merge conflict

src/compiler/checker.ts

@@ -4612,8 +4612,8 @@ namespace ts {
                     // the modifiers type is T. Otherwise, the modifiers type is {}.
                     const declaredType = <MappedType>getTypeFromMappedTypeNode(type.declaration);
                     const constraint = getConstraintTypeFromMappedType(declaredType);
-                    const extendedConstraint = constraint.flags & TypeFlags.TypeParameter ? getConstraintOfTypeParameter(<TypeParameter>constraint) : constraint;
-                    type.modifiersType = extendedConstraint.flags & TypeFlags.Index ? instantiateType((<IndexType>extendedConstraint).type, type.mapper || identityMapper) : emptyObjectType;
+                    const extendedConstraint = constraint && constraint.flags & TypeFlags.TypeParameter ? getConstraintOfTypeParameter(<TypeParameter>constraint) : constraint;
+                    type.modifiersType = extendedConstraint && extendedConstraint.flags & TypeFlags.Index ? instantiateType((<IndexType>extendedConstraint).type, type.mapper || identityMapper) : emptyObjectType;
                 }
             }
             return type.modifiersType;
@@ -6645,7 +6645,7 @@ namespace ts {
             // Starting with the parent of the symbol's declaration, check if the mapper maps any of
             // the type parameters introduced by enclosing declarations. We just pick the first
             // declaration since multiple declarations will all have the same parent anyway.
-            let node = symbol.declarations[0].parent;
+            let node: Node = symbol.declarations[0];
             while (node) {
                 switch (node.kind) {
                     case SyntaxKind.FunctionType:
@@ -6665,7 +6665,7 @@ namespace ts {
                     case SyntaxKind.ClassExpression:
                     case SyntaxKind.InterfaceDeclaration:
                     case SyntaxKind.TypeAliasDeclaration:
-                        const declaration = <DeclarationWithTypeParameters>node;
+                        const declaration = node as DeclarationWithTypeParameters;
                         if (declaration.typeParameters) {
                             for (const d of declaration.typeParameters) {
                                 if (contains(mappedTypes, getDeclaredTypeOfTypeParameter(getSymbolOfNode(d)))) {
@@ -6680,6 +6680,14 @@ namespace ts {
                             }
                         }
                         break;
+                    case SyntaxKind.JSDocFunctionType:
+                        const func = node as JSDocFunctionType;
+                        for (const p of func.parameters) {
+                            if (contains(mappedTypes, getTypeOfNode(p))) {
+                                return true;
+                            }
+                        }
+                        break;
                     case SyntaxKind.ModuleDeclaration:
                     case SyntaxKind.SourceFile:
                         return false;
@@ -7730,8 +7738,11 @@ namespace ts {
                         }
                     }
                 }
-                else if (relation !== identityRelation && isEmptyObjectType(resolveStructuredTypeMembers(<ObjectType>target))) {
-                    return Ternary.True;
+                else if (relation !== identityRelation) {
+                    const resolved = resolveStructuredTypeMembers(<ObjectType>target);
+                    if (isEmptyObjectType(resolved) || resolved.stringIndexInfo && resolved.stringIndexInfo.type.flags & TypeFlags.Any) {
+                        return Ternary.True;
+                    }
                 }
                 return Ternary.False;
             }
@@ -16888,7 +16899,7 @@ namespace ts {
                     if (!local.isReferenced && !local.exportSymbol) {
                         for (const declaration of local.declarations) {
                             if (!isAmbientModule(declaration)) {
-                                error(declaration.name, Diagnostics._0_is_declared_but_never_used, local.name);
+                                errorUnusedLocal(declaration.name, local.name);
                             }
                         }
                     }
@@ -21845,8 +21856,19 @@ namespace ts {
 
         function checkGrammarNumericLiteral(node: NumericLiteral): boolean {
             // Grammar checking
-            if (node.isOctalLiteral && languageVersion >= ScriptTarget.ES5) {
-                return grammarErrorOnNode(node, Diagnostics.Octal_literals_are_not_available_when_targeting_ECMAScript_5_and_higher);
+            if (node.isOctalLiteral) {
+                let diagnosticMessage: DiagnosticMessage | undefined;
+                if (languageVersion >= ScriptTarget.ES5) {
+                    diagnosticMessage = Diagnostics.Octal_literals_are_not_available_when_targeting_ECMAScript_5_and_higher_Use_the_syntax_0;
+                }
+                else if (isChildOfLiteralType(node)) {
+                    diagnosticMessage = Diagnostics.Octal_literal_types_must_use_ES2015_syntax_Use_the_syntax_0;
+                }
+                if (diagnosticMessage) {
+                    const withMinus = isPrefixUnaryExpression(node.parent) && node.parent.operator === SyntaxKind.MinusToken;
+                    const literal = `${withMinus ? "-" : ""}0o${node.text}`;
+                    return grammarErrorOnNode(withMinus ? node.parent : node, diagnosticMessage, literal);
+                }
             }
         }
 

src/compiler/diagnosticMessages.json

@@ -227,7 +227,7 @@
         "category": "Error",
         "code": 1084
     },
-    "Octal literals are not available when targeting ECMAScript 5 and higher.": {
+    "Octal literals are not available when targeting ECMAScript 5 and higher. Use the syntax '{0}'.": {
         "category": "Error",
         "code": 1085
     },
@@ -2685,6 +2685,10 @@
         "category": "Message",
         "code": 6080
     },
+    "File '{0}' has an unsupported extension, so skipping it.": {
+        "category": "Message",
+        "code": 6081
+    },
     "Only 'amd' and 'system' modules are supported alongside --{0}.": {
         "category": "Error",
         "code": 6082
@@ -2945,6 +2949,10 @@
         "category": "Message",
         "code": 6146
     },
+    "Resolution for module '{0}' was found in cache": {
+        "category": "Message",
+        "code": 6147
+    },
     "Variable '{0}' implicitly has an '{1}' type.": {
         "category": "Error",
         "code": 7005
@@ -3234,5 +3242,9 @@
     "Add {0} to existing import declaration from {1}": {
         "category": "Message",
         "code": 90015
+    },
+    "Octal literal types must use ES2015 syntax. Use the syntax '{0}'.": {
+        "category": "Error",
+        "code": 8017
     }
 }

src/compiler/moduleNameResolver.ts

@@ -47,11 +47,6 @@ namespace ts {
         return resolved.path;
     }
 
-    /** Create Resolved from a file with unknown extension. */
-    function resolvedFromAnyFile(path: string): Resolved | undefined {
-        return { path, extension: extensionFromPath(path) };
-    }
-
     /** Adds `isExernalLibraryImport` to a Resolved to get a ResolvedModule. */
     function resolvedModuleFromResolved({ path, extension }: Resolved, isExternalLibraryImport: boolean): ResolvedModuleFull {
         return { resolvedFileName: path, extension, isExternalLibraryImport };
@@ -71,7 +66,8 @@ namespace ts {
         traceEnabled: boolean;
     }
 
-    function tryReadTypesSection(extensions: Extensions, packageJsonPath: string, baseDirectory: string, state: ModuleResolutionState): string {
+    /** Reads from "main" or "types"/"typings" depending on `extensions`. */
+    function tryReadPackageJsonMainOrTypes(extensions: Extensions, packageJsonPath: string, baseDirectory: string, state: ModuleResolutionState): string {
         const jsonContent = readJson(packageJsonPath, state.host);
 
         switch (extensions) {
@@ -153,6 +149,7 @@ namespace ts {
             if (host.directoryExists(atTypes)) {
                 (typeRoots || (typeRoots = [])).push(atTypes);
             }
+            return undefined;
         });
         return typeRoots;
     }
@@ -241,7 +238,8 @@ namespace ts {
                 if (traceEnabled) {
                     trace(host, Diagnostics.Looking_up_in_node_modules_folder_initial_location_0, initialLocationForSecondaryLookup);
                 }
-                resolvedFile = resolvedTypeScriptOnly(loadModuleFromNodeModules(Extensions.DtsOnly, typeReferenceDirectiveName, initialLocationForSecondaryLookup, failedLookupLocations, moduleResolutionState));
+                const result = loadModuleFromNodeModules(Extensions.DtsOnly, typeReferenceDirectiveName, initialLocationForSecondaryLookup, failedLookupLocations, moduleResolutionState, /*cache*/ undefined);
+                resolvedFile = resolvedTypeScriptOnly(result && result.value);
                 if (!resolvedFile && traceEnabled) {
                     trace(host, Diagnostics.Type_reference_directive_0_was_not_resolved, typeReferenceDirectiveName);
                 }
@@ -293,33 +291,171 @@ namespace ts {
         return result;
     }
 
-    export function resolveModuleName(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost): ResolvedModuleWithFailedLookupLocations {
+    /**
+     * Cached module resolutions per containing directory.
+     * This assumes that any module id will have the same resolution for sibling files located in the same folder.
+     */
+    export interface ModuleResolutionCache extends NonRelativeModuleNameResolutionCache {
+        getOrCreateCacheForDirectory(directoryName: string): Map<ResolvedModuleWithFailedLookupLocations>;
+    }
+
+    /**
+     * Stored map from non-relative module name to a table: directory -> result of module lookup in this directory
+     * We support only non-relative module names because resolution of relative module names is usually more deterministic and thus less expensive.
+     */
+    export interface NonRelativeModuleNameResolutionCache {
+        getOrCreateCacheForModuleName(nonRelativeModuleName: string): PerModuleNameCache;
+    }
+
+    export interface PerModuleNameCache {
+        get(directory: string): ResolvedModuleWithFailedLookupLocations;
+        set(directory: string, result: ResolvedModuleWithFailedLookupLocations): void;
+    }
+
+    export function createModuleResolutionCache(currentDirectory: string, getCanonicalFileName: (s: string) => string): ModuleResolutionCache {
+        const directoryToModuleNameMap = createFileMap<Map<ResolvedModuleWithFailedLookupLocations>>();
+        const moduleNameToDirectoryMap = createMap<PerModuleNameCache>();
+
+        return { getOrCreateCacheForDirectory, getOrCreateCacheForModuleName };
+
+        function getOrCreateCacheForDirectory(directoryName: string) {
+            const path = toPath(directoryName, currentDirectory, getCanonicalFileName);
+            let perFolderCache = directoryToModuleNameMap.get(path);
+            if (!perFolderCache) {
+                perFolderCache = createMap<ResolvedModuleWithFailedLookupLocations>();
+                directoryToModuleNameMap.set(path, perFolderCache);
+            }
+            return perFolderCache;
+        }
+
+        function getOrCreateCacheForModuleName(nonRelativeModuleName: string) {
+            if (!moduleHasNonRelativeName(nonRelativeModuleName)) {
+                return undefined;
+            }
+            let perModuleNameCache = moduleNameToDirectoryMap[nonRelativeModuleName];
+            if (!perModuleNameCache) {
+                moduleNameToDirectoryMap[nonRelativeModuleName] = perModuleNameCache = createPerModuleNameCache();
+            }
+            return perModuleNameCache;
+        }
+
+        function createPerModuleNameCache(): PerModuleNameCache {
+            const directoryPathMap = createFileMap<ResolvedModuleWithFailedLookupLocations>();
+
+            return { get, set };
+
+            function get(directory: string): ResolvedModuleWithFailedLookupLocations {
+                return directoryPathMap.get(toPath(directory, currentDirectory, getCanonicalFileName));
+            }
+
+            /**
+             * At first this function add entry directory -> module resolution result to the table.
+             * Then it computes the set of parent folders for 'directory' that should have the same module resolution result
+             * and for every parent folder in set it adds entry: parent -> module resolution. .
+             * Lets say we first directory name: /a/b/c/d/e and resolution result is: /a/b/bar.ts.
+             * Set of parent folders that should have the same result will be: 
+             * [
+             *     /a/b/c/d, /a/b/c, /a/b
+             * ]
+             * this means that request for module resolution from file in any of these folder will be immediately found in cache.
+             */
+            function set(directory: string, result: ResolvedModuleWithFailedLookupLocations): void {
+                const path = toPath(directory, currentDirectory, getCanonicalFileName);
+                // if entry is already in cache do nothing
+                if (directoryPathMap.contains(path)) {
+                    return;
+                }
+                directoryPathMap.set(path, result);
+
+                const resolvedFileName = result.resolvedModule && result.resolvedModule.resolvedFileName;
+                // find common prefix between directory and resolved file name
+                // this common prefix should be the shorted path that has the same resolution
+                // directory: /a/b/c/d/e
+                // resolvedFileName: /a/b/foo.d.ts
+                const commonPrefix = getCommonPrefix(path, resolvedFileName);
+                let current = path;
+                while (true) {
+                    const parent = getDirectoryPath(current);
+                    if (parent === current || directoryPathMap.contains(parent)) {
+                        break;
+                    }
+                    directoryPathMap.set(parent, result);
+                    current = parent;
+
+                    if (current == commonPrefix) {
+                        break;
+                    }
+                }
+            }
+            
+            function getCommonPrefix(directory: Path, resolution: string) {
+                if (resolution === undefined) {
+                    return undefined;
+                }
+                const resolutionDirectory = toPath(getDirectoryPath(resolution), currentDirectory, getCanonicalFileName);
+
+                // find first position where directory and resolution differs
+                let i = 0;
+                while (i < Math.min(directory.length, resolutionDirectory.length) && directory.charCodeAt(i) === resolutionDirectory.charCodeAt(i)) {
+                    i++;
+                }
+
+                // find last directory separator before position i
+                const sep = directory.lastIndexOf(directorySeparator, i);
+                if (sep < 0) {
+                    return undefined;
+                }
+
+                return directory.substr(0, sep);
+            }
+        }
+    }
+
+    export function resolveModuleName(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: ModuleResolutionCache): ResolvedModuleWithFailedLookupLocations {
         const traceEnabled = isTraceEnabled(compilerOptions, host);
         if (traceEnabled) {
             trace(host, Diagnostics.Resolving_module_0_from_1, moduleName, containingFile);
         }
+        const containingDirectory = getDirectoryPath(containingFile);
+        let perFolderCache = cache && cache.getOrCreateCacheForDirectory(containingDirectory);
+        let result = perFolderCache && perFolderCache[moduleName];
 
-        let moduleResolution = compilerOptions.moduleResolution;
-        if (moduleResolution === undefined) {
-            moduleResolution = getEmitModuleKind(compilerOptions) === ModuleKind.CommonJS ? ModuleResolutionKind.NodeJs : ModuleResolutionKind.Classic;
+        if (result) {
             if (traceEnabled) {
-                trace(host, Diagnostics.Module_resolution_kind_is_not_specified_using_0, ModuleResolutionKind[moduleResolution]);
+                trace(host, Diagnostics.Resolution_for_module_0_was_found_in_cache, moduleName);
             }
         }
         else {
-            if (traceEnabled) {
-                trace(host, Diagnostics.Explicitly_specified_module_resolution_kind_Colon_0, ModuleResolutionKind[moduleResolution]);
+            let moduleResolution = compilerOptions.moduleResolution;
+            if (moduleResolution === undefined) {
+                moduleResolution = getEmitModuleKind(compilerOptions) === ModuleKind.CommonJS ? ModuleResolutionKind.NodeJs : ModuleResolutionKind.Classic;
+                if (traceEnabled) {
+                    trace(host, Diagnostics.Module_resolution_kind_is_not_specified_using_0, ModuleResolutionKind[moduleResolution]);
+                }
+            }
+            else {
+                if (traceEnabled) {
+                    trace(host, Diagnostics.Explicitly_specified_module_resolution_kind_Colon_0, ModuleResolutionKind[moduleResolution]);
+                }
             }
-        }
 
-        let result: ResolvedModuleWithFailedLookupLocations;
-        switch (moduleResolution) {
-            case ModuleResolutionKind.NodeJs:
-                result = nodeModuleNameResolver(moduleName, containingFile, compilerOptions, host);
-                break;
-            case ModuleResolutionKind.Classic:
-                result = classicNameResolver(moduleName, containingFile, compilerOptions, host);
-                break;
+            switch (moduleResolution) {
+                case ModuleResolutionKind.NodeJs:
+                    result = nodeModuleNameResolver(moduleName, containingFile, compilerOptions, host, cache);
+                    break;
+                case ModuleResolutionKind.Classic:
+                    result = classicNameResolver(moduleName, containingFile, compilerOptions, host, cache);
+                    break;
+            }
+
+            if (perFolderCache) {
+                perFolderCache[moduleName] = result;
+                // put result in per-module name cache
+                const perModuleNameCache = cache.getOrCreateCacheForModuleName(moduleName);
+                if (perModuleNameCache) {
+                    perModuleNameCache.set(containingDirectory, result);
+                }
+            }
         }
 
         if (traceEnabled) {
@@ -542,7 +678,7 @@ namespace ts {
         }
     }
 
-    export function nodeModuleNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost): ResolvedModuleWithFailedLookupLocations {
+    export function nodeModuleNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: ModuleResolutionCache): ResolvedModuleWithFailedLookupLocations {
         const containingDirectory = getDirectoryPath(containingFile);
         const traceEnabled = isTraceEnabled(compilerOptions, host);
 
@@ -550,30 +686,30 @@ namespace ts {
         const state: ModuleResolutionState = { compilerOptions, host, traceEnabled };
 
         const result = tryResolve(Extensions.TypeScript) || tryResolve(Extensions.JavaScript);
-        if (result) {
-            const { resolved, isExternalLibraryImport } = result;
+        if (result && result.value) {
+            const { resolved, isExternalLibraryImport } = result.value;
             return createResolvedModuleWithFailedLookupLocations(resolved, isExternalLibraryImport, failedLookupLocations);
         }
         return { resolvedModule: undefined, failedLookupLocations };
 
-        function tryResolve(extensions: Extensions): { resolved: Resolved, isExternalLibraryImport: boolean } | undefined {
+        function tryResolve(extensions: Extensions): SearchResult<{ resolved: Resolved, isExternalLibraryImport: boolean }> {
             const resolved = tryLoadModuleUsingOptionalResolutionSettings(extensions, moduleName, containingDirectory, nodeLoadModuleByRelativeName, failedLookupLocations, state);
             if (resolved) {
-                return { resolved, isExternalLibraryImport: false };
+                return toSearchResult({ resolved, isExternalLibraryImport: false });
             }
 
             if (moduleHasNonRelativeName(moduleName)) {
                 if (traceEnabled) {
                     trace(host, Diagnostics.Loading_module_0_from_node_modules_folder, moduleName);
                 }
-                const resolved = loadModuleFromNodeModules(extensions, moduleName, containingDirectory, failedLookupLocations, state);
+                const resolved = loadModuleFromNodeModules(extensions, moduleName, containingDirectory, failedLookupLocations, state, cache);
                 // For node_modules lookups, get the real path so that multiple accesses to an `npm link`-ed module do not create duplicate files.
-                return resolved && { resolved: { path: realpath(resolved.path, host, traceEnabled), extension: resolved.extension }, isExternalLibraryImport: true };
+                return resolved && { value: resolved.value && { resolved: { path: realpath(resolved.value.path, host, traceEnabled), extension: resolved.value.extension }, isExternalLibraryImport: true } };
             }
             else {
                 const candidate = normalizePath(combinePaths(containingDirectory, moduleName));
                 const resolved = nodeLoadModuleByRelativeName(extensions, candidate, failedLookupLocations, /*onlyRecordFailures*/ false, state);
-                return resolved && { resolved, isExternalLibraryImport: false };
+                return resolved && toSearchResult({ resolved, isExternalLibraryImport: false });
             }
         }
     }
@@ -678,18 +814,21 @@ namespace ts {
             if (state.traceEnabled) {
                 trace(state.host, Diagnostics.Found_package_json_at_0, packageJsonPath);
             }
-            const typesFile = tryReadTypesSection(extensions, packageJsonPath, candidate, state);
-            if (typesFile) {
-                const onlyRecordFailures = !directoryProbablyExists(getDirectoryPath(typesFile), state.host);
+            const mainOrTypesFile = tryReadPackageJsonMainOrTypes(extensions, packageJsonPath, candidate, state);
+            if (mainOrTypesFile) {
+                const onlyRecordFailures = !directoryProbablyExists(getDirectoryPath(mainOrTypesFile), state.host);
                 // A package.json "typings" may specify an exact filename, or may choose to omit an extension.
-                const fromFile = tryFile(typesFile, failedLookupLocations, onlyRecordFailures, state);
-                if (fromFile) {
-                    // Note: this would allow a package.json to specify a ".js" file as typings. Maybe that should be forbidden.
-                    return resolvedFromAnyFile(fromFile);
+                const fromExactFile = tryFile(mainOrTypesFile, failedLookupLocations, onlyRecordFailures, state);
+                if (fromExactFile) {
+                    const resolved = fromExactFile && resolvedIfExtensionMatches(extensions, fromExactFile);
+                    if (resolved) {
+                        return resolved;
+                    }
+                    trace(state.host, Diagnostics.File_0_has_an_unsupported_extension_so_skipping_it, fromExactFile);
                 }
-                const x = tryAddingExtensions(typesFile, Extensions.TypeScript, failedLookupLocations, onlyRecordFailures, state);
-                if (x) {
-                    return x;
+                const resolved = tryAddingExtensions(mainOrTypesFile, Extensions.TypeScript, failedLookupLocations, onlyRecordFailures, state);
+                if (resolved) {
+                    return resolved;
                 }
             }
             else {
@@ -709,6 +848,24 @@ namespace ts {
         return loadModuleFromFile(extensions, combinePaths(candidate, "index"), failedLookupLocations, !directoryExists, state);
     }
 
+    /** Resolve from an arbitrarily specified file. Return `undefined` if it has an unsupported extension. */
+    function resolvedIfExtensionMatches(extensions: Extensions, path: string): Resolved | undefined {
+        const extension = tryGetExtensionFromPath(path);
+        return extension !== undefined && extensionIsOk(extensions, extension) ? { path, extension } : undefined;
+    }
+
+    /** True if `extension` is one of the supported `extensions`. */
+    function extensionIsOk(extensions: Extensions, extension: Extension): boolean {
+        switch (extensions) {
+            case Extensions.JavaScript:
+                return extension === Extension.Js || extension === Extension.Jsx;
+            case Extensions.TypeScript:
+                return extension === Extension.Ts || extension === Extension.Tsx || extension === Extension.Dts;
+            case Extensions.DtsOnly:
+                return extension === Extension.Dts;
+        }
+    }
+
     function pathToPackageJson(directory: string): string {
         return combinePaths(directory, "package.json");
     }
@@ -722,18 +879,23 @@ namespace ts {
             loadNodeModuleFromDirectory(extensions, candidate, failedLookupLocations, !nodeModulesFolderExists, state);
     }
 
-    function loadModuleFromNodeModules(extensions: Extensions, moduleName: string, directory: string, failedLookupLocations: Push<string>, state: ModuleResolutionState): Resolved | undefined {
-        return loadModuleFromNodeModulesWorker(extensions, moduleName, directory, failedLookupLocations, state, /*typesOnly*/ false);
+    function loadModuleFromNodeModules(extensions: Extensions, moduleName: string, directory: string, failedLookupLocations: Push<string>, state: ModuleResolutionState, cache: NonRelativeModuleNameResolutionCache): SearchResult<Resolved> {
+        return loadModuleFromNodeModulesWorker(extensions, moduleName, directory, failedLookupLocations, state, /*typesOnly*/ false, cache);
     }
-    function loadModuleFromNodeModulesAtTypes(moduleName: string, directory: string, failedLookupLocations: Push<string>, state: ModuleResolutionState): Resolved | undefined {
+    function loadModuleFromNodeModulesAtTypes(moduleName: string, directory: string, failedLookupLocations: Push<string>, state: ModuleResolutionState): SearchResult<Resolved> {
         // Extensions parameter here doesn't actually matter, because typesOnly ensures we're just doing @types lookup, which is always DtsOnly.
-        return loadModuleFromNodeModulesWorker(Extensions.DtsOnly, moduleName, directory, failedLookupLocations, state, /*typesOnly*/ true);
+        return loadModuleFromNodeModulesWorker(Extensions.DtsOnly, moduleName, directory, failedLookupLocations, state, /*typesOnly*/ true, /*cache*/ undefined);
     }
 
-    function loadModuleFromNodeModulesWorker(extensions: Extensions, moduleName: string, directory: string, failedLookupLocations: Push<string>, state: ModuleResolutionState, typesOnly: boolean): Resolved | undefined {
+    function loadModuleFromNodeModulesWorker(extensions: Extensions, moduleName: string, directory: string, failedLookupLocations: Push<string>, state: ModuleResolutionState, typesOnly: boolean, cache: NonRelativeModuleNameResolutionCache): SearchResult<Resolved> {
+        const perModuleNameCache = cache && cache.getOrCreateCacheForModuleName(moduleName);
         return forEachAncestorDirectory(normalizeSlashes(directory), ancestorDirectory => {
             if (getBaseFileName(ancestorDirectory) !== "node_modules") {
-                return loadModuleFromNodeModulesOneLevel(extensions, moduleName, ancestorDirectory, failedLookupLocations, state, typesOnly);
+                const resolutionFromCache = tryFindNonRelativeModuleNameInCache(perModuleNameCache, moduleName, ancestorDirectory, state.traceEnabled, state.host);
+                if (resolutionFromCache) {
+                    return resolutionFromCache;
+                }
+                return toSearchResult(loadModuleFromNodeModulesOneLevel(extensions, moduleName, ancestorDirectory, failedLookupLocations, state, typesOnly));
             }
         });
     }
@@ -749,26 +911,41 @@ namespace ts {
         }
     }
 
-    export function classicNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost): ResolvedModuleWithFailedLookupLocations {
+    function tryFindNonRelativeModuleNameInCache(cache: PerModuleNameCache | undefined, moduleName: string, containingDirectory: string, traceEnabled: boolean, host: ModuleResolutionHost): SearchResult<Resolved> {
+        const result = cache && cache.get(containingDirectory);
+        if (result) {
+            if (traceEnabled) {
+                trace(host, Diagnostics.Resolution_for_module_0_was_found_in_cache, moduleName)
+            }
+            return { value: result.resolvedModule && { path: result.resolvedModule.resolvedFileName, extension: result.resolvedModule.extension } };
+        }
+    }
+
+    export function classicNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: NonRelativeModuleNameResolutionCache): ResolvedModuleWithFailedLookupLocations {
         const traceEnabled = isTraceEnabled(compilerOptions, host);
         const state: ModuleResolutionState = { compilerOptions, host, traceEnabled };
         const failedLookupLocations: string[] = [];
         const containingDirectory = getDirectoryPath(containingFile);
 
         const resolved = tryResolve(Extensions.TypeScript) || tryResolve(Extensions.JavaScript);
-        return createResolvedModuleWithFailedLookupLocations(resolved, /*isExternalLibraryImport*/ false, failedLookupLocations);
+        return createResolvedModuleWithFailedLookupLocations(resolved && resolved.value, /*isExternalLibraryImport*/ false, failedLookupLocations);
 
-        function tryResolve(extensions: Extensions): Resolved | undefined {
+        function tryResolve(extensions: Extensions): SearchResult<Resolved> {
             const resolvedUsingSettings = tryLoadModuleUsingOptionalResolutionSettings(extensions, moduleName, containingDirectory, loadModuleFromFile, failedLookupLocations, state);
             if (resolvedUsingSettings) {
-                return resolvedUsingSettings;
+                return { value: resolvedUsingSettings };
             }
+            const perModuleNameCache = cache && cache.getOrCreateCacheForModuleName(moduleName);
 
             if (moduleHasNonRelativeName(moduleName)) {
                 // Climb up parent directories looking for a module.
                 const resolved = forEachAncestorDirectory(containingDirectory, directory => {
+                    const resolutionFromCache = tryFindNonRelativeModuleNameInCache(perModuleNameCache, moduleName, directory, traceEnabled, host);
+                    if (resolutionFromCache) {
+                        return resolutionFromCache;
+                    }
                     const searchName = normalizePath(combinePaths(directory, moduleName));
-                    return loadModuleFromFile(extensions, searchName, failedLookupLocations, /*onlyRecordFailures*/ false, state);
+                    return toSearchResult(loadModuleFromFile(extensions, searchName, failedLookupLocations, /*onlyRecordFailures*/ false, state));
                 });
                 if (resolved) {
                     return resolved;
@@ -780,7 +957,7 @@ namespace ts {
             }
             else {
                 const candidate = normalizePath(combinePaths(containingDirectory, moduleName));
-                return loadModuleFromFile(extensions, candidate, failedLookupLocations, /*onlyRecordFailures*/ false, state);
+                return toSearchResult(loadModuleFromFile(extensions, candidate, failedLookupLocations, /*onlyRecordFailures*/ false, state));
             }
         }
     }
@@ -801,8 +978,28 @@ namespace ts {
         return createResolvedModuleWithFailedLookupLocations(resolved, /*isExternalLibraryImport*/ true, failedLookupLocations);
     }
 
+    /**
+     * Represents result of search. Normally when searching among several alternatives we treat value `undefined` as indicator
+     * that search fails and we should try another option. 
+     * However this does not allow us to represent final result that should be used instead of further searching (i.e. a final result that was found in cache).
+     * SearchResult is used to deal with this issue, its values represents following outcomes:
+     * - undefined - not found, continue searching
+     * - { value: undefined } - not found - stop searching
+     * - { value: <some-value> } - found - stop searching
+     */
+    type SearchResult<T> = { value: T | undefined } | undefined;
+    
+    /**
+     * Wraps value to SearchResult.
+     * @returns undefined if value is undefined or { value } otherwise
+     */
+    function toSearchResult<T>(value: T | undefined): SearchResult<T> {
+        return value !== undefined ? { value } : undefined;
+    }
+
+
     /** Calls `callback` on `directory` and every ancestor directory it has, returning the first defined result. */
-    function forEachAncestorDirectory<T>(directory: string, callback: (directory: string) => T | undefined): T | undefined {
+    function forEachAncestorDirectory<T>(directory: string, callback: (directory: string) => SearchResult<T>): SearchResult<T> {
         while (true) {
             const result = callback(directory);
             if (result !== undefined) {

src/compiler/program.ts

@@ -325,6 +325,7 @@ namespace ts {
         // Map storing if there is emit blocking diagnostics for given input
         const hasEmitBlockingDiagnostics = createFileMap<boolean>(getCanonicalFileName);
 
+        let moduleResolutionCache: ModuleResolutionCache;
         let resolveModuleNamesWorker: (moduleNames: string[], containingFile: string) => ResolvedModuleFull[];
         if (host.resolveModuleNames) {
             resolveModuleNamesWorker = (moduleNames, containingFile) => host.resolveModuleNames(moduleNames, containingFile).map(resolved => {
@@ -338,7 +339,8 @@ namespace ts {
             });
         }
         else {
-            const loader = (moduleName: string, containingFile: string) => resolveModuleName(moduleName, containingFile, options, host).resolvedModule;
+            moduleResolutionCache = createModuleResolutionCache(currentDirectory, x => host.getCanonicalFileName(x));
+            const loader = (moduleName: string, containingFile: string) => resolveModuleName(moduleName, containingFile, options, host, moduleResolutionCache).resolvedModule;
             resolveModuleNamesWorker = (moduleNames, containingFile) => loadWithLocalCache(moduleNames, containingFile, loader);
         }
 
@@ -391,6 +393,9 @@ namespace ts {
             }
         }
 
+        // unconditionally set moduleResolutionCache to undefined to avoid unnecessary leaks
+        moduleResolutionCache = undefined;
+
         // unconditionally set oldProgram to undefined to prevent it from being captured in closure
         oldProgram = undefined;
 

src/compiler/transformers/ts.ts

@@ -1555,12 +1555,15 @@ namespace ts {
             return false;
         }
 
+        type SerializedEntityNameAsExpression = Identifier | BinaryExpression | PropertyAccessExpression;
+        type SerializedTypeNode = SerializedEntityNameAsExpression | VoidExpression | ConditionalExpression;
+
         /**
          * Serializes the type of a node for use with decorator type metadata.
          *
          * @param node The node that should have its type serialized.
          */
-        function serializeTypeOfNode(node: Node): Expression {
+        function serializeTypeOfNode(node: Node): SerializedTypeNode {
             switch (node.kind) {
                 case SyntaxKind.PropertyDeclaration:
                 case SyntaxKind.Parameter:
@@ -1582,7 +1585,7 @@ namespace ts {
          *
          * @param node The node that should have its parameter types serialized.
          */
-        function serializeParameterTypesOfNode(node: Node, container: ClassLikeDeclaration): Expression {
+        function serializeParameterTypesOfNode(node: Node, container: ClassLikeDeclaration): ArrayLiteralExpression {
             const valueDeclaration =
                 isClassLike(node)
                     ? getFirstConstructorWithBody(node)
@@ -1590,7 +1593,7 @@ namespace ts {
                         ? node
                         : undefined;
 
-            const expressions: Expression[] = [];
+            const expressions: SerializedTypeNode[] = [];
             if (valueDeclaration) {
                 const parameters = getParametersOfDecoratedDeclaration(valueDeclaration, container);
                 const numParameters = parameters.length;
@@ -1626,7 +1629,7 @@ namespace ts {
          *
          * @param node The node that should have its return type serialized.
          */
-        function serializeReturnTypeOfNode(node: Node): Expression {
+        function serializeReturnTypeOfNode(node: Node): SerializedTypeNode {
             if (isFunctionLike(node) && node.type) {
                 return serializeTypeNode(node.type);
             }
@@ -1655,13 +1658,16 @@ namespace ts {
          *
          * @param node The type node to serialize.
          */
-        function serializeTypeNode(node: TypeNode): Expression {
+        function serializeTypeNode(node: TypeNode): SerializedTypeNode {
             if (node === undefined) {
                 return createIdentifier("Object");
             }
 
             switch (node.kind) {
                 case SyntaxKind.VoidKeyword:
+                case SyntaxKind.UndefinedKeyword:
+                case SyntaxKind.NullKeyword:
+                case SyntaxKind.NeverKeyword:
                     return createVoidZero();
 
                 case SyntaxKind.ParenthesizedType:
@@ -1713,37 +1719,8 @@ namespace ts {
 
                 case SyntaxKind.IntersectionType:
                 case SyntaxKind.UnionType:
-                    {
-                        const unionOrIntersection = <UnionOrIntersectionTypeNode>node;
-                        let serializedUnion: Identifier;
-                        for (const typeNode of unionOrIntersection.types) {
-                            const serializedIndividual = serializeTypeNode(typeNode) as Identifier;
-                            // Non identifier
-                            if (serializedIndividual.kind !== SyntaxKind.Identifier) {
-                                serializedUnion = undefined;
-                                break;
-                            }
+                    return serializeUnionOrIntersectionType(<UnionOrIntersectionTypeNode>node);
 
-                            // One of the individual is global object, return immediately
-                            if (serializedIndividual.text === "Object") {
-                                return serializedIndividual;
-                            }
-
-                            // Different types
-                            if (serializedUnion && serializedUnion.text !== serializedIndividual.text) {
-                                serializedUnion = undefined;
-                                break;
-                            }
-
-                            serializedUnion = serializedIndividual;
-                        }
-
-                        // If we were able to find common type
-                        if (serializedUnion) {
-                            return serializedUnion;
-                        }
-                    }
-                    // Fallthrough
                 case SyntaxKind.TypeQuery:
                 case SyntaxKind.TypeOperator:
                 case SyntaxKind.IndexedAccessType:
@@ -1761,13 +1738,48 @@ namespace ts {
             return createIdentifier("Object");
         }
 
+        function serializeUnionOrIntersectionType(node: UnionOrIntersectionTypeNode): SerializedTypeNode {
+            let serializedUnion: SerializedTypeNode;
+            for (const typeNode of node.types) {
+                const serializedIndividual = serializeTypeNode(typeNode);
+
+                if (isVoidExpression(serializedIndividual)) {
+                    // If we dont have any other type already set, set the initial type
+                    if (!serializedUnion) {
+                        serializedUnion = serializedIndividual;
+                    }
+                }
+                else if (isIdentifier(serializedIndividual) && serializedIndividual.text === "Object") {
+                    // One of the individual is global object, return immediately
+                    return serializedIndividual;
+                }
+                // If there exists union that is not void 0 expression, check if the the common type is identifier.
+                // anything more complex and we will just default to Object
+                else if (serializedUnion && !isVoidExpression(serializedUnion)) {
+                    // Different types
+                    if (!isIdentifier(serializedUnion) ||
+                        !isIdentifier(serializedIndividual) ||
+                        serializedUnion.text !== serializedIndividual.text) {
+                        return createIdentifier("Object");
+                    }
+                }
+                else {
+                    // Initialize the union type
+                    serializedUnion = serializedIndividual;
+                }
+            }
+
+            // If we were able to find common type, use it
+            return serializedUnion;
+        }
+
         /**
          * Serializes a TypeReferenceNode to an appropriate JS constructor value for use with
          * decorator type metadata.
          *
          * @param node The type reference node.
          */
-        function serializeTypeReferenceNode(node: TypeReferenceNode) {
+        function serializeTypeReferenceNode(node: TypeReferenceNode): SerializedTypeNode {
             switch (resolver.getTypeReferenceSerializationKind(node.typeName, currentScope)) {
                 case TypeReferenceSerializationKind.Unknown:
                     const serialized = serializeEntityNameAsExpression(node.typeName, /*useFallback*/ true);
@@ -1822,7 +1834,7 @@ namespace ts {
          * @param useFallback A value indicating whether to use logical operators to test for the
          *                    entity name at runtime.
          */
-        function serializeEntityNameAsExpression(node: EntityName, useFallback: boolean): Expression {
+        function serializeEntityNameAsExpression(node: EntityName, useFallback: boolean): SerializedEntityNameAsExpression {
             switch (node.kind) {
                 case SyntaxKind.Identifier:
                     // Create a clone of the name with a new parent, and treat it as if it were
@@ -1855,8 +1867,8 @@ namespace ts {
          * @param useFallback A value indicating whether to use logical operators to test for the
          *                    qualified name at runtime.
          */
-        function serializeQualifiedNameAsExpression(node: QualifiedName, useFallback: boolean): Expression {
-            let left: Expression;
+        function serializeQualifiedNameAsExpression(node: QualifiedName, useFallback: boolean): PropertyAccessExpression {
+            let left: SerializedEntityNameAsExpression;
             if (node.left.kind === SyntaxKind.Identifier) {
                 left = serializeEntityNameAsExpression(node.left, useFallback);
             }
@@ -1881,7 +1893,7 @@ namespace ts {
          * Gets an expression that points to the global "Symbol" constructor at runtime if it is
          * available.
          */
-        function getGlobalSymbolNameWithFallback(): Expression {
+        function getGlobalSymbolNameWithFallback(): ConditionalExpression {
             return createConditional(
                 createTypeCheck(createIdentifier("Symbol"), "function"),
                 createIdentifier("Symbol"),
@@ -2719,7 +2731,7 @@ namespace ts {
             let blockLocation: TextRange;
             const body = node.body;
             if (body.kind === SyntaxKind.ModuleBlock) {
-                addRange(statements, visitNodes((<ModuleBlock>body).statements, namespaceElementVisitor, isStatement));
+                saveStateAndInvoke(body, body => addRange(statements, visitNodes((<ModuleBlock>body).statements, namespaceElementVisitor, isStatement)));
                 statementsLocation = (<ModuleBlock>body).statements;
                 blockLocation = body;
             }

src/compiler/utilities.ts

@@ -732,6 +732,20 @@ namespace ts {
         return false;
     }
 
+    export function isChildOfLiteralType(node: Node): boolean {
+        while (node) {
+            if (node.kind === SyntaxKind.LiteralType) {
+                return true;
+            }
+            node = node.parent;
+        }
+        return false;
+    }
+
+    export function isPrefixUnaryExpression(node: Node): node is PrefixUnaryExpression {
+        return node.kind === SyntaxKind.PrefixUnaryExpression;
+    }
+
     // Warning: This has the same semantics as the forEach family of functions,
     //          in that traversal terminates in the event that 'visitor' supplies a truthy value.
     export function forEachReturnStatement<T>(body: Block, visitor: (stmt: ReturnStatement) => T): T {
@@ -3581,6 +3595,10 @@ namespace ts {
         return node.kind === SyntaxKind.Identifier;
     }
 
+    export function isVoidExpression(node: Node): node is VoidExpression {
+        return node.kind === SyntaxKind.VoidExpression;
+    }
+
     export function isGeneratedIdentifier(node: Node): node is GeneratedIdentifier {
         // Using `>` here catches both `GeneratedIdentifierKind.None` and `undefined`.
         return isIdentifier(node) && node.autoGenerateKind > GeneratedIdentifierKind.None;

src/harness/fourslash.ts

@@ -341,6 +341,7 @@ namespace FourSlash {
                 insertSpaceAfterCommaDelimiter: true,
                 insertSpaceAfterSemicolonInForStatements: true,
                 insertSpaceBeforeAndAfterBinaryOperators: true,
+                insertSpaceAfterConstructor: false,
                 insertSpaceAfterKeywordsInControlFlowStatements: true,
                 insertSpaceAfterFunctionKeywordForAnonymousFunctions: false,
                 insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis: false,

src/harness/unittests/tsserverProjectSystem.ts

@@ -1840,6 +1840,41 @@ namespace ts.projectSystem {
             assert.isFalse(service.externalProjects[0].languageServiceEnabled, "language service should be disabled - 2");
         });
 
+        it("files are properly detached when language service is disabled", () => {
+            const f1 = {
+                path: "/a/app.js",
+                content: "var x = 1"
+            };
+            const f2 = {
+                path: "/a/largefile.js",
+                content: ""
+            };
+            const f3 = {
+                path: "/a/lib.js",
+                content: "var x = 1"
+            };
+            const config = {
+                path: "/a/tsconfig.json",
+                content: JSON.stringify({ compilerOptions: { allowJs: true } })
+            };
+            const host = createServerHost([f1, f2, f3, config]);
+            const originalGetFileSize = host.getFileSize;
+            host.getFileSize = (filePath: string) =>
+                filePath === f2.path ? server.maxProgramSizeForNonTsFiles + 1 : originalGetFileSize.call(host, filePath);
+
+            const projectService = createProjectService(host);
+            projectService.openClientFile(f1.path);
+            projectService.checkNumberOfProjects({ configuredProjects: 1 });
+
+            projectService.closeClientFile(f1.path);
+            projectService.checkNumberOfProjects({});
+
+            for (const f of [f2, f3]) {
+                const scriptInfo = projectService.getScriptInfoForNormalizedPath(server.toNormalizedPath(f.path));
+                assert.equal(scriptInfo.containingProjects.length, 0, `expect 0 containing projects for '${f.path}'`)
+            }
+        });
+
         it("language service disabled events are triggered", () => {
             const f1 = {
                 path: "/a/app.js",

src/server/project.ts

@@ -257,8 +257,9 @@ namespace ts.server {
                     info.detachFromProject(this);
                 }
             }
-            else {
-                // release all root files
+            if (!this.program || !this.languageServiceEnabled) {
+                // release all root files either if there is no program or language service is disabled.
+                // in the latter case set of root files can be larger than the set of files in program.
                 for (const root of this.rootFiles) {
                     root.detachFromProject(this);
                 }

src/server/protocol.ts

@@ -2194,12 +2194,14 @@ namespace ts.server.protocol {
         insertSpaceAfterCommaDelimiter?: boolean;
         insertSpaceAfterSemicolonInForStatements?: boolean;
         insertSpaceBeforeAndAfterBinaryOperators?: boolean;
+        insertSpaceAfterConstructor?: boolean;
         insertSpaceAfterKeywordsInControlFlowStatements?: boolean;
         insertSpaceAfterFunctionKeywordForAnonymousFunctions?: boolean;
         insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis?: boolean;
         insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets?: boolean;
         insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces?: boolean;
         insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces?: boolean;
+        insertSpaceBeforeFunctionParenthesis?: boolean;
         placeOpenBraceOnNewLineForFunctions?: boolean;
         placeOpenBraceOnNewLineForControlBlocks?: boolean;
     }

src/server/utilities.ts

@@ -78,6 +78,7 @@ namespace ts.server {
             newLineCharacter: host.newLine || "\n",
             convertTabsToSpaces: true,
             indentStyle: ts.IndentStyle.Smart,
+            insertSpaceAfterConstructor: false,
             insertSpaceAfterCommaDelimiter: true,
             insertSpaceAfterSemicolonInForStatements: true,
             insertSpaceBeforeAndAfterBinaryOperators: true,
@@ -87,6 +88,7 @@ namespace ts.server {
             insertSpaceAfterOpeningAndBeforeClosingNonemptyBrackets: false,
             insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces: false,
             insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces: false,
+            insertSpaceBeforeFunctionParenthesis: false,
             placeOpenBraceOnNewLineForFunctions: false,
             placeOpenBraceOnNewLineForControlBlocks: false,
         };

src/services/formatting/formatting.ts

@@ -488,8 +488,6 @@ namespace ts.formatting {
                         // open and close brace, 'else' and 'while' (in do statement) tokens has indentation of the parent
                         case SyntaxKind.OpenBraceToken:
                         case SyntaxKind.CloseBraceToken:
-                        case SyntaxKind.OpenBracketToken:
-                        case SyntaxKind.CloseBracketToken:
                         case SyntaxKind.OpenParenToken:
                         case SyntaxKind.CloseParenToken:
                         case SyntaxKind.ElseKeyword:
@@ -506,6 +504,13 @@ namespace ts.formatting {
                             }
                             break;
                         }
+                        case SyntaxKind.OpenBracketToken:
+                        case SyntaxKind.CloseBracketToken: {
+                            if (container.kind !== SyntaxKind.MappedType) {
+                                return indentation;
+                            }
+                            break;
+                        }
                     }
                     // if token line equals to the line of containing node (this is a first token in the node) - use node indentation
                     return nodeStartLine !== line ? indentation + getEffectiveDelta(delta, container) : indentation;

src/services/formatting/rules.ts

@@ -87,6 +87,7 @@ namespace ts.formatting {
         public SpaceAfterLetConstInVariableDeclaration: Rule;
         public NoSpaceBeforeOpenParenInFuncCall: Rule;
         public SpaceAfterFunctionInFuncDecl: Rule;
+        public SpaceBeforeOpenParenInFuncDecl: Rule;
         public NoSpaceBeforeOpenParenInFuncDecl: Rule;
         public SpaceAfterVoidOperator: Rule;
 
@@ -112,6 +113,7 @@ namespace ts.formatting {
         // TypeScript-specific rules
 
         // Treat constructor as an identifier in a function declaration, and remove spaces between constructor and following left parentheses
+        public SpaceAfterConstructor: Rule;
         public NoSpaceAfterConstructor: Rule;
 
         // Use of module as a function call. e.g.: import m2 = module("m2");
@@ -329,6 +331,7 @@ namespace ts.formatting {
             this.SpaceAfterLetConstInVariableDeclaration = new Rule(RuleDescriptor.create4(Shared.TokenRange.FromTokens([SyntaxKind.LetKeyword, SyntaxKind.ConstKeyword]), Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext, Rules.IsStartOfVariableDeclarationList), RuleAction.Space));
             this.NoSpaceBeforeOpenParenInFuncCall = new Rule(RuleDescriptor.create2(Shared.TokenRange.Any, SyntaxKind.OpenParenToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext, Rules.IsFunctionCallOrNewContext, Rules.IsPreviousTokenNotComma), RuleAction.Delete));
             this.SpaceAfterFunctionInFuncDecl = new Rule(RuleDescriptor.create3(SyntaxKind.FunctionKeyword, Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsFunctionDeclContext), RuleAction.Space));
+            this.SpaceBeforeOpenParenInFuncDecl = new Rule(RuleDescriptor.create2(Shared.TokenRange.Any, SyntaxKind.OpenParenToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext, Rules.IsFunctionDeclContext), RuleAction.Space));
             this.NoSpaceBeforeOpenParenInFuncDecl = new Rule(RuleDescriptor.create2(Shared.TokenRange.Any, SyntaxKind.OpenParenToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext, Rules.IsFunctionDeclContext), RuleAction.Delete));
             this.SpaceAfterVoidOperator = new Rule(RuleDescriptor.create3(SyntaxKind.VoidKeyword, Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext, Rules.IsVoidOpContext), RuleAction.Space));
 
@@ -352,13 +355,14 @@ namespace ts.formatting {
             // TypeScript-specific higher priority rules
 
             // Treat constructor as an identifier in a function declaration, and remove spaces between constructor and following left parentheses
+            this.SpaceAfterConstructor = new Rule(RuleDescriptor.create1(SyntaxKind.ConstructorKeyword, SyntaxKind.OpenParenToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext), RuleAction.Space));
             this.NoSpaceAfterConstructor = new Rule(RuleDescriptor.create1(SyntaxKind.ConstructorKeyword, SyntaxKind.OpenParenToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext), RuleAction.Delete));
 
             // Use of module as a function call. e.g.: import m2 = module("m2");
             this.NoSpaceAfterModuleImport = new Rule(RuleDescriptor.create2(Shared.TokenRange.FromTokens([SyntaxKind.ModuleKeyword, SyntaxKind.RequireKeyword]), SyntaxKind.OpenParenToken), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext), RuleAction.Delete));
 
             // Add a space around certain TypeScript keywords
-            this.SpaceAfterCertainTypeScriptKeywords = new Rule(RuleDescriptor.create4(Shared.TokenRange.FromTokens([SyntaxKind.AbstractKeyword, SyntaxKind.ClassKeyword, SyntaxKind.DeclareKeyword, SyntaxKind.DefaultKeyword, SyntaxKind.EnumKeyword, SyntaxKind.ExportKeyword, SyntaxKind.ExtendsKeyword, SyntaxKind.GetKeyword, SyntaxKind.ImplementsKeyword, SyntaxKind.ImportKeyword, SyntaxKind.InterfaceKeyword, SyntaxKind.ModuleKeyword, SyntaxKind.NamespaceKeyword, SyntaxKind.PrivateKeyword, SyntaxKind.PublicKeyword, SyntaxKind.ProtectedKeyword, SyntaxKind.SetKeyword, SyntaxKind.StaticKeyword, SyntaxKind.TypeKeyword, SyntaxKind.FromKeyword]), Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext), RuleAction.Space));
+            this.SpaceAfterCertainTypeScriptKeywords = new Rule(RuleDescriptor.create4(Shared.TokenRange.FromTokens([SyntaxKind.AbstractKeyword, SyntaxKind.ClassKeyword, SyntaxKind.DeclareKeyword, SyntaxKind.DefaultKeyword, SyntaxKind.EnumKeyword, SyntaxKind.ExportKeyword, SyntaxKind.ExtendsKeyword, SyntaxKind.GetKeyword, SyntaxKind.ImplementsKeyword, SyntaxKind.ImportKeyword, SyntaxKind.InterfaceKeyword, SyntaxKind.ModuleKeyword, SyntaxKind.NamespaceKeyword, SyntaxKind.PrivateKeyword, SyntaxKind.PublicKeyword, SyntaxKind.ProtectedKeyword, SyntaxKind.ReadonlyKeyword, SyntaxKind.SetKeyword, SyntaxKind.StaticKeyword, SyntaxKind.TypeKeyword, SyntaxKind.FromKeyword, SyntaxKind.KeyOfKeyword]), Shared.TokenRange.Any), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext), RuleAction.Space));
             this.SpaceBeforeCertainTypeScriptKeywords = new Rule(RuleDescriptor.create4(Shared.TokenRange.Any, Shared.TokenRange.FromTokens([SyntaxKind.ExtendsKeyword, SyntaxKind.ImplementsKeyword, SyntaxKind.FromKeyword])), RuleOperation.create2(new RuleOperationContext(Rules.IsNonJsxSameLineTokenContext), RuleAction.Space));
 
             // Treat string literals in module names as identifiers, and add a space between the literal and the opening Brace braces, e.g.: module "m2" {
@@ -437,7 +441,7 @@ namespace ts.formatting {
                 this.NoSpaceBeforeEqualInJsxAttribute, this.NoSpaceAfterEqualInJsxAttribute,
 
                 // TypeScript-specific rules
-                this.NoSpaceAfterConstructor, this.NoSpaceAfterModuleImport,
+                this.NoSpaceAfterModuleImport,
                 this.SpaceAfterCertainTypeScriptKeywords, this.SpaceBeforeCertainTypeScriptKeywords,
                 this.SpaceAfterModuleName,
                 this.SpaceBeforeArrow, this.SpaceAfterArrow,
@@ -462,7 +466,6 @@ namespace ts.formatting {
                 this.NoSpaceBeforeOpenBracket,
                 this.NoSpaceAfterCloseBracket,
                 this.SpaceAfterSemicolon,
-                this.NoSpaceBeforeOpenParenInFuncDecl,
                 this.SpaceBetweenStatements, this.SpaceAfterTryFinally
             ];
 
@@ -575,6 +578,8 @@ namespace ts.formatting {
                     return context.currentTokenSpan.kind === SyntaxKind.EqualsToken || context.nextTokenSpan.kind === SyntaxKind.EqualsToken;
                 // "in" keyword in for (let x in []) { }
                 case SyntaxKind.ForInStatement:
+                // "in" keyword in [P in keyof T]: T[P]
+                case SyntaxKind.TypeParameter:
                     return context.currentTokenSpan.kind === SyntaxKind.InKeyword || context.nextTokenSpan.kind === SyntaxKind.InKeyword;
                 // Technically, "of" is not a binary operator, but format it the same way as "in"
                 case SyntaxKind.ForOfStatement:
@@ -836,6 +841,7 @@ namespace ts.formatting {
             switch (parent.kind) {
                 case SyntaxKind.TypeReference:
                 case SyntaxKind.TypeAssertionExpression:
+                case SyntaxKind.TypeAliasDeclaration:
                 case SyntaxKind.ClassDeclaration:
                 case SyntaxKind.ClassExpression:
                 case SyntaxKind.InterfaceDeclaration:

src/services/formatting/rulesProvider.ts

@@ -38,6 +38,13 @@ namespace ts.formatting {
         private createActiveRules(options: ts.FormatCodeSettings): Rule[] {
             let rules = this.globalRules.HighPriorityCommonRules.slice(0);
 
+            if (options.insertSpaceAfterConstructor) {
+                rules.push(this.globalRules.SpaceAfterConstructor);
+            }
+            else {
+                rules.push(this.globalRules.NoSpaceAfterConstructor);
+            }
+
             if (options.insertSpaceAfterCommaDelimiter) {
                 rules.push(this.globalRules.SpaceAfterComma);
             }
@@ -128,6 +135,13 @@ namespace ts.formatting {
                 rules.push(this.globalRules.NoSpaceAfterBinaryOperator);
             }
 
+            if (options.insertSpaceBeforeFunctionParenthesis) {
+                rules.push(this.globalRules.SpaceBeforeOpenParenInFuncDecl);
+            }
+            else {
+                rules.push(this.globalRules.NoSpaceBeforeOpenParenInFuncDecl);
+            }
+
             if (options.placeOpenBraceOnNewLineForControlBlocks) {
                 rules.push(this.globalRules.NewLineBeforeOpenBraceInControl);
             }

src/services/formatting/smartIndenter.ts

@@ -438,6 +438,7 @@ namespace ts.formatting {
                 case SyntaxKind.ModuleBlock:
                 case SyntaxKind.ObjectLiteralExpression:
                 case SyntaxKind.TypeLiteral:
+                case SyntaxKind.MappedType:
                 case SyntaxKind.TupleType:
                 case SyntaxKind.CaseBlock:
                 case SyntaxKind.DefaultClause:

src/services/types.ts

@@ -418,6 +418,7 @@ namespace ts {
         InsertSpaceAfterCommaDelimiter: boolean;
         InsertSpaceAfterSemicolonInForStatements: boolean;
         InsertSpaceBeforeAndAfterBinaryOperators: boolean;
+        InsertSpaceAfterConstructor?: boolean;
         InsertSpaceAfterKeywordsInControlFlowStatements: boolean;
         InsertSpaceAfterFunctionKeywordForAnonymousFunctions: boolean;
         InsertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis: boolean;
@@ -426,6 +427,7 @@ namespace ts {
         InsertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces: boolean;
         InsertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces?: boolean;
         InsertSpaceAfterTypeAssertion?: boolean;
+        InsertSpaceBeforeFunctionParenthesis?: boolean;
         PlaceOpenBraceOnNewLineForFunctions: boolean;
         PlaceOpenBraceOnNewLineForControlBlocks: boolean;
     }
@@ -434,6 +436,7 @@ namespace ts {
         insertSpaceAfterCommaDelimiter?: boolean;
         insertSpaceAfterSemicolonInForStatements?: boolean;
         insertSpaceBeforeAndAfterBinaryOperators?: boolean;
+        insertSpaceAfterConstructor?: boolean;
         insertSpaceAfterKeywordsInControlFlowStatements?: boolean;
         insertSpaceAfterFunctionKeywordForAnonymousFunctions?: boolean;
         insertSpaceAfterOpeningAndBeforeClosingNonemptyParenthesis?: boolean;
@@ -442,6 +445,7 @@ namespace ts {
         insertSpaceAfterOpeningAndBeforeClosingTemplateStringBraces?: boolean;
         insertSpaceAfterOpeningAndBeforeClosingJsxExpressionBraces?: boolean;
         insertSpaceAfterTypeAssertion?: boolean;
+        insertSpaceBeforeFunctionParenthesis?: boolean;
         placeOpenBraceOnNewLineForFunctions?: boolean;
         placeOpenBraceOnNewLineForControlBlocks?: boolean;
     }