+        "../compiler/transformer.ts",
+        "../compiler/comments.ts",
         "../compiler/sourcemap.ts",
         "../compiler/declarationEmitter.ts",
         "../compiler/emitter.ts",
@@ -35,6 +48,7 @@
         "services.ts",
         "shims.ts",
         "signatureHelp.ts",
+        "types.ts",
         "utilities.ts",
         "jsTyping.ts",
         "formatting/formatting.ts",

src/services/types.ts

@@ -0,0 +1,830 @@
+namespace ts {
+    export interface Node {
+        getSourceFile(): SourceFile;
+        getChildCount(sourceFile?: SourceFile): number;
+        getChildAt(index: number, sourceFile?: SourceFile): Node;
+        getChildren(sourceFile?: SourceFile): Node[];
+        getStart(sourceFile?: SourceFile, includeJsDocComment?: boolean): number;
+        getFullStart(): number;
+        getEnd(): number;
+        getWidth(sourceFile?: SourceFile): number;
+        getFullWidth(): number;
+        getLeadingTriviaWidth(sourceFile?: SourceFile): number;
+        getFullText(sourceFile?: SourceFile): string;
+        getText(sourceFile?: SourceFile): string;
+        getFirstToken(sourceFile?: SourceFile): Node;
+        getLastToken(sourceFile?: SourceFile): Node;
+    }
+
+    export interface Symbol {
+        getFlags(): SymbolFlags;
+        getName(): string;
+        getDeclarations(): Declaration[];
+        getDocumentationComment(): SymbolDisplayPart[];
+    }
+
+    export interface Type {
+        getFlags(): TypeFlags;
+        getSymbol(): Symbol;
+        getProperties(): Symbol[];
+        getProperty(propertyName: string): Symbol;
+        getApparentProperties(): Symbol[];
+        getCallSignatures(): Signature[];
+        getConstructSignatures(): Signature[];
+        getStringIndexType(): Type;
+        getNumberIndexType(): Type;
+        getBaseTypes(): ObjectType[];
+        getNonNullableType(): Type;
+    }
+
+    export interface Signature {
+        getDeclaration(): SignatureDeclaration;
+        getTypeParameters(): Type[];
+        getParameters(): Symbol[];
+        getReturnType(): Type;
+        getDocumentationComment(): SymbolDisplayPart[];
+    }
+
+    export interface SourceFile {
+        /* @internal */ version: string;
+        /* @internal */ scriptSnapshot: IScriptSnapshot;
+        /* @internal */ nameTable: Map<number>;
+
+        /* @internal */ getNamedDeclarations(): Map<Declaration[]>;
+
+        getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
+        getLineStarts(): number[];
+        getPositionOfLineAndCharacter(line: number, character: number): number;
+        update(newText: string, textChangeRange: TextChangeRange): SourceFile;
+    }
+
+    /**
+     * Represents an immutable snapshot of a script at a specified time.Once acquired, the
+     * snapshot is observably immutable. i.e. the same calls with the same parameters will return
+     * the same values.
+     */
+    export interface IScriptSnapshot {
+        /** Gets a portion of the script snapshot specified by [start, end). */
+        getText(start: number, end: number): string;
+
+        /** Gets the length of this script snapshot. */
+        getLength(): number;
+
+        /**
+         * Gets the TextChangeRange that describe how the text changed between this text and
+         * an older version.  This information is used by the incremental parser to determine
+         * what sections of the script need to be re-parsed.  'undefined' can be returned if the
+         * change range cannot be determined.  However, in that case, incremental parsing will
+         * not happen and the entire document will be re - parsed.
+         */
+        getChangeRange(oldSnapshot: IScriptSnapshot): TextChangeRange | undefined;
+
+        /** Releases all resources held by this script snapshot */
+        dispose?(): void;
+    }
+
+    export namespace ScriptSnapshot {
+        class StringScriptSnapshot implements IScriptSnapshot {
+
+            constructor(private text: string) {
+            }
+
+            public getText(start: number, end: number): string {
+                return this.text.substring(start, end);
+            }
+
+            public getLength(): number {
+                return this.text.length;
+            }
+
+            public getChangeRange(oldSnapshot: IScriptSnapshot): TextChangeRange {
+                // Text-based snapshots do not support incremental parsing. Return undefined
+                // to signal that to the caller.
+                return undefined;
+            }
+        }
+
+        export function fromString(text: string): IScriptSnapshot {
+            return new StringScriptSnapshot(text);
+        }
+    }
+    export interface PreProcessedFileInfo {
+        referencedFiles: FileReference[];
+        typeReferenceDirectives: FileReference[];
+        importedFiles: FileReference[];
+        ambientExternalModules: string[];
+        isLibFile: boolean;
+    }
+
+    export interface HostCancellationToken {
+        isCancellationRequested(): boolean;
+    }
+
+    //
+    // Public interface of the host of a language service instance.
+    //
+    export interface LanguageServiceHost {
+        getCompilationSettings(): CompilerOptions;
+        getNewLine?(): string;
+        getProjectVersion?(): string;
+        getScriptFileNames(): string[];
+        getScriptKind?(fileName: string): ScriptKind;
+        getScriptVersion(fileName: string): string;
+        getScriptSnapshot(fileName: string): IScriptSnapshot | undefined;
+        getLocalizedDiagnosticMessages?(): any;
+        getCancellationToken?(): HostCancellationToken;
+        getCurrentDirectory(): string;
+        getDefaultLibFileName(options: CompilerOptions): string;
+        log?(s: string): void;
+        trace?(s: string): void;
+        error?(s: string): void;
+        useCaseSensitiveFileNames?(): boolean;
+
+        /*
+         * LS host can optionally implement these methods to support completions for module specifiers.
+         * Without these methods, only completions for ambient modules will be provided.
+         */
+        readDirectory?(path: string, extensions?: string[], exclude?: string[], include?: string[]): string[];
+        readFile?(path: string, encoding?: string): string;
+        fileExists?(path: string): boolean;
+
+        /*
+         * LS host can optionally implement this method if it wants to be completely in charge of module name resolution.
+         * if implementation is omitted then language service will use built-in module resolution logic and get answers to
+         * host specific questions using 'getScriptSnapshot'.
+         */
+        resolveModuleNames?(moduleNames: string[], containingFile: string): ResolvedModule[];
+        resolveTypeReferenceDirectives?(typeDirectiveNames: string[], containingFile: string): ResolvedTypeReferenceDirective[];
+        directoryExists?(directoryName: string): boolean;
+
+        /*
+         * getDirectories is also required for full import and type reference completions. Without it defined, certain
+         * completions will not be provided
+         */
+        getDirectories?(directoryName: string): string[];
+    }
+
+    //
+    // Public services of a language service instance associated
+    // with a language service host instance
+    //
+    export interface LanguageService {
+        cleanupSemanticCache(): void;
+
+        getSyntacticDiagnostics(fileName: string): Diagnostic[];
+        getSemanticDiagnostics(fileName: string): Diagnostic[];
+
+        // TODO: Rename this to getProgramDiagnostics to better indicate that these are any
+        // diagnostics present for the program level, and not just 'options' diagnostics.
+        getCompilerOptionsDiagnostics(): Diagnostic[];
+
+        /**
+         * @deprecated Use getEncodedSyntacticClassifications instead.
+         */
+        getSyntacticClassifications(fileName: string, span: TextSpan): ClassifiedSpan[];
+
+        /**
+         * @deprecated Use getEncodedSemanticClassifications instead.
+         */
+        getSemanticClassifications(fileName: string, span: TextSpan): ClassifiedSpan[];
+
+        // Encoded as triples of [start, length, ClassificationType].
+        getEncodedSyntacticClassifications(fileName: string, span: TextSpan): Classifications;
+        getEncodedSemanticClassifications(fileName: string, span: TextSpan): Classifications;
+
+        getCompletionsAtPosition(fileName: string, position: number): CompletionInfo;
+        getCompletionEntryDetails(fileName: string, position: number, entryName: string): CompletionEntryDetails;
+
+        getQuickInfoAtPosition(fileName: string, position: number): QuickInfo;
+
+        getNameOrDottedNameSpan(fileName: string, startPos: number, endPos: number): TextSpan;
+
+        getBreakpointStatementAtPosition(fileName: string, position: number): TextSpan;
+
+        getSignatureHelpItems(fileName: string, position: number): SignatureHelpItems;
+
+        getRenameInfo(fileName: string, position: number): RenameInfo;
+        findRenameLocations(fileName: string, position: number, findInStrings: boolean, findInComments: boolean): RenameLocation[];
+
+        getDefinitionAtPosition(fileName: string, position: number): DefinitionInfo[];
+        getTypeDefinitionAtPosition(fileName: string, position: number): DefinitionInfo[];
+
+        getReferencesAtPosition(fileName: string, position: number): ReferenceEntry[];
+        findReferences(fileName: string, position: number): ReferencedSymbol[];
+        getDocumentHighlights(fileName: string, position: number, filesToSearch: string[]): DocumentHighlights[];
+
+        /** @deprecated */
+        getOccurrencesAtPosition(fileName: string, position: number): ReferenceEntry[];
+
+        getNavigateToItems(searchValue: string, maxResultCount?: number): NavigateToItem[];
+        getNavigationBarItems(fileName: string): NavigationBarItem[];
+
+        getOutliningSpans(fileName: string): OutliningSpan[];
+        getTodoComments(fileName: string, descriptors: TodoCommentDescriptor[]): TodoComment[];
+        getBraceMatchingAtPosition(fileName: string, position: number): TextSpan[];
+        getIndentationAtPosition(fileName: string, position: number, options: EditorOptions): number;
+
+        getFormattingEditsForRange(fileName: string, start: number, end: number, options: FormatCodeOptions): TextChange[];
+        getFormattingEditsForDocument(fileName: string, options: FormatCodeOptions): TextChange[];
+        getFormattingEditsAfterKeystroke(fileName: string, position: number, key: string, options: FormatCodeOptions): TextChange[];
+
+        getDocCommentTemplateAtPosition(fileName: string, position: number): TextInsertion;
+
+        isValidBraceCompletionAtPosition(fileName: string, position: number, openingBrace: number): boolean;
+
+        getEmitOutput(fileName: string): EmitOutput;
+
+        getProgram(): Program;
+
+        /* @internal */ getNonBoundSourceFile(fileName: string): SourceFile;
+
+        dispose(): void;
+    }
+
+    export interface Classifications {
+        spans: number[];
+        endOfLineState: EndOfLineState;
+    }
+
+    export interface ClassifiedSpan {
+        textSpan: TextSpan;
+        classificationType: string; // ClassificationTypeNames
+    }
+
+    export interface NavigationBarItem {
+        text: string;
+        kind: string;
+        kindModifiers: string;
+        spans: TextSpan[];
+        childItems: NavigationBarItem[];
+        indent: number;
+        bolded: boolean;
+        grayed: boolean;
+    }
+
+    export interface TodoCommentDescriptor {
+        text: string;
+        priority: number;
+    }
+
+    export interface TodoComment {
+        descriptor: TodoCommentDescriptor;
+        message: string;
+        position: number;
+    }
+
+    export class TextChange {
+        span: TextSpan;
+        newText: string;
+    }
+
+    export interface TextInsertion {
+        newText: string;
+        /** The position in newText the caret should point to after the insertion. */
+        caretOffset: number;
+    }
+
+    export interface RenameLocation {
+        textSpan: TextSpan;
+        fileName: string;
+    }
+
+    export interface ReferenceEntry {
+        textSpan: TextSpan;
+        fileName: string;
+        isWriteAccess: boolean;
+        isDefinition: boolean;
+    }
+
+    export interface DocumentHighlights {
+        fileName: string;
+        highlightSpans: HighlightSpan[];
+    }
+
+    export namespace HighlightSpanKind {
+        export const none = "none";
+        export const definition = "definition";
+        export const reference = "reference";
+        export const writtenReference = "writtenReference";
+    }
+
+    export interface HighlightSpan {
+        fileName?: string;
+        textSpan: TextSpan;
+        kind: string;
+    }
+
+    export interface NavigateToItem {
+        name: string;
+        kind: string;
+        kindModifiers: string;
+        matchKind: string;
+        isCaseSensitive: boolean;
+        fileName: string;
+        textSpan: TextSpan;
+        containerName: string;
+        containerKind: string;
+    }
+
+    export interface EditorOptions {
+        BaseIndentSize?: number;
+        IndentSize: number;
+        TabSize: number;
+        NewLineCharacter: string;
+        ConvertTabsToSpaces: boolean;
+        IndentStyle: IndentStyle;
+    }
+
+    export enum IndentStyle {
+        None = 0,
+        Block = 1,
+        Smart = 2,
+    }
+
+    export interface FormatCodeOptions extends EditorOptions {
+        InsertSpaceAfterCommaDelimiter: boolean;
+        InsertSpaceAfterSemicolonInForStatements: boolean;
+        InsertSpaceBeforeAndAfterBinaryOperators: boolean;
+        InsertSpaceAfterKeywordsInControlFlowStatements: boolean;
+        InsertSpaceAfterFunctionKeywordForAnonymousFunctions: boolean;
+        InsertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis: boolean;
+        InsertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets: boolean;
+        InsertSpaceAfterOpeningAndBeforeClosingNonemptyBraces?: boolean;
+        InsertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces: boolean;
+        InsertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces?: boolean;
+        PlaceOpenBraceOnNewLineForFunctions: boolean;
+        PlaceOpenBraceOnNewLineForControlBlocks: boolean;
+        [s: string]: boolean | number | string | undefined;
+    }
+
+    export interface DefinitionInfo {
+        fileName: string;
+        textSpan: TextSpan;
+        kind: string;
+        name: string;
+        containerKind: string;
+        containerName: string;
+    }
+
+    export interface ReferencedSymbolDefinitionInfo extends DefinitionInfo {
+        displayParts: SymbolDisplayPart[];
+    }
+
+    export interface ReferencedSymbol {
+        definition: ReferencedSymbolDefinitionInfo;
+        references: ReferenceEntry[];
+    }
+
+    export enum SymbolDisplayPartKind {
+        aliasName,
+        className,
+        enumName,
+        fieldName,
+        interfaceName,
+        keyword,
+        lineBreak,
+        numericLiteral,
+        stringLiteral,
+        localName,
+        methodName,
+        moduleName,
+        operator,
+        parameterName,
+        propertyName,
+        punctuation,
+        space,
+        text,
+        typeParameterName,
+        enumMemberName,
+        functionName,
+        regularExpressionLiteral,
+    }
+
+    export interface SymbolDisplayPart {
+        text: string;
+        kind: string;
+    }
+
+    export interface QuickInfo {
+        kind: string;
+        kindModifiers: string;
+        textSpan: TextSpan;
+        displayParts: SymbolDisplayPart[];
+        documentation: SymbolDisplayPart[];
+    }
+
+    export interface RenameInfo {
+        canRename: boolean;
+        localizedErrorMessage: string;
+        displayName: string;
+        fullDisplayName: string;
+        kind: string;
+        kindModifiers: string;
+        triggerSpan: TextSpan;
+    }
+
+    export interface SignatureHelpParameter {
+        name: string;
+        documentation: SymbolDisplayPart[];
+        displayParts: SymbolDisplayPart[];
+        isOptional: boolean;
+    }
+
+    /**
+     * Represents a single signature to show in signature help.
+     * The id is used for subsequent calls into the language service to ask questions about the
+     * signature help item in the context of any documents that have been updated.  i.e. after
+     * an edit has happened, while signature help is still active, the host can ask important
+     * questions like 'what parameter is the user currently contained within?'.
+     */
+    export interface SignatureHelpItem {
+        isVariadic: boolean;
+        prefixDisplayParts: SymbolDisplayPart[];
+        suffixDisplayParts: SymbolDisplayPart[];
+        separatorDisplayParts: SymbolDisplayPart[];
+        parameters: SignatureHelpParameter[];
+        documentation: SymbolDisplayPart[];
+    }
+
+    /**
+     * Represents a set of signature help items, and the preferred item that should be selected.
+     */
+    export interface SignatureHelpItems {
+        items: SignatureHelpItem[];
+        applicableSpan: TextSpan;
+        selectedItemIndex: number;
+        argumentIndex: number;
+        argumentCount: number;
+    }
+
+    export interface CompletionInfo {
+        isMemberCompletion: boolean;
+        isNewIdentifierLocation: boolean;  // true when the current location also allows for a new identifier
+        entries: CompletionEntry[];
+    }
+
+    export interface CompletionEntry {
+        name: string;
+        kind: string;            // see ScriptElementKind
+        kindModifiers: string;   // see ScriptElementKindModifier, comma separated
+        sortText: string;
+        /**
+          * An optional span that indicates the text to be replaced by this completion item. It will be
+          * set if the required span differs from the one generated by the default replacement behavior and should
+          * be used in that case
+          */
+        replacementSpan?: TextSpan;
+    }
+
+    export interface CompletionEntryDetails {
+        name: string;
+        kind: string;            // see ScriptElementKind
+        kindModifiers: string;   // see ScriptElementKindModifier, comma separated
+        displayParts: SymbolDisplayPart[];
+        documentation: SymbolDisplayPart[];
+    }
+
+    export interface OutliningSpan {
+        /** The span of the document to actually collapse. */
+        textSpan: TextSpan;
+
+        /** The span of the document to display when the user hovers over the collapsed span. */
+        hintSpan: TextSpan;
+
+        /** The text to display in the editor for the collapsed region. */
+        bannerText: string;
+
+        /**
+          * Whether or not this region should be automatically collapsed when
+          * the 'Collapse to Definitions' command is invoked.
+          */
+        autoCollapse: boolean;
+    }
+
+    export interface EmitOutput {
+        outputFiles: OutputFile[];
+        emitSkipped: boolean;
+    }
+
+    export const enum OutputFileType {
+        JavaScript,
+        SourceMap,
+        Declaration
+    }
+
+    export interface OutputFile {
+        name: string;
+        writeByteOrderMark: boolean;
+        text: string;
+    }
+
+    export const enum EndOfLineState {
+        None,
+        InMultiLineCommentTrivia,
+        InSingleQuoteStringLiteral,
+        InDoubleQuoteStringLiteral,
+        InTemplateHeadOrNoSubstitutionTemplate,
+        InTemplateMiddleOrTail,
+        InTemplateSubstitutionPosition,
+    }
+
+    export enum TokenClass {
+        Punctuation,
+        Keyword,
+        Operator,
+        Comment,
+        Whitespace,
+        Identifier,
+        NumberLiteral,
+        StringLiteral,
+        RegExpLiteral,
+    }
+
+    export interface ClassificationResult {
+        finalLexState: EndOfLineState;
+        entries: ClassificationInfo[];
+    }
+
+    export interface ClassificationInfo {
+        length: number;
+        classification: TokenClass;
+    }
+
+    export interface Classifier {
+        /**
+         * Gives lexical classifications of tokens on a line without any syntactic context.
+         * For instance, a token consisting of the text 'string' can be either an identifier
+         * named 'string' or the keyword 'string', however, because this classifier is not aware,
+         * it relies on certain heuristics to give acceptable results. For classifications where
+         * speed trumps accuracy, this function is preferable; however, for true accuracy, the
+         * syntactic classifier is ideal. In fact, in certain editing scenarios, combining the
+         * lexical, syntactic, and semantic classifiers may issue the best user experience.
+         *
+         * @param text                      The text of a line to classify.
+         * @param lexState                  The state of the lexical classifier at the end of the previous line.
+         * @param syntacticClassifierAbsent Whether the client is *not* using a syntactic classifier.
+         *                                  If there is no syntactic classifier (syntacticClassifierAbsent=true),
+         *                                  certain heuristics may be used in its place; however, if there is a
+         *                                  syntactic classifier (syntacticClassifierAbsent=false), certain
+         *                                  classifications which may be incorrectly categorized will be given
+         *                                  back as Identifiers in order to allow the syntactic classifier to
+         *                                  subsume the classification.
+         * @deprecated Use getLexicalClassifications instead.
+         */
+        getClassificationsForLine(text: string, lexState: EndOfLineState, syntacticClassifierAbsent: boolean): ClassificationResult;
+        getEncodedLexicalClassifications(text: string, endOfLineState: EndOfLineState, syntacticClassifierAbsent: boolean): Classifications;
+    }
+
+    /**
+      * The document registry represents a store of SourceFile objects that can be shared between
+      * multiple LanguageService instances. A LanguageService instance holds on the SourceFile (AST)
+      * of files in the context.
+      * SourceFile objects account for most of the memory usage by the language service. Sharing
+      * the same DocumentRegistry instance between different instances of LanguageService allow
+      * for more efficient memory utilization since all projects will share at least the library
+      * file (lib.d.ts).
+      *
+      * A more advanced use of the document registry is to serialize sourceFile objects to disk
+      * and re-hydrate them when needed.
+      *
+      * To create a default DocumentRegistry, use createDocumentRegistry to create one, and pass it
+      * to all subsequent createLanguageService calls.
+      */
+    export interface DocumentRegistry {
+        /**
+          * Request a stored SourceFile with a given fileName and compilationSettings.
+          * The first call to acquire will call createLanguageServiceSourceFile to generate
+          * the SourceFile if was not found in the registry.
+          *
+          * @param fileName The name of the file requested
+          * @param compilationSettings Some compilation settings like target affects the
+          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
+          * multiple copies of the same file for different compilation settings.
+          * @parm scriptSnapshot Text of the file. Only used if the file was not found
+          * in the registry and a new one was created.
+          * @parm version Current version of the file. Only used if the file was not found
+          * in the registry and a new one was created.
+          */
+        acquireDocument(
+            fileName: string,
+            compilationSettings: CompilerOptions,
+            scriptSnapshot: IScriptSnapshot,
+            version: string,
+            scriptKind?: ScriptKind): SourceFile;
+
+        acquireDocumentWithKey(
+            fileName: string,
+            path: Path,
+            compilationSettings: CompilerOptions,
+            key: DocumentRegistryBucketKey,
+            scriptSnapshot: IScriptSnapshot,
+            version: string,
+            scriptKind?: ScriptKind): SourceFile;
+
+        /**
+          * Request an updated version of an already existing SourceFile with a given fileName
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
+          * to get an updated SourceFile.
+          *
+          * @param fileName The name of the file requested
+          * @param compilationSettings Some compilation settings like target affects the
+          * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
+          * multiple copies of the same file for different compilation settings.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
+          */
+        updateDocument(
+            fileName: string,
+            compilationSettings: CompilerOptions,
+            scriptSnapshot: IScriptSnapshot,
+            version: string,
+            scriptKind?: ScriptKind): SourceFile;
+
+        updateDocumentWithKey(
+            fileName: string,
+            path: Path,
+            compilationSettings: CompilerOptions,
+            key: DocumentRegistryBucketKey,
+            scriptSnapshot: IScriptSnapshot,
+            version: string,
+            scriptKind?: ScriptKind): SourceFile;
+
+        getKeyForCompilationSettings(settings: CompilerOptions): DocumentRegistryBucketKey;
+        /**
+          * Informs the DocumentRegistry that a file is not needed any longer.
+          *
+          * Note: It is not allowed to call release on a SourceFile that was not acquired from
+          * this registry originally.
+          *
+          * @param fileName The name of the file to be released
+          * @param compilationSettings The compilation settings used to acquire the file
+          */
+        releaseDocument(fileName: string, compilationSettings: CompilerOptions): void;
+
+        releaseDocumentWithKey(path: Path, key: DocumentRegistryBucketKey): void;
+
+        reportStats(): string;
+    }
+
+    export type DocumentRegistryBucketKey = string & { __bucketKey: any };
+
+    // TODO: move these to enums
+    export namespace ScriptElementKind {
+        export const unknown = "";
+        export const warning = "warning";
+
+        /** predefined type (void) or keyword (class) */
+        export const keyword = "keyword";
+
+        /** top level script node */
+        export const scriptElement = "script";
+
+        /** module foo {} */
+        export const moduleElement = "module";
+
+        /** class X {} */
+        export const classElement = "class";
+
+        /** var x = class X {} */
+        export const localClassElement = "local class";
+
+        /** interface Y {} */
+        export const interfaceElement = "interface";
+
+        /** type T = ... */
+        export const typeElement = "type";
+
+        /** enum E */
+        export const enumElement = "enum";
+        // TODO: GH#9983
+        export const enumMemberElement = "const";
+
+        /**
+         * Inside module and script only
+         * const v = ..
+         */
+        export const variableElement = "var";
+
+        /** Inside function */
+        export const localVariableElement = "local var";
+
+        /**
+         * Inside module and script only
+         * function f() { }
+         */
+        export const functionElement = "function";
+
+        /** Inside function */
+        export const localFunctionElement = "local function";
+
+        /** class X { [public|private]* foo() {} } */
+        export const memberFunctionElement = "method";
+
+        /** class X { [public|private]* [get|set] foo:number; } */
+        export const memberGetAccessorElement = "getter";
+        export const memberSetAccessorElement = "setter";
+
+        /**
+         * class X { [public|private]* foo:number; }
+         * interface Y { foo:number; }
+         */
+        export const memberVariableElement = "property";
+
+        /** class X { constructor() { } } */
+        export const constructorImplementationElement = "constructor";
+
+        /** interface Y { ():number; } */
+        export const callSignatureElement = "call";
+
+        /** interface Y { []:number; } */
+        export const indexSignatureElement = "index";
+
+        /** interface Y { new():Y; } */
+        export const constructSignatureElement = "construct";
+
+        /** function foo(*Y*: string) */
+        export const parameterElement = "parameter";
+
+        export const typeParameterElement = "type parameter";
+
+        export const primitiveType = "primitive type";
+
+        export const label = "label";
+
+        export const alias = "alias";
+
+        export const constElement = "const";
+
+        export const letElement = "let";
+
+        export const directory = "directory";
+
+        export const externalModuleName = "external module name";
+    }
+
+    export namespace ScriptElementKindModifier {
+        export const none = "";
+        export const publicMemberModifier = "public";
+        export const privateMemberModifier = "private";
+        export const protectedMemberModifier = "protected";
+        export const exportedModifier = "export";
+        export const ambientModifier = "declare";
+        export const staticModifier = "static";
+        export const abstractModifier = "abstract";
+    }
+
+    export class ClassificationTypeNames {
+        public static comment = "comment";
+        public static identifier = "identifier";
+        public static keyword = "keyword";
+        public static numericLiteral = "number";
+        public static operator = "operator";
+        public static stringLiteral = "string";
+        public static whiteSpace = "whitespace";
+        public static text = "text";
+
+        public static punctuation = "punctuation";
+
+        public static className = "class name";
+        public static enumName = "enum name";
+        public static interfaceName = "interface name";
+        public static moduleName = "module name";
+        public static typeParameterName = "type parameter name";
+        public static typeAliasName = "type alias name";
+        public static parameterName = "parameter name";
+        public static docCommentTagName = "doc comment tag name";
+        public static jsxOpenTagName = "jsx open tag name";
+        public static jsxCloseTagName = "jsx close tag name";
+        public static jsxSelfClosingTagName = "jsx self closing tag name";
+        public static jsxAttribute = "jsx attribute";
+        public static jsxText = "jsx text";
+        public static jsxAttributeStringLiteralValue = "jsx attribute string literal value";
+    }
+
+    export const enum ClassificationType {
+        comment = 1,
+        identifier = 2,
+        keyword = 3,
+        numericLiteral = 4,
+        operator = 5,
+        stringLiteral = 6,
+        regularExpressionLiteral = 7,
+        whiteSpace = 8,
+        text = 9,
+        punctuation = 10,
+        className = 11,
+        enumName = 12,
+        interfaceName = 13,
+        moduleName = 14,
+        typeParameterName = 15,
+        typeAliasName = 16,
+        parameterName = 17,
+        docCommentTagName = 18,
+        jsxOpenTagName = 19,
+        jsxCloseTagName = 20,
+        jsxSelfClosingTagName = 21,
+        jsxAttribute = 22,
+        jsxText = 23,
+        jsxAttributeStringLiteralValue = 24,
+    }
+}

src/services/utilities.ts

@@ -1,6 +1,9 @@
 // These utilities are common to multiple language service features.
 /* @internal */
 namespace ts {
+    // Matches the beginning of a triple slash directive
+    const tripleSlashDirectivePrefixRegex = /^\/\/\/\s*</;
+
     export interface ListItemInfo {
         listItemIndex: number;
         list: Node;
@@ -588,15 +591,15 @@ namespace ts {
     }
 
     export function getNodeModifiers(node: Node): string {
-        const flags = getCombinedNodeFlags(node);
+        const flags = getCombinedModifierFlags(node);
         const result: string[] = [];
 
-        if (flags & NodeFlags.Private) result.push(ScriptElementKindModifier.privateMemberModifier);
-        if (flags & NodeFlags.Protected) result.push(ScriptElementKindModifier.protectedMemberModifier);
-        if (flags & NodeFlags.Public) result.push(ScriptElementKindModifier.publicMemberModifier);
-        if (flags & NodeFlags.Static) result.push(ScriptElementKindModifier.staticModifier);
-        if (flags & NodeFlags.Abstract) result.push(ScriptElementKindModifier.abstractModifier);
-        if (flags & NodeFlags.Export) result.push(ScriptElementKindModifier.exportedModifier);
+        if (flags & ModifierFlags.Private) result.push(ScriptElementKindModifier.privateMemberModifier);
+        if (flags & ModifierFlags.Protected) result.push(ScriptElementKindModifier.protectedMemberModifier);
+        if (flags & ModifierFlags.Public) result.push(ScriptElementKindModifier.publicMemberModifier);
+        if (flags & ModifierFlags.Static) result.push(ScriptElementKindModifier.staticModifier);
+        if (flags & ModifierFlags.Abstract) result.push(ScriptElementKindModifier.abstractModifier);
+        if (flags & ModifierFlags.Export) result.push(ScriptElementKindModifier.exportedModifier);
         if (isInAmbientContext(node)) result.push(ScriptElementKindModifier.ambientModifier);
 
         return result.length > 0 ? result.join(",") : ScriptElementKindModifier.none;
@@ -704,6 +707,29 @@ namespace ts {
 
         return false;
     }
+
+    export function hasTrailingDirectorySeparator(path: string) {
+        const lastCharacter = path.charAt(path.length - 1);
+        return lastCharacter === "/" || lastCharacter === "\\";
+    }
+
+    export function isInReferenceComment(sourceFile: SourceFile, position: number): boolean {
+        return isInCommentHelper(sourceFile, position, isReferenceComment);
+
+        function isReferenceComment(c: CommentRange): boolean {
+            const commentText = sourceFile.text.substring(c.pos, c.end);
+            return tripleSlashDirectivePrefixRegex.test(commentText);
+        }
+    }
+
+    export function isInNonReferenceComment(sourceFile: SourceFile, position: number): boolean {
+        return isInCommentHelper(sourceFile, position, isNonReferenceComment);
+
+        function isNonReferenceComment(c: CommentRange): boolean {
+            const commentText = sourceFile.text.substring(c.pos, c.end);
+            return !tripleSlashDirectivePrefixRegex.test(commentText);
+        }
+    }
 }
 
 // Display-part writer helpers

tests/baselines/reference/ClassAndModuleThatMergeWithStaticFunctionAndExportedFunctionThatShareAName.js

@@ -33,8 +33,8 @@ var Point = (function () {
 }());
 var Point;
 (function (Point) {
-    function Origin() { return null; }
-    Point.Origin = Origin; //expected duplicate identifier error
+    function Origin() { return null; } //expected duplicate identifier error
+    Point.Origin = Origin;
 })(Point || (Point = {}));
 var A;
 (function (A) {
@@ -49,7 +49,7 @@ var A;
     A.Point = Point;
     var Point;
     (function (Point) {
-        function Origin() { return ""; }
-        Point.Origin = Origin; //expected duplicate identifier error
+        function Origin() { return ""; } //expected duplicate identifier error
+        Point.Origin = Origin;
     })(Point = A.Point || (A.Point = {}));
 })(A || (A = {}));

tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndExportedVarThatShareAName.js

@@ -28,9 +28,9 @@ var Point = (function () {
         this.x = x;
         this.y = y;
     }
-    Point.Origin = { x: 0, y: 0 };
     return Point;
 }());
+Point.Origin = { x: 0, y: 0 };
 var Point;
 (function (Point) {
     Point.Origin = ""; //expected duplicate identifier error
@@ -42,9 +42,9 @@ var A;
             this.x = x;
             this.y = y;
         }
-        Point.Origin = { x: 0, y: 0 };
         return Point;
     }());
+    Point.Origin = { x: 0, y: 0 };
     A.Point = Point;
     var Point;
     (function (Point) {

tests/baselines/reference/ClassAndModuleThatMergeWithStaticVariableAndNonExportedVarThatShareAName.js

@@ -28,9 +28,9 @@ var Point = (function () {
         this.x = x;
         this.y = y;
     }
-    Point.Origin = { x: 0, y: 0 };
     return Point;
 }());
+Point.Origin = { x: 0, y: 0 };
 var Point;
 (function (Point) {
     var Origin = ""; // not an error, since not exported
@@ -42,9 +42,9 @@ var A;
             this.x = x;
             this.y = y;
         }
-        Point.Origin = { x: 0, y: 0 };
         return Point;
     }());
+    Point.Origin = { x: 0, y: 0 };
     A.Point = Point;
     var Point;
     (function (Point) {

tests/baselines/reference/ClassDeclarationWithInvalidConstOnPropertyDeclaration.js

@@ -7,6 +7,6 @@ class AtomicNumbers {
 var AtomicNumbers = (function () {
     function AtomicNumbers() {
     }
-    AtomicNumbers.H = 1;
     return AtomicNumbers;
 }());
+AtomicNumbers.H = 1;

tests/baselines/reference/ES5For-of1.js.map

@@ -1,2 +1,2 @@
 //// [ES5For-of1.js.map]
-{"version":3,"file":"ES5For-of1.js","sourceRoot":"","sources":["ES5For-of1.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAU,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe,CAAC;IAAzB,IAAI,CAAC,SAAA;IACN,OAAO,CAAC,GAAG,CAAC,CAAC,CAAC,CAAC;CAClB"}
+{"version":3,"file":"ES5For-of1.js","sourceRoot":"","sources":["ES5For-of1.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAU,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe;IAAxB,IAAI,CAAC,SAAA;IACN,OAAO,CAAC,GAAG,CAAC,CAAC,CAAC,CAAC;CAClB"}

tests/baselines/reference/ES5For-of1.sourcemap.txt

@@ -26,7 +26,6 @@ sourceFile:ES5For-of1.ts
 15>                                       ^^^^^^^^^^^^^^
 16>                                                     ^^
 17>                                                       ^^^^
-18>                                                           ^
 1 >
 2 >for
 3 >    
@@ -44,7 +43,6 @@ sourceFile:ES5For-of1.ts
 15>                                       ['a', 'b', 'c']
 16>                                                     
 17>                                                       ['a', 'b', 'c']
-18>                                                           )
 1 >Emitted(1, 1) Source(1, 1) + SourceIndex(0)
 2 >Emitted(1, 4) Source(1, 4) + SourceIndex(0)
 3 >Emitted(1, 5) Source(1, 5) + SourceIndex(0)
@@ -62,7 +60,6 @@ sourceFile:ES5For-of1.ts
 15>Emitted(1, 54) Source(1, 30) + SourceIndex(0)
 16>Emitted(1, 56) Source(1, 15) + SourceIndex(0)
 17>Emitted(1, 60) Source(1, 30) + SourceIndex(0)
-18>Emitted(1, 61) Source(1, 31) + SourceIndex(0)
 ---
 >>>    var v = _a[_i];
 1 >^^^^

tests/baselines/reference/ES5For-of13.js.map

@@ -1,2 +1,2 @@
 //// [ES5For-of13.js.map]
-{"version":3,"file":"ES5For-of13.js","sourceRoot":"","sources":["ES5For-of13.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAU,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe,CAAC;IAAzB,IAAI,CAAC,SAAA;IACN,IAAI,CAAC,GAAG,CAAC,CAAC;CACb"}
+{"version":3,"file":"ES5For-of13.js","sourceRoot":"","sources":["ES5For-of13.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAU,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe;IAAxB,IAAI,CAAC,SAAA;IACN,IAAI,CAAC,GAAG,CAAC,CAAC;CACb"}

tests/baselines/reference/ES5For-of13.sourcemap.txt

@@ -26,7 +26,6 @@ sourceFile:ES5For-of13.ts
 15>                                       ^^^^^^^^^^^^^^
 16>                                                     ^^
 17>                                                       ^^^^
-18>                                                           ^
 1 >
 2 >for
 3 >    
@@ -44,7 +43,6 @@ sourceFile:ES5For-of13.ts
 15>                                       ['a', 'b', 'c']
 16>                                                     
 17>                                                       ['a', 'b', 'c']
-18>                                                           )
 1 >Emitted(1, 1) Source(1, 1) + SourceIndex(0)
 2 >Emitted(1, 4) Source(1, 4) + SourceIndex(0)
 3 >Emitted(1, 5) Source(1, 5) + SourceIndex(0)
@@ -62,7 +60,6 @@ sourceFile:ES5For-of13.ts
 15>Emitted(1, 54) Source(1, 30) + SourceIndex(0)
 16>Emitted(1, 56) Source(1, 15) + SourceIndex(0)
 17>Emitted(1, 60) Source(1, 30) + SourceIndex(0)
-18>Emitted(1, 61) Source(1, 31) + SourceIndex(0)
 ---
 >>>    var v = _a[_i];
 1 >^^^^

tests/baselines/reference/ES5For-of25.js.map

@@ -1,2 +1,2 @@
 //// [ES5For-of25.js.map]
-{"version":3,"file":"ES5For-of25.js","sourceRoot":"","sources":["ES5For-of25.ts"],"names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,CAAC,CAAC,EAAE,CAAC,EAAE,CAAC,CAAC,CAAC;AAClB,GAAG,CAAC,CAAU,UAAC,EAAD,OAAC,EAAD,eAAC,EAAD,IAAC,CAAC;IAAX,IAAI,CAAC,UAAA;IACN,CAAC,CAAC;IACF,CAAC,CAAC;CACL"}
+{"version":3,"file":"ES5For-of25.js","sourceRoot":"","sources":["ES5For-of25.ts"],"names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,CAAC,CAAC,EAAE,CAAC,EAAE,CAAC,CAAC,CAAC;AAClB,GAAG,CAAC,CAAU,UAAC,EAAD,OAAC,EAAD,eAAC,EAAD,IAAC;IAAV,IAAI,CAAC,UAAA;IACN,CAAC,CAAC;IACF,CAAC,CAAC;CACL"}

tests/baselines/reference/ES5For-of25.sourcemap.txt

@@ -59,7 +59,6 @@ sourceFile:ES5For-of25.ts
 9 >                          ^^^^^^^^^^^^^^^
 10>                                         ^^
 11>                                           ^^^^
-12>                                               ^
 1->
   >
 2 >for
@@ -72,7 +71,6 @@ sourceFile:ES5For-of25.ts
 9 >                          a
 10>                                         
 11>                                           a
-12>                                               )
 1->Emitted(2, 1) Source(2, 1) + SourceIndex(0)
 2 >Emitted(2, 4) Source(2, 4) + SourceIndex(0)
 3 >Emitted(2, 5) Source(2, 5) + SourceIndex(0)
@@ -84,7 +82,6 @@ sourceFile:ES5For-of25.ts
 9 >Emitted(2, 42) Source(2, 16) + SourceIndex(0)
 10>Emitted(2, 44) Source(2, 15) + SourceIndex(0)
 11>Emitted(2, 48) Source(2, 16) + SourceIndex(0)
-12>Emitted(2, 49) Source(2, 17) + SourceIndex(0)
 ---
 >>>    var v = a_1[_i];
 1 >^^^^

tests/baselines/reference/ES5For-of26.js.map

@@ -1,2 +1,2 @@
 //// [ES5For-of26.js.map]
-{"version":3,"file":"ES5For-of26.js","sourceRoot":"","sources":["ES5For-of26.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAuB,UAAM,EAAN,MAAC,CAAC,EAAE,CAAC,CAAC,EAAN,cAAM,EAAN,IAAM,CAAC;IAA7B,eAAkB,EAAb,UAAK,EAAL,0BAAK,EAAE,UAAK,EAAL,0BAAK;IAClB,CAAC,CAAC;IACF,CAAC,CAAC;CACL"}
+{"version":3,"file":"ES5For-of26.js","sourceRoot":"","sources":["ES5For-of26.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAuB,UAAM,EAAN,MAAC,CAAC,EAAE,CAAC,CAAC,EAAN,cAAM,EAAN,IAAM;IAAxB,IAAA,WAAc,EAAb,UAAK,EAAL,0BAAK,EAAE,UAAK,EAAL,0BAAK;IAClB,CAAC,CAAC;IACF,CAAC,CAAC;CACL"}

tests/baselines/reference/ES5For-of26.sourcemap.txt

@@ -24,8 +24,7 @@ sourceFile:ES5For-of26.ts
 13>                              ^^^^^^^^^^^^^^
 14>                                            ^^
 15>                                              ^^^^
-16>                                                  ^
-17>                                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
+16>                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
 1 >
 2 >for
 3 >    
@@ -41,7 +40,6 @@ sourceFile:ES5For-of26.ts
 13>                              [2, 3]
 14>                                            
 15>                                              [2, 3]
-16>                                                  )
 1 >Emitted(1, 1) Source(1, 1) + SourceIndex(0)
 2 >Emitted(1, 4) Source(1, 4) + SourceIndex(0)
 3 >Emitted(1, 5) Source(1, 5) + SourceIndex(0)
@@ -57,39 +55,41 @@ sourceFile:ES5For-of26.ts
 13>Emitted(1, 45) Source(1, 34) + SourceIndex(0)
 14>Emitted(1, 47) Source(1, 28) + SourceIndex(0)
 15>Emitted(1, 51) Source(1, 34) + SourceIndex(0)
-16>Emitted(1, 52) Source(1, 35) + SourceIndex(0)
 ---
 >>>    var _b = _a[_i], _c = _b[0], a = _c === void 0 ? 0 : _c, _d = _b[1], b = _d === void 0 ? 1 : _d;
 1->^^^^
-2 >    ^^^^^^^^^^^^^^^
-3 >                   ^^
-4 >                     ^^^^^^^^^^
-5 >                               ^^
-6 >                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^
-7 >                                                           ^^
-8 >                                                             ^^^^^^^^^^
-9 >                                                                       ^^
-10>                                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^
+2 >    ^^^^
+3 >        ^^^^^^^^^^^
+4 >                   ^^
+5 >                     ^^^^^^^^^^
+6 >                               ^^
+7 >                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^
+8 >                                                           ^^
+9 >                                                             ^^^^^^^^^^
+10>                                                                       ^^
+11>                                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^
 1->
-2 >    var [a = 0, b = 1]
-3 >                   
-4 >                     a = 0
-5 >                               
-6 >                                 a = 0
-7 >                                                           , 
-8 >                                                             b = 1
-9 >                                                                       
-10>                                                                         b = 1
-1->Emitted(2, 5) Source(1, 6) + SourceIndex(0)
-2 >Emitted(2, 20) Source(1, 24) + SourceIndex(0)
-3 >Emitted(2, 22) Source(1, 11) + SourceIndex(0)
-4 >Emitted(2, 32) Source(1, 16) + SourceIndex(0)
-5 >Emitted(2, 34) Source(1, 11) + SourceIndex(0)
-6 >Emitted(2, 60) Source(1, 16) + SourceIndex(0)
-7 >Emitted(2, 62) Source(1, 18) + SourceIndex(0)
-8 >Emitted(2, 72) Source(1, 23) + SourceIndex(0)
-9 >Emitted(2, 74) Source(1, 18) + SourceIndex(0)
-10>Emitted(2, 100) Source(1, 23) + SourceIndex(0)
+2 >    
+3 >        [a = 0, b = 1]
+4 >                   
+5 >                     a = 0
+6 >                               
+7 >                                 a = 0
+8 >                                                           , 
+9 >                                                             b = 1
+10>                                                                       
+11>                                                                         b = 1
+1->Emitted(2, 5) Source(1, 10) + SourceIndex(0)
+2 >Emitted(2, 9) Source(1, 10) + SourceIndex(0)
+3 >Emitted(2, 20) Source(1, 24) + SourceIndex(0)
+4 >Emitted(2, 22) Source(1, 11) + SourceIndex(0)
+5 >Emitted(2, 32) Source(1, 16) + SourceIndex(0)
+6 >Emitted(2, 34) Source(1, 11) + SourceIndex(0)
+7 >Emitted(2, 60) Source(1, 16) + SourceIndex(0)
+8 >Emitted(2, 62) Source(1, 18) + SourceIndex(0)
+9 >Emitted(2, 72) Source(1, 23) + SourceIndex(0)
+10>Emitted(2, 74) Source(1, 18) + SourceIndex(0)
+11>Emitted(2, 100) Source(1, 23) + SourceIndex(0)
 ---
 >>>    a;
 1 >^^^^

tests/baselines/reference/ES5For-of3.js.map

@@ -1,2 +1,2 @@
 //// [ES5For-of3.js.map]
-{"version":3,"file":"ES5For-of3.js","sourceRoot":"","sources":["ES5For-of3.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAU,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe,CAAC;IAAzB,IAAI,CAAC,SAAA;IACN,IAAI,CAAC,GAAG,CAAC,CAAC;CAAA"}
+{"version":3,"file":"ES5For-of3.js","sourceRoot":"","sources":["ES5For-of3.ts"],"names":[],"mappings":"AAAA,GAAG,CAAC,CAAU,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe;IAAxB,IAAI,CAAC,SAAA;IACN,IAAI,CAAC,GAAG,CAAC,CAAC;CAAA"}

tests/baselines/reference/ES5For-of3.sourcemap.txt

@@ -26,7 +26,6 @@ sourceFile:ES5For-of3.ts
 15>                                       ^^^^^^^^^^^^^^
 16>                                                     ^^
 17>                                                       ^^^^
-18>                                                           ^
 1 >
 2 >for
 3 >    
@@ -44,7 +43,6 @@ sourceFile:ES5For-of3.ts
 15>                                       ['a', 'b', 'c']
 16>                                                     
 17>                                                       ['a', 'b', 'c']
-18>                                                           )
 1 >Emitted(1, 1) Source(1, 1) + SourceIndex(0)
 2 >Emitted(1, 4) Source(1, 4) + SourceIndex(0)
 3 >Emitted(1, 5) Source(1, 5) + SourceIndex(0)
@@ -62,7 +60,6 @@ sourceFile:ES5For-of3.ts
 15>Emitted(1, 54) Source(1, 30) + SourceIndex(0)
 16>Emitted(1, 56) Source(1, 15) + SourceIndex(0)
 17>Emitted(1, 60) Source(1, 30) + SourceIndex(0)
-18>Emitted(1, 61) Source(1, 31) + SourceIndex(0)
 ---
 >>>    var v = _a[_i];
 1 >^^^^

tests/baselines/reference/ES5For-of8.js.map

@@ -1,2 +1,2 @@
 //// [ES5For-of8.js.map]
-{"version":3,"file":"ES5For-of8.js","sourceRoot":"","sources":["ES5For-of8.ts"],"names":[],"mappings":"AAAA;IACI,MAAM,CAAC,EAAE,CAAC,EAAE,CAAC,EAAE,CAAC;AACpB,CAAC;AACD,GAAG,CAAC,CAAY,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe,CAAC;IAA3B,GAAG,EAAE,CAAC,CAAC,SAAA;IACR,IAAI,CAAC,GAAG,GAAG,EAAE,CAAC,CAAC,CAAC;CACnB"}
+{"version":3,"file":"ES5For-of8.js","sourceRoot":"","sources":["ES5For-of8.ts"],"names":[],"mappings":"AAAA;IACI,MAAM,CAAC,EAAE,CAAC,EAAE,CAAC,EAAE,CAAC;AACpB,CAAC;AACD,GAAG,CAAC,CAAY,UAAe,EAAf,MAAC,GAAG,EAAE,GAAG,EAAE,GAAG,CAAC,EAAf,cAAe,EAAf,IAAe;IAA1B,GAAG,EAAE,CAAC,CAAC,SAAA;IACR,IAAI,CAAC,GAAG,GAAG,EAAE,CAAC,CAAC,CAAC;CACnB"}

tests/baselines/reference/ES5For-of8.sourcemap.txt

@@ -72,7 +72,6 @@ sourceFile:ES5For-of8.ts
 15>                                       ^^^^^^^^^^^^^^
 16>                                                     ^^
 17>                                                       ^^^^
-18>                                                           ^
 1->
   >
 2 >for
@@ -91,7 +90,6 @@ sourceFile:ES5For-of8.ts
 15>                                       ['a', 'b', 'c']
 16>                                                     
 17>                                                       ['a', 'b', 'c']
-18>                                                           )
 1->Emitted(4, 1) Source(4, 1) + SourceIndex(0)
 2 >Emitted(4, 4) Source(4, 4) + SourceIndex(0)
 3 >Emitted(4, 5) Source(4, 5) + SourceIndex(0)
@@ -109,7 +107,6 @@ sourceFile:ES5For-of8.ts
 15>Emitted(4, 54) Source(4, 32) + SourceIndex(0)
 16>Emitted(4, 56) Source(4, 17) + SourceIndex(0)
 17>Emitted(4, 60) Source(4, 32) + SourceIndex(0)
-18>Emitted(4, 61) Source(4, 33) + SourceIndex(0)
 ---
 >>>    foo().x = _a[_i];
 1 >^^^^

tests/baselines/reference/ES5SymbolProperty1.js

@@ -14,7 +14,6 @@ obj[Symbol.foo];
 var Symbol;
 var obj = (_a = {},
     _a[Symbol.foo] = 0,
-    _a
-);
+    _a);
 obj[Symbol.foo];
 var _a;

tests/baselines/reference/FunctionDeclaration10_es6.js

@@ -3,6 +3,9 @@ function * foo(a = yield => yield) {
 }
 
 //// [FunctionDeclaration10_es6.js]
+function* foo(a) {
+    if (a === void 0) { a = yield; }
+}
 yield;
 {
 }

tests/baselines/reference/FunctionDeclaration11_es6.js

@@ -3,5 +3,5 @@ function * yield() {
 }
 
 //// [FunctionDeclaration11_es6.js]
-function yield() {
+function* yield() {
 }

tests/baselines/reference/FunctionDeclaration12_es6.js

@@ -2,4 +2,4 @@
 var v = function * yield() { }
 
 //// [FunctionDeclaration12_es6.js]
-var v = , yield = function () { };
+var v = function* () { }, yield = function () { };

tests/baselines/reference/FunctionDeclaration13_es6.js

@@ -6,7 +6,7 @@ function * foo() {
 
 
 //// [FunctionDeclaration13_es6.js]
-function foo() {
+function* foo() {
     // Legal to use 'yield' in a type context.
     var v;
 }

tests/baselines/reference/FunctionDeclaration1_es6.js

@@ -3,5 +3,5 @@ function * foo() {
 }
 
 //// [FunctionDeclaration1_es6.js]
-function foo() {
+function* foo() {
 }

tests/baselines/reference/FunctionDeclaration5_es6.js

@@ -3,6 +3,7 @@ function*foo(yield) {
 }
 
 //// [FunctionDeclaration5_es6.js]
+function* foo() { }
 yield;
 {
 }

tests/baselines/reference/FunctionDeclaration6_es6.js

@@ -3,6 +3,6 @@ function*foo(a = yield) {
 }
 
 //// [FunctionDeclaration6_es6.js]
-function foo(a) {
+function* foo(a) {
     if (a === void 0) { a = yield; }
 }

tests/baselines/reference/FunctionDeclaration7_es6.js

@@ -6,9 +6,9 @@ function*bar() {
 }
 
 //// [FunctionDeclaration7_es6.js]
-function bar() {
+function* bar() {
     // 'yield' here is an identifier, and not a yield expression.
-    function foo(a) {
+    function* foo(a) {
         if (a === void 0) { a = yield; }
     }
 }

tests/baselines/reference/FunctionDeclaration9_es6.js

@@ -4,7 +4,7 @@ function * foo() {
 }
 
 //// [FunctionDeclaration9_es6.js]
-function foo() {
+function* foo() {
     var v = (_a = {}, _a[yield] = foo, _a);
     var _a;
 }

tests/baselines/reference/FunctionExpression1_es6.js

@@ -2,4 +2,4 @@
 var v = function * () { }
 
 //// [FunctionExpression1_es6.js]
-var v = function () { };
+var v = function* () { };

tests/baselines/reference/FunctionExpression2_es6.js

@@ -2,4 +2,4 @@
 var v = function * foo() { }
 
 //// [FunctionExpression2_es6.js]
-var v = function foo() { };
+var v = function* foo() { };

tests/baselines/reference/FunctionPropertyAssignments1_es6.js

@@ -2,4 +2,4 @@
 var v = { *foo() { } }
 
 //// [FunctionPropertyAssignments1_es6.js]
-var v = { foo: function () { } };
+var v = { foo: function* () { } };