Merge remote-tracking branch 'upstream/main' into es2022

package-lock.json

@@ -325,18 +325,18 @@
             }
         },
         "@octokit/openapi-types": {
-            "version": "11.1.0",
-            "resolved": "https://registry.npmjs.org/@octokit/openapi-types/-/openapi-types-11.1.0.tgz",
-            "integrity": "sha512-dWZfYvCCdjZzDYA3lIAMF72Q0jld8xidqCq5Ryw09eBJXZdcM6he0vWBTvw/b5UnGYqexxOyHWgfrsTlUJL3Gw==",
+            "version": "11.2.0",
+            "resolved": "https://registry.npmjs.org/@octokit/openapi-types/-/openapi-types-11.2.0.tgz",
+            "integrity": "sha512-PBsVO+15KSlGmiI8QAzaqvsNlZlrDlyAJYcrXBCvVUxCp7VnXjkwPoFHgjEJXx3WF9BAwkA6nfCUA7i9sODzKA==",
             "dev": true
         },
         "@octokit/plugin-paginate-rest": {
-            "version": "2.16.9",
-            "resolved": "https://registry.npmjs.org/@octokit/plugin-paginate-rest/-/plugin-paginate-rest-2.16.9.tgz",
-            "integrity": "sha512-gfSCMgz5scFKsR0dW4jaYsDJVt/UwCHp4dF7sHlmSekZvwzvLiOAGZ4MQkEsL5DW9hIk2W+UQkYZMTA1b6Wsqw==",
+            "version": "2.17.0",
+            "resolved": "https://registry.npmjs.org/@octokit/plugin-paginate-rest/-/plugin-paginate-rest-2.17.0.tgz",
+            "integrity": "sha512-tzMbrbnam2Mt4AhuyCHvpRkS0oZ5MvwwcQPYGtMv4tUa5kkzG58SVB0fcsLulOZQeRnOgdkZWkRUiyBlh0Bkyw==",
             "dev": true,
             "requires": {
-                "@octokit/types": "^6.33.0"
+                "@octokit/types": "^6.34.0"
             }
         },
         "@octokit/plugin-request-log": {
@@ -346,12 +346,12 @@
             "dev": true
         },
         "@octokit/plugin-rest-endpoint-methods": {
-            "version": "5.12.1",
-            "resolved": "https://registry.npmjs.org/@octokit/plugin-rest-endpoint-methods/-/plugin-rest-endpoint-methods-5.12.1.tgz",
-            "integrity": "sha512-0nY3htfl6x9UkPcqv8pm9vOC/bTA7f4IMDWln13neHRdNWQvOQgZ9fRxK7BAc74rye4yVINEFi9Yb9rnGUvosA==",
+            "version": "5.13.0",
+            "resolved": "https://registry.npmjs.org/@octokit/plugin-rest-endpoint-methods/-/plugin-rest-endpoint-methods-5.13.0.tgz",
+            "integrity": "sha512-uJjMTkN1KaOIgNtUPMtIXDOjx6dGYysdIFhgA52x4xSadQCz3b/zJexvITDVpANnfKPW/+E0xkOvLntqMYpviA==",
             "dev": true,
             "requires": {
-                "@octokit/types": "^6.33.0",
+                "@octokit/types": "^6.34.0",
                 "deprecation": "^2.3.1"
             }
         },
@@ -393,12 +393,12 @@
             }
         },
         "@octokit/types": {
-            "version": "6.33.0",
-            "resolved": "https://registry.npmjs.org/@octokit/types/-/types-6.33.0.tgz",
-            "integrity": "sha512-0zffZ048M0UhthyPXQHLz4038Ak46nMWZXkzlXvXB/M/L1jYPBceq4iZj4qjKVrvveaJrrgKdJ9+3yUuITfcCw==",
+            "version": "6.34.0",
+            "resolved": "https://registry.npmjs.org/@octokit/types/-/types-6.34.0.tgz",
+            "integrity": "sha512-s1zLBjWhdEI2zwaoSgyOFoKSl109CUcVBCc7biPJ3aAf6LGLU6szDvi31JPU7bxfla2lqfhjbbg/5DdFNxOwHw==",
             "dev": true,
             "requires": {
-                "@octokit/openapi-types": "^11.1.0"
+                "@octokit/openapi-types": "^11.2.0"
             }
         },
         "@types/browserify": {
@@ -430,9 +430,9 @@
             "dev": true
         },
         "@types/glob": {
-            "version": "7.1.4",
-            "resolved": "https://registry.npmjs.org/@types/glob/-/glob-7.1.4.tgz",
-            "integrity": "sha512-w+LsMxKyYQm347Otw+IfBXOv9UWVjpHpCDdbBMt8Kz/xbvCYNjP+0qPh91Km3iKfSRLBB0P7fAMf0KHrPu+MyA==",
+            "version": "7.2.0",
+            "resolved": "https://registry.npmjs.org/@types/glob/-/glob-7.2.0.tgz",
+            "integrity": "sha512-ZUxbzKl0IfJILTS6t7ip5fQQM/J3TJYubDm3nMbgubNNYS62eXeUpoLUC8/7fJNiFYHTrGPQn7hspDUzIHX3UA==",
             "dev": true,
             "requires": {
                 "@types/minimatch": "*",
@@ -676,9 +676,9 @@
             "dev": true
         },
         "@types/node": {
-            "version": "16.10.3",
-            "resolved": "https://registry.npmjs.org/@types/node/-/node-16.10.3.tgz",
-            "integrity": "sha512-ho3Ruq+fFnBrZhUYI46n/bV2GjwzSkwuT4dTf0GkuNFmnb8nq4ny2z9JEVemFi6bdEJanHLlYfy9c6FN9B9McQ==",
+            "version": "16.11.6",
+            "resolved": "https://registry.npmjs.org/@types/node/-/node-16.11.6.tgz",
+            "integrity": "sha512-ua7PgUoeQFjmWPcoo9khiPum3Pd60k4/2ZGXt18sm2Slk0W0xZTqt5Y0Ny1NyBiN1EVQ/+FaF9NcY4Qe6rwk5w==",
             "dev": true
         },
         "@types/node-fetch": {
@@ -1658,9 +1658,9 @@
                     }
                 },
                 "is-core-module": {
-                    "version": "2.7.0",
-                    "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.7.0.tgz",
-                    "integrity": "sha512-ByY+tjCciCr+9nLryBYcSD50EOGWt95c7tIsKTG1J2ixKKXPvF7Ej3AVd+UfDydAJom3biBGDBALaO79ktwgEQ==",
+                    "version": "2.8.0",
+                    "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.8.0.tgz",
+                    "integrity": "sha512-vd15qHsaqrRL7dtH6QNuy0ndJmRDrS9HAM1CAiSifNUFv4x1a0CCVsj18hJ1mShxIG6T2i1sO78MkP56r0nYRw==",
                     "dev": true,
                     "requires": {
                         "has": "^1.0.3"
@@ -5339,9 +5339,9 @@
             "dev": true
         },
         "mocha": {
-            "version": "9.1.2",
-            "resolved": "https://registry.npmjs.org/mocha/-/mocha-9.1.2.tgz",
-            "integrity": "sha512-ta3LtJ+63RIBP03VBjMGtSqbe6cWXRejF9SyM9Zyli1CKZJZ+vfCTj3oW24V7wAphMJdpOFLoMI3hjJ1LWbs0w==",
+            "version": "9.1.3",
+            "resolved": "https://registry.npmjs.org/mocha/-/mocha-9.1.3.tgz",
+            "integrity": "sha512-Xcpl9FqXOAYqI3j79pEtHBBnQgVXIhpULjGQa7DVb0Po+VzmSIK9kanAiWLHoRR/dbZ2qpdPshuXr8l1VaHCzw==",
             "dev": true,
             "requires": {
                 "@ungap/promise-all-settled": "1.1.2",
@@ -5730,9 +5730,9 @@
                     }
                 },
                 "is-core-module": {
-                    "version": "2.7.0",
-                    "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.7.0.tgz",
-                    "integrity": "sha512-ByY+tjCciCr+9nLryBYcSD50EOGWt95c7tIsKTG1J2ixKKXPvF7Ej3AVd+UfDydAJom3biBGDBALaO79ktwgEQ==",
+                    "version": "2.8.0",
+                    "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.8.0.tgz",
+                    "integrity": "sha512-vd15qHsaqrRL7dtH6QNuy0ndJmRDrS9HAM1CAiSifNUFv4x1a0CCVsj18hJ1mShxIG6T2i1sO78MkP56r0nYRw==",
                     "dev": true,
                     "requires": {
                         "has": "^1.0.3"
@@ -6797,9 +6797,9 @@
             }
         },
         "shell-quote": {
-            "version": "1.7.2",
-            "resolved": "https://registry.npmjs.org/shell-quote/-/shell-quote-1.7.2.tgz",
-            "integrity": "sha512-mRz/m/JVscCrkMyPqHc/bczi3OQHkLTqXHEFu0zDhK/qfv3UcOA4SVmRCLmos4bhjr9ekVQubj/R7waKapmiQg==",
+            "version": "1.7.3",
+            "resolved": "https://registry.npmjs.org/shell-quote/-/shell-quote-1.7.3.tgz",
+            "integrity": "sha512-Vpfqwm4EnqGdlsBFNmHhxhElJYrdfcxPThu+ryKS5J8L/fhAwLazFZtq+S+TWZ9ANj2piSQLGj6NQg+lKPmxrw==",
             "dev": true
         },
         "side-channel": {

scripts/build/findUpDir.js

@@ -0,0 +1,21 @@
+const { join, resolve, dirname } = require("path");
+const { existsSync } = require("fs");
+
+// search directories upward to avoid hard-wired paths based on the
+// build tree (same as src/harness/findUpDir.ts)
+
+function findUpFile(name) {
+    let dir = __dirname;
+    while (true) {
+        const fullPath = join(dir, name);
+        if (existsSync(fullPath)) return fullPath;
+        const up = resolve(dir, "..");
+        if (up === dir) return name; // it'll fail anyway
+        dir = up;
+    }
+}
+exports.findUpFile = findUpFile;
+
+const findUpRoot = () =>
+    findUpRoot.cached || (findUpRoot.cached = dirname(findUpFile("Gulpfile.js")));
+exports.findUpRoot = findUpRoot;

scripts/build/projects.js

@@ -1,5 +1,7 @@
 // @ts-check
 const { exec, Debouncer } = require("./utils");
+const { resolve } = require("path");
+const { findUpRoot } = require("./findUpDir");
 
 class ProjectQueue {
     /**
@@ -33,7 +35,13 @@ class ProjectQueue {
     }
 }
 
-const projectBuilder = new ProjectQueue((projects, lkg, force) => exec(process.execPath, [lkg ? "./lib/tsc" : "./built/local/tsc", "-b", ...(force ? ["--force"] : []), ...projects], { hidePrompt: true }));
+const execTsc = (lkg, ...args) =>
+    exec(process.execPath,
+         [resolve(findUpRoot(), lkg ? "./lib/tsc" : "./built/local/tsc"),
+          "-b", ...args],
+         { hidePrompt: true })
+
+const projectBuilder = new ProjectQueue((projects, lkg, force) => execTsc(lkg, ...(force ? ["--force"] : []), ...projects));
 
 /**
  * @param {string} project
@@ -43,14 +51,14 @@ const projectBuilder = new ProjectQueue((projects, lkg, force) => exec(process.e
  */
 exports.buildProject = (project, { lkg, force } = {}) => projectBuilder.enqueue(project, { lkg, force });
 
-const projectCleaner = new ProjectQueue((projects, lkg) => exec(process.execPath, [lkg ? "./lib/tsc" : "./built/local/tsc", "-b", "--clean", ...projects], { hidePrompt: true }));
+const projectCleaner = new ProjectQueue((projects, lkg) => execTsc(lkg, "--clean", ...projects));
 
 /**
  * @param {string} project
  */
 exports.cleanProject = (project) => projectCleaner.enqueue(project);
 
-const projectWatcher = new ProjectQueue((projects) => exec(process.execPath, ["./lib/tsc", "-b", "--watch", ...projects], { hidePrompt: true }));
+const projectWatcher = new ProjectQueue((projects) => execTsc(true, "--watch", ...projects));
 
 /**
  * @param {string} project

scripts/build/tests.js

@@ -9,6 +9,7 @@ const log = require("fancy-log");
 const cmdLineOptions = require("./options");
 const { CancellationToken } = require("prex");
 const { exec } = require("./utils");
+const { findUpFile } = require("./findUpDir");
 
 const mochaJs = require.resolve("mocha/bin/_mocha");
 exports.localBaseline = "tests/baselines/local/";
@@ -73,11 +74,11 @@ async function runConsoleTests(runJs, defaultReporter, runInParallel, watchMode,
     /** @type {string[]} */
     let args = [];
 
-    // timeout normally isn"t necessary but Travis-CI has been timing out on compiler baselines occasionally
+    // timeout normally isn't necessary but Travis-CI has been timing out on compiler baselines occasionally
     // default timeout is 2sec which really should be enough, but maybe we just need a small amount longer
     if (!runInParallel) {
         args.push(mochaJs);
-        args.push("-R", "scripts/failed-tests");
+        args.push("-R", findUpFile("scripts/failed-tests.js"));
         args.push("-O", '"reporter=' + reporter + (keepFailed ? ",keepFailed=true" : "") + '"');
         if (tests) {
             args.push("-g", `"${tests}"`);

scripts/build/utils.js

@@ -9,12 +9,11 @@ const del = require("del");
 const File = require("vinyl");
 const ts = require("../../lib/typescript");
 const chalk = require("chalk");
+const which = require("which");
 const { spawn } = require("child_process");
 const { CancellationToken, CancelError, Deferred } = require("prex");
 const { Readable, Duplex } = require("stream");
 
-const isWindows = /^win/.test(process.platform);
-
 /**
  * Executes the provided command once with the supplied arguments.
  * @param {string} cmd
@@ -32,12 +31,8 @@ function exec(cmd, args, options = {}) {
         const { ignoreExitCode, cancelToken = CancellationToken.none, waitForExit = true } = options;
         cancelToken.throwIfCancellationRequested();
 
-        // TODO (weswig): Update child_process types to add windowsVerbatimArguments to the type definition
-        const subshellFlag = isWindows ? "/c" : "-c";
-        const command = isWindows ? [possiblyQuote(cmd), ...args] : [`${cmd} ${args.join(" ")}`];
-
         if (!options.hidePrompt) log(`> ${chalk.green(cmd)} ${args.join(" ")}`);
-        const proc = spawn(isWindows ? "cmd" : "/bin/sh", [subshellFlag, ...command], { stdio: waitForExit ? "inherit" : "ignore", windowsVerbatimArguments: true });
+        const proc = spawn(which.sync(cmd), args, { stdio: waitForExit ? "inherit" : "ignore" });
         const registration = cancelToken.register(() => {
             log(`${chalk.red("killing")} '${chalk.green(cmd)} ${args.join(" ")}'...`);
             proc.kill("SIGINT");
@@ -68,13 +63,6 @@ function exec(cmd, args, options = {}) {
 }
 exports.exec = exec;
 
-/**
- * @param {string} cmd
- */
-function possiblyQuote(cmd) {
-    return cmd.indexOf(" ") >= 0 ? `"${cmd}"` : cmd;
-}
-
 /**
  * @param {ts.Diagnostic[]} diagnostics
  * @param {{ cwd?: string, pretty?: boolean }} [options]
@@ -440,4 +428,4 @@ class Debouncer {
         }
     }
 }
-exports.Debouncer = Debouncer;
+exports.Debouncer = Debouncer;

src/compiler/binder.ts

@@ -2947,6 +2947,7 @@ namespace ts {
                 case SyntaxKind.MethodDeclaration:
                 case SyntaxKind.GetAccessor:
                 case SyntaxKind.SetAccessor:
+                case SyntaxKind.ClassStaticBlockDeclaration:
                     // this.foo assignment in a JavaScript class
                     // Bind this property to the containing class
                     const containingClass = thisContainer.parent;

src/compiler/checker.ts

@@ -3275,21 +3275,40 @@ namespace ts {
                         const namespaceName = getFullyQualifiedName(namespace);
                         const declarationName = declarationNameToString(right);
                         const suggestionForNonexistentModule = getSuggestedSymbolForNonexistentModule(right, namespace);
-                        const exportedTypeSymbol = getMergedSymbol(getSymbol(getExportsOfSymbol(namespace), right.escapedText, SymbolFlags.Type));
-                        const containingQualifiedName = isQualifiedName(name) && getContainingQualifiedNameNode(name);
-                        const canSuggestTypeof = containingQualifiedName && !isTypeOfExpression(containingQualifiedName.parent) && tryGetQualifiedNameAsValue(containingQualifiedName);
                         if (suggestionForNonexistentModule) {
                             error(right, Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, namespaceName, declarationName, symbolToString(suggestionForNonexistentModule));
+                            return undefined;
                         }
-                        else if (canSuggestTypeof) {
-                            error(containingQualifiedName, Diagnostics._0_refers_to_a_value_but_is_being_used_as_a_type_here_Did_you_mean_typeof_0, entityNameToString(containingQualifiedName));
+
+                        const containingQualifiedName = isQualifiedName(name) && getContainingQualifiedNameNode(name);
+                        const canSuggestTypeof = globalObjectType // <-- can't pull on types if global types aren't initialized yet
+                            && (meaning & SymbolFlags.Type)
+                            && containingQualifiedName
+                            && !isTypeOfExpression(containingQualifiedName.parent)
+                            && tryGetQualifiedNameAsValue(containingQualifiedName);
+                        if (canSuggestTypeof) {
+                            error(
+                                containingQualifiedName,
+                                Diagnostics._0_refers_to_a_value_but_is_being_used_as_a_type_here_Did_you_mean_typeof_0,
+                                entityNameToString(containingQualifiedName)
+                            );
+                            return undefined;
                         }
-                        else if (meaning & SymbolFlags.Namespace && exportedTypeSymbol && isQualifiedName(name.parent)) {
-                            error(name.parent.right, Diagnostics.Cannot_access_0_1_because_0_is_a_type_but_not_a_namespace_Did_you_mean_to_retrieve_the_type_of_the_property_1_in_0_with_0_1, symbolToString(exportedTypeSymbol), unescapeLeadingUnderscores(name.parent.right.escapedText));
-                        }
-                        else {
-                            error(right, Diagnostics.Namespace_0_has_no_exported_member_1, namespaceName, declarationName);
+
+                        if (meaning & SymbolFlags.Namespace && isQualifiedName(name.parent)) {
+                            const exportedTypeSymbol = getMergedSymbol(getSymbol(getExportsOfSymbol(namespace), right.escapedText, SymbolFlags.Type));
+                            if (exportedTypeSymbol) {
+                                error(
+                                    name.parent.right,
+                                    Diagnostics.Cannot_access_0_1_because_0_is_a_type_but_not_a_namespace_Did_you_mean_to_retrieve_the_type_of_the_property_1_in_0_with_0_1,
+                                    symbolToString(exportedTypeSymbol),
+                                    unescapeLeadingUnderscores(name.parent.right.escapedText)
+                                );
+                                return undefined;
+                            }
                         }
+
+                        error(right, Diagnostics.Namespace_0_has_no_exported_member_1, namespaceName, declarationName);
                     }
                     return undefined;
                 }
@@ -3416,7 +3435,8 @@ namespace ts {
                     findAncestor(location, isExportDeclaration)?.moduleSpecifier ||
                     (isModuleDeclaration(location) ? location : location.parent && isModuleDeclaration(location.parent) && location.parent.name === location ? location.parent : undefined)?.name ||
                     (isLiteralImportTypeNode(location) ? location : undefined)?.argument.literal;
-            const resolvedModule = getResolvedModule(currentSourceFile, moduleReference, contextSpecifier && isStringLiteralLike(contextSpecifier) ? getModeForUsageLocation(currentSourceFile, contextSpecifier) : undefined)!; // TODO: GH#18217
+            const mode = contextSpecifier && isStringLiteralLike(contextSpecifier) ? getModeForUsageLocation(currentSourceFile, contextSpecifier) : currentSourceFile.impliedNodeFormat;
+            const resolvedModule = getResolvedModule(currentSourceFile, moduleReference, mode)!; // TODO: GH#18217
             const resolutionDiagnostic = resolvedModule && getResolutionDiagnostic(compilerOptions, resolvedModule);
             const sourceFile = resolvedModule && !resolutionDiagnostic && host.getSourceFile(resolvedModule.resolvedFileName);
             if (sourceFile) {
@@ -3655,8 +3675,8 @@ namespace ts {
             if (exportEquals !== moduleSymbol) {
                 const type = getTypeOfSymbol(exportEquals);
                 if (shouldTreatPropertiesOfExternalModuleAsExports(type)) {
-                    getPropertiesOfType(type).forEach(symbol => {
-                        cb(symbol, symbol.escapedName);
+                    forEachPropertyOfType(type, (symbol, escapedName) => {
+                        cb(symbol, escapedName);
                     });
                 }
             }
@@ -4032,13 +4052,17 @@ namespace ts {
         function getNamedMembers(members: SymbolTable): Symbol[] {
             let result: Symbol[] | undefined;
             members.forEach((symbol, id) => {
-                if (!isReservedMemberName(id) && symbolIsValue(symbol)) {
+                if (isNamedMember(symbol, id)) {
                     (result || (result = [])).push(symbol);
                 }
             });
             return result || emptyArray;
         }
 
+        function isNamedMember(member: Symbol, escapedName: __String) {
+            return !isReservedMemberName(escapedName) && symbolIsValue(member);
+        }
+
         function getNamedOrIndexSignatureMembers(members: SymbolTable): Symbol[] {
             const result = getNamedMembers(members);
             const index = getIndexSymbolFromSymbolTable(members);
@@ -4972,7 +4996,7 @@ namespace ts {
                     const typeParameterNode = typeParameterToDeclarationWithConstraint(getTypeParameterFromMappedType(type), context, appropriateConstraintTypeNode);
                     const nameTypeNode = type.declaration.nameType ? typeToTypeNodeHelper(getNameTypeFromMappedType(type)!, context) : undefined;
                     const templateTypeNode = typeToTypeNodeHelper(removeMissingType(getTemplateTypeFromMappedType(type), !!(getMappedTypeModifiers(type) & MappedTypeModifiers.IncludeOptional)), context);
-                    const mappedTypeNode = factory.createMappedTypeNode(readonlyToken, typeParameterNode, nameTypeNode, questionToken, templateTypeNode);
+                    const mappedTypeNode = factory.createMappedTypeNode(readonlyToken, typeParameterNode, nameTypeNode, questionToken, templateTypeNode, /*members*/ undefined);
                     context.approximateLength += 10;
                     return setEmitFlags(mappedTypeNode, EmitFlags.SingleLine);
                 }
@@ -11570,6 +11594,17 @@ namespace ts {
                 getPropertiesOfObjectType(type);
         }
 
+        function forEachPropertyOfType(type: Type, action: (symbol: Symbol, escapedName: __String) => void): void {
+            type = getReducedApparentType(type);
+            if (type.flags & TypeFlags.StructuredType) {
+                resolveStructuredTypeMembers(type as StructuredType).members.forEach((symbol, escapedName) => {
+                    if (isNamedMember(symbol, escapedName)) {
+                        action(symbol, escapedName);
+                    }
+                });
+            }
+        }
+
         function isTypeInvalidDueToUnionDiscriminant(contextualType: Type, obj: ObjectLiteralExpression | JsxAttributes): boolean {
             const list = obj.properties as NodeArray<ObjectLiteralElementLike | JsxAttributeLike>;
             return list.some(property => {
@@ -12580,7 +12615,7 @@ namespace ts {
                 if (!node) return false;
                 switch (node.kind) {
                     case SyntaxKind.Identifier:
-                        return (node as Identifier).escapedText === argumentsSymbol.escapedName && getResolvedSymbol(node as Identifier) === argumentsSymbol;
+                        return (node as Identifier).escapedText === argumentsSymbol.escapedName && getReferencedValueSymbol(node as Identifier) === argumentsSymbol;
 
                     case SyntaxKind.PropertyDeclaration:
                     case SyntaxKind.MethodDeclaration:
@@ -14168,13 +14203,13 @@ namespace ts {
         }
 
         function removeStringLiteralsMatchedByTemplateLiterals(types: Type[]) {
-            const templates = filter(types, isPatternLiteralType);
+            const templates = filter(types, isPatternLiteralType) as TemplateLiteralType[];
             if (templates.length) {
                 let i = types.length;
                 while (i > 0) {
                     i--;
                     const t = types[i];
-                    if (t.flags & TypeFlags.StringLiteral && some(templates, template => isTypeSubtypeOf(t, template))) {
+                    if (t.flags & TypeFlags.StringLiteral && some(templates, template => isTypeMatchedByTemplateLiteralType(t, template))) {
                         orderedRemoveItemAt(types, i);
                     }
                 }
@@ -15314,13 +15349,6 @@ namespace ts {
             return type[cache] = type;
         }
 
-        function isConditionalTypeAlwaysTrueDisregardingInferTypes(type: ConditionalType) {
-            const extendsInferParamMapper = type.root.inferTypeParameters && createTypeMapper(type.root.inferTypeParameters, map(type.root.inferTypeParameters, () => wildcardType));
-            const checkType = type.checkType;
-            const extendsType = type.extendsType;
-            return isTypeAssignableTo(getRestrictiveInstantiation(checkType), getRestrictiveInstantiation(instantiateType(extendsType, extendsInferParamMapper)));
-        }
-
         function getSimplifiedConditionalType(type: ConditionalType, writing: boolean) {
             const checkType = type.checkType;
             const extendsType = type.extendsType;
@@ -15644,6 +15672,12 @@ namespace ts {
             return result;
         }
 
+        function isDistributionDependent(root: ConditionalRoot) {
+            return root.isDistributive && (
+                isTypeParameterPossiblyReferenced(root.checkType as TypeParameter, root.node.trueType) ||
+                isTypeParameterPossiblyReferenced(root.checkType as TypeParameter, root.node.falseType));
+        }
+
         function getTypeFromConditionalTypeNode(node: ConditionalTypeNode): Type {
             const links = getNodeLinks(node);
             if (!links.resolvedType) {
@@ -18192,13 +18226,12 @@ namespace ts {
                 let result = Ternary.False;
                 const saveErrorInfo = captureErrorCalculationState();
 
-                // Note that these checks are specifically ordered to produce correct results. In particular,
-                // we need to deconstruct unions before intersections (because unions are always at the top),
-                // and we need to handle "each" relations before "some" relations for the same kind of type.
-                if (source.flags & TypeFlags.UnionOrIntersection || target.flags & TypeFlags.UnionOrIntersection) {
-                    result = getConstituentCount(source) * getConstituentCount(target) >= 4 ?
-                        recursiveTypeRelatedTo(source, target, reportErrors, intersectionState | IntersectionState.UnionIntersectionCheck, recursionFlags) :
-                        structuredTypeRelatedTo(source, target, reportErrors, intersectionState | IntersectionState.UnionIntersectionCheck);
+                if ((source.flags & TypeFlags.Union || target.flags & TypeFlags.Union) && getConstituentCount(source) * getConstituentCount(target) < 4) {
+                    // We skip caching when source or target is a union with no more than three constituents.
+                    result = structuredTypeRelatedTo(source, target, reportErrors, intersectionState | IntersectionState.UnionIntersectionCheck);
+                }
+                else if (source.flags & TypeFlags.UnionOrIntersection || target.flags & TypeFlags.UnionOrIntersection) {
+                    result = recursiveTypeRelatedTo(source, target, reportErrors, intersectionState | IntersectionState.UnionIntersectionCheck, recursionFlags);
                 }
                 if (!result && !(source.flags & TypeFlags.Union) && (source.flags & (TypeFlags.StructuredOrInstantiable) || target.flags & TypeFlags.StructuredOrInstantiable)) {
                     if (result = recursiveTypeRelatedTo(source, target, reportErrors, intersectionState, recursionFlags)) {
@@ -18662,17 +18695,17 @@ namespace ts {
                 const maybeStart = maybeCount;
                 maybeKeys[maybeCount] = id;
                 maybeCount++;
+                const saveExpandingFlags = expandingFlags;
                 if (recursionFlags & RecursionFlags.Source) {
                     sourceStack[sourceDepth] = source;
                     sourceDepth++;
+                    if (!(expandingFlags & ExpandingFlags.Source) && isDeeplyNestedType(source, sourceStack, sourceDepth)) expandingFlags |= ExpandingFlags.Source;
                 }
                 if (recursionFlags & RecursionFlags.Target) {
                     targetStack[targetDepth] = target;
                     targetDepth++;
+                    if (!(expandingFlags & ExpandingFlags.Target) && isDeeplyNestedType(target, targetStack, targetDepth)) expandingFlags |= ExpandingFlags.Target;
                 }
-                const saveExpandingFlags = expandingFlags;
-                if (!(expandingFlags & ExpandingFlags.Source) && isDeeplyNestedType(source, sourceStack, sourceDepth)) expandingFlags |= ExpandingFlags.Source;
-                if (!(expandingFlags & ExpandingFlags.Target) && isDeeplyNestedType(target, targetStack, targetDepth)) expandingFlags |= ExpandingFlags.Target;
                 let originalHandler: typeof outofbandVarianceMarkerHandler;
                 let propagatingVarianceFlags: RelationComparisonResult = 0;
                 if (outofbandVarianceMarkerHandler) {
@@ -18698,13 +18731,13 @@ namespace ts {
                 if (outofbandVarianceMarkerHandler) {
                     outofbandVarianceMarkerHandler = originalHandler;
                 }
-                expandingFlags = saveExpandingFlags;
                 if (recursionFlags & RecursionFlags.Source) {
                     sourceDepth--;
                 }
                 if (recursionFlags & RecursionFlags.Target) {
                     targetDepth--;
                 }
+                expandingFlags = saveExpandingFlags;
                 if (result) {
                     if (result === Ternary.True || (sourceDepth === 0 && targetDepth === 0)) {
                         if (result === Ternary.True || result === Ternary.Maybe) {
@@ -19023,34 +19056,28 @@ namespace ts {
                     }
                 }
                 else if (target.flags & TypeFlags.Conditional) {
-                    const c = target as ConditionalType;
-                    // Check if the conditional is always true or always false but still deferred for distribution purposes
-                    const skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
-                    const skipFalse = !skipTrue && isConditionalTypeAlwaysTrueDisregardingInferTypes(c);
-
-                    // Instantiate with a replacement mapper if the conditional is distributive, replacing the check type with a clone of itself,
-                    // this way {x: string | number, y: string | number} -> (T extends T ? { x: T, y: T } : never) appropriately _fails_ when
-                    // T = string | number (since that will end up distributing and producing `{x: string, y: string} | {x: number, y: number}`,
-                    // to which `{x: string | number, y: string | number}` isn't assignable)
-                    let distributionMapper: TypeMapper | undefined;
-                    const checkVar = getActualTypeVariable(c.root.checkType);
-                    if (c.root.isDistributive && checkVar.flags & TypeFlags.TypeParameter) {
-                        const newParam = cloneTypeParameter(checkVar);
-                        distributionMapper = prependTypeMapping(checkVar, newParam, c.mapper);
-                        newParam.mapper = distributionMapper;
-                    }
-
-                    // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                    const expanding = isDeeplyNestedType(target, targetStack, targetDepth);
-                    let localResult: Ternary | undefined = expanding ? Ternary.Maybe : undefined;
-                    if (skipTrue || expanding || (localResult = isRelatedTo(source, distributionMapper ? instantiateType(getTypeFromTypeNode(c.root.node.trueType), distributionMapper) : getTrueTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false))) {
-                        if (!skipFalse && !expanding) {
-                            localResult = (localResult || Ternary.Maybe) & isRelatedTo(source, distributionMapper ? instantiateType(getTypeFromTypeNode(c.root.node.falseType), distributionMapper) : getFalseTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false);
-                        }
-                    }
-                    if (localResult) {
+                    // If we reach 10 levels of nesting for the same conditional type, assume it is an infinitely expanding recursive
+                    // conditional type and bail out with a Ternary.Maybe result.
+                    if (isDeeplyNestedType(target, targetStack, targetDepth, 10)) {
                         resetErrorInfo(saveErrorInfo);
-                        return localResult;
+                        return Ternary.Maybe;
+                    }
+                    const c = target as ConditionalType;
+                    // We check for a relationship to a conditional type target only when the conditional type has no
+                    // 'infer' positions and is not distributive or is distributive but doesn't reference the check type
+                    // parameter in either of the result types.
+                    if (!c.root.inferTypeParameters && !isDistributionDependent(c.root)) {
+                        // Check if the conditional is always true or always false but still deferred for distribution purposes.
+                        const skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
+                        const skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
+                        // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
+                        if (result = skipTrue ? Ternary.True : isRelatedTo(source, getTrueTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false)) {
+                            result &= skipFalse ? Ternary.True : isRelatedTo(source, getFalseTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false);
+                            if (result) {
+                                resetErrorInfo(saveErrorInfo);
+                                return result;
+                            }
+                        }
                     }
                 }
                 else if (target.flags & TypeFlags.TemplateLiteral) {
@@ -19062,8 +19089,7 @@ namespace ts {
                         // For example, `foo-${number}` is related to `foo-${string}` even though number isn't related to string.
                         instantiateType(source, makeFunctionTypeMapper(reportUnreliableMarkers));
                     }
-                    const result = inferTypesFromTemplateLiteralType(source, target as TemplateLiteralType);
-                    if (result && every(result, (r, i) => isValidTypeForTemplateLiteralPlaceholder(r, (target as TemplateLiteralType).types[i]))) {
+                    if (isTypeMatchedByTemplateLiteralType(source, target as TemplateLiteralType)) {
                         return Ternary.True;
                     }
                 }
@@ -19122,33 +19148,34 @@ namespace ts {
                     }
                 }
                 else if (source.flags & TypeFlags.Conditional) {
+                    // If we reach 10 levels of nesting for the same conditional type, assume it is an infinitely expanding recursive
+                    // conditional type and bail out with a Ternary.Maybe result.
+                    if (isDeeplyNestedType(source, sourceStack, sourceDepth, 10)) {
+                        resetErrorInfo(saveErrorInfo);
+                        return Ternary.Maybe;
+                    }
                     if (target.flags & TypeFlags.Conditional) {
-                        // If one of the conditionals under comparison seems to be infinitely expanding, stop comparing it - back out, try
-                        // the constraint, and failing that, give up trying to relate the two. This is the only way we can handle recursive conditional
-                        // types, which might expand forever.
-                        if (!isDeeplyNestedType(source, sourceStack, sourceDepth) && !isDeeplyNestedType(target, targetStack, targetDepth)) {
-                            // Two conditional types 'T1 extends U1 ? X1 : Y1' and 'T2 extends U2 ? X2 : Y2' are related if
-                            // one of T1 and T2 is related to the other, U1 and U2 are identical types, X1 is related to X2,
-                            // and Y1 is related to Y2.
-                            const sourceParams = (source as ConditionalType).root.inferTypeParameters;
-                            let sourceExtends = (source as ConditionalType).extendsType;
-                            let mapper: TypeMapper | undefined;
-                            if (sourceParams) {
-                                // If the source has infer type parameters, we instantiate them in the context of the target
-                                const ctx = createInferenceContext(sourceParams, /*signature*/ undefined, InferenceFlags.None, isRelatedToWorker);
-                                inferTypes(ctx.inferences, (target as ConditionalType).extendsType, sourceExtends, InferencePriority.NoConstraints | InferencePriority.AlwaysStrict);
-                                sourceExtends = instantiateType(sourceExtends, ctx.mapper);
-                                mapper = ctx.mapper;
+                        // Two conditional types 'T1 extends U1 ? X1 : Y1' and 'T2 extends U2 ? X2 : Y2' are related if
+                        // one of T1 and T2 is related to the other, U1 and U2 are identical types, X1 is related to X2,
+                        // and Y1 is related to Y2.
+                        const sourceParams = (source as ConditionalType).root.inferTypeParameters;
+                        let sourceExtends = (source as ConditionalType).extendsType;
+                        let mapper: TypeMapper | undefined;
+                        if (sourceParams) {
+                            // If the source has infer type parameters, we instantiate them in the context of the target
+                            const ctx = createInferenceContext(sourceParams, /*signature*/ undefined, InferenceFlags.None, isRelatedToWorker);
+                            inferTypes(ctx.inferences, (target as ConditionalType).extendsType, sourceExtends, InferencePriority.NoConstraints | InferencePriority.AlwaysStrict);
+                            sourceExtends = instantiateType(sourceExtends, ctx.mapper);
+                            mapper = ctx.mapper;
+                        }
+                        if (isTypeIdenticalTo(sourceExtends, (target as ConditionalType).extendsType) &&
+                            (isRelatedTo((source as ConditionalType).checkType, (target as ConditionalType).checkType, RecursionFlags.Both) || isRelatedTo((target as ConditionalType).checkType, (source as ConditionalType).checkType, RecursionFlags.Both))) {
+                            if (result = isRelatedTo(instantiateType(getTrueTypeFromConditionalType(source as ConditionalType), mapper), getTrueTypeFromConditionalType(target as ConditionalType), RecursionFlags.Both, reportErrors)) {
+                                result &= isRelatedTo(getFalseTypeFromConditionalType(source as ConditionalType), getFalseTypeFromConditionalType(target as ConditionalType), RecursionFlags.Both, reportErrors);
                             }
-                            if (isTypeIdenticalTo(sourceExtends, (target as ConditionalType).extendsType) &&
-                                (isRelatedTo((source as ConditionalType).checkType, (target as ConditionalType).checkType, RecursionFlags.Both) || isRelatedTo((target as ConditionalType).checkType, (source as ConditionalType).checkType, RecursionFlags.Both))) {
-                                if (result = isRelatedTo(instantiateType(getTrueTypeFromConditionalType(source as ConditionalType), mapper), getTrueTypeFromConditionalType(target as ConditionalType), RecursionFlags.Both, reportErrors)) {
-                                    result &= isRelatedTo(getFalseTypeFromConditionalType(source as ConditionalType), getFalseTypeFromConditionalType(target as ConditionalType), RecursionFlags.Both, reportErrors);
-                                }
-                                if (result) {
-                                    resetErrorInfo(saveErrorInfo);
-                                    return result;
-                                }
+                            if (result) {
+                                resetErrorInfo(saveErrorInfo);
+                                return result;
                             }
                         }
                     }
@@ -19164,18 +19191,13 @@ namespace ts {
                         }
                     }
 
-
-                    // We'll repeatedly decompose source side conditionals if they're recursive - check if we've already recured on the constraint a lot and, if so, bail
-                    // on the comparison.
-                    if (!isDeeplyNestedType(source, sourceStack, sourceDepth)) {
-                        // conditionals _can_ be related to one another via normal constraint, as, eg, `A extends B ? O : never` should be assignable to `O`
-                        // when `O` is a conditional (`never` is trivially assignable to `O`, as is `O`!).
-                        const defaultConstraint = getDefaultConstraintOfConditionalType(source as ConditionalType);
-                        if (defaultConstraint) {
-                            if (result = isRelatedTo(defaultConstraint, target, RecursionFlags.Source, reportErrors)) {
-                                resetErrorInfo(saveErrorInfo);
-                                return result;
-                            }
+                    // conditionals _can_ be related to one another via normal constraint, as, eg, `A extends B ? O : never` should be assignable to `O`
+                    // when `O` is a conditional (`never` is trivially assignable to `O`, as is `O`!).
+                    const defaultConstraint = getDefaultConstraintOfConditionalType(source as ConditionalType);
+                    if (defaultConstraint) {
+                        if (result = isRelatedTo(defaultConstraint, target, RecursionFlags.Source, reportErrors)) {
+                            resetErrorInfo(saveErrorInfo);
+                            return result;
                         }
                     }
                 }
@@ -20321,14 +20343,14 @@ namespace ts {
         // `type A<T> = null extends T ? [A<NonNullable<T>>] : [T]`
         // has expanded into `[A<NonNullable<NonNullable<NonNullable<NonNullable<NonNullable<T>>>>>>]`
         // in such cases we need to terminate the expansion, and we do so here.
-        function isDeeplyNestedType(type: Type, stack: Type[], depth: number): boolean {
-            if (depth >= 5) {
+        function isDeeplyNestedType(type: Type, stack: Type[], depth: number, maxDepth = 5): boolean {
+            if (depth >= maxDepth) {
                 const identity = getRecursionIdentity(type);
                 let count = 0;
                 for (let i = 0; i < depth; i++) {
                     if (getRecursionIdentity(stack[i]) === identity) {
                         count++;
-                        if (count >= 5) {
+                        if (count >= maxDepth) {
                             return true;
                         }
                     }
@@ -21537,6 +21559,11 @@ namespace ts {
                 undefined;
         }
 
+        function isTypeMatchedByTemplateLiteralType(source: Type, target: TemplateLiteralType): boolean {
+            const inferences = inferTypesFromTemplateLiteralType(source, target);
+            return !!inferences && every(inferences, (r, i) => isValidTypeForTemplateLiteralPlaceholder(r, target.types[i]));
+        }
+
         function getStringLikeTypeForType(type: Type) {
             return type.flags & (TypeFlags.Any | TypeFlags.StringLike) ? type : getTemplateLiteralType(["", ""], [type]);
         }
@@ -22326,12 +22353,11 @@ namespace ts {
                 if (signature) {
                     const inferredCovariantType = inference.candidates ? getCovariantInference(inference, signature) : undefined;
                     if (inference.contraCandidates) {
-                        const inferredContravariantType = getContravariantInference(inference);
                         // If we have both co- and contra-variant inferences, we prefer the contra-variant inference
-                        // unless the co-variant inference is a subtype and not 'never'.
+                        // unless the co-variant inference is a subtype of some contra-variant inference and not 'never'.
                         inferredType = inferredCovariantType && !(inferredCovariantType.flags & TypeFlags.Never) &&
-                            isTypeSubtypeOf(inferredCovariantType, inferredContravariantType) ?
-                            inferredCovariantType : inferredContravariantType;
+                            some(inference.contraCandidates, t => isTypeSubtypeOf(inferredCovariantType, t)) ?
+                            inferredCovariantType : getContravariantInference(inference);
                     }
                     else if (inferredCovariantType) {
                         inferredType = inferredCovariantType;
@@ -22652,8 +22678,9 @@ namespace ts {
         // constituent types keyed by the literal types of the property by that name in each constituent type.
         function getKeyPropertyName(unionType: UnionType): __String | undefined {
             const types = unionType.types;
-            // We only construct maps for large unions with non-primitive constituents.
-            if (types.length < 10 || getObjectFlags(unionType) & ObjectFlags.PrimitiveUnion) {
+            // We only construct maps for unions with many non-primitive constituents.
+            if (types.length < 10 || getObjectFlags(unionType) & ObjectFlags.PrimitiveUnion ||
+                countWhere(types, t => !!(t.flags & (TypeFlags.Object | TypeFlags.InstantiableNonPrimitive))) < 10) {
                 return undefined;
             }
             if (unionType.keyPropertyName === undefined) {
@@ -22687,7 +22714,7 @@ namespace ts {
             const keyPropertyName = getKeyPropertyName(unionType);
             const propNode = keyPropertyName && find(node.properties, p => p.symbol && p.kind === SyntaxKind.PropertyAssignment &&
                 p.symbol.escapedName === keyPropertyName && isPossiblyDiscriminantValue(p.initializer));
-            const propType = propNode && getTypeOfExpression((propNode as PropertyAssignment).initializer);
+            const propType = propNode && getContextFreeTypeOfExpression((propNode as PropertyAssignment).initializer);
             return propType && getConstituentTypeForKeyType(unionType, propType);
         }
 
@@ -23145,7 +23172,7 @@ namespace ts {
         }
 
         function getConstituentCount(type: Type) {
-            return type.flags & TypeFlags.UnionOrIntersection ? (type as UnionOrIntersectionType).types.length : 1;
+            return type.flags & TypeFlags.Union ? (type as UnionType).types.length : 1;
         }
 
         function extractTypesOfKind(type: Type, kind: TypeFlags) {
@@ -24731,7 +24758,7 @@ namespace ts {
             return parent.kind === SyntaxKind.PropertyAccessExpression ||
                 parent.kind === SyntaxKind.CallExpression && (parent as CallExpression).expression === node ||
                 parent.kind === SyntaxKind.ElementAccessExpression && (parent as ElementAccessExpression).expression === node &&
-                    !(isGenericTypeWithoutNullableConstraint(type) && isGenericIndexType(getTypeOfExpression((parent as ElementAccessExpression).argumentExpression)));
+                    !(someType(type, isGenericTypeWithoutNullableConstraint) && isGenericIndexType(getTypeOfExpression((parent as ElementAccessExpression).argumentExpression)));
         }
 
         function isGenericTypeWithUnionConstraint(type: Type) {
@@ -26194,7 +26221,7 @@ namespace ts {
                 concatenate(
                     map(
                         filter(node.properties, p => !!p.symbol && p.kind === SyntaxKind.JsxAttribute && isDiscriminantProperty(contextualType, p.symbol.escapedName) && (!p.initializer || isPossiblyDiscriminantValue(p.initializer))),
-                        prop => ([!(prop as JsxAttribute).initializer ? (() => trueType) : (() => checkExpression((prop as JsxAttribute).initializer!)), prop.symbol.escapedName] as [() => Type, __String])
+                        prop => ([!(prop as JsxAttribute).initializer ? (() => trueType) : (() => getContextFreeTypeOfExpression((prop as JsxAttribute).initializer!)), prop.symbol.escapedName] as [() => Type, __String])
                     ),
                     map(
                         filter(getPropertiesOfType(contextualType), s => !!(s.flags & SymbolFlags.Optional) && !!node?.symbol?.members && !node.symbol.members.has(s.escapedName) && isDiscriminantProperty(contextualType, s.escapedName)),
@@ -26807,6 +26834,10 @@ namespace ts {
         function checkComputedPropertyName(node: ComputedPropertyName): Type {
             const links = getNodeLinks(node.expression);
             if (!links.resolvedType) {
+                if ((isTypeLiteralNode(node.parent.parent) || isClassLike(node.parent.parent) || isInterfaceDeclaration(node.parent.parent))
+                    && isBinaryExpression(node.expression) && node.expression.operatorToken.kind === SyntaxKind.InKeyword) {
+                    return links.resolvedType = errorType;
+                }
                 links.resolvedType = checkExpression(node.expression);
                 // The computed property name of a non-static class field within a loop must be stored in a block-scoped binding.
                 // (It needs to be bound at class evaluation time.)
@@ -34632,7 +34663,7 @@ namespace ts {
             forEach(node.members, checkSourceElement);
             if (produceDiagnostics) {
                 const type = getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node);
-                checkIndexConstraints(type);
+                checkIndexConstraints(type, type.symbol);
                 checkTypeForDuplicateIndexSignatures(node);
                 checkObjectTypeForDuplicateDeclarations(node);
             }
@@ -34732,6 +34763,7 @@ namespace ts {
         }
 
         function checkMappedType(node: MappedTypeNode) {
+            checkGrammarMappedType(node);
             checkSourceElement(node.typeParameter);
             checkSourceElement(node.nameType);
             checkSourceElement(node.type);
@@ -34751,6 +34783,12 @@ namespace ts {
             }
         }
 
+        function checkGrammarMappedType(node: MappedTypeNode) {
+            if (node.members?.length) {
+                return grammarErrorOnNode(node.members[0], Diagnostics.A_mapped_type_may_not_declare_properties_or_methods);
+            }
+        }
+
         function checkThisType(node: ThisTypeNode) {
             getTypeFromThisTypeNode(node);
         }
@@ -38065,7 +38103,7 @@ namespace ts {
             }
         }
 
-        function checkIndexConstraints(type: Type, isStaticIndex?: boolean) {
+        function checkIndexConstraints(type: Type, symbol: Symbol, isStaticIndex?: boolean) {
             const indexInfos = getIndexInfosOfType(type);
             if (indexInfos.length === 0) {
                 return;
@@ -38075,7 +38113,7 @@ namespace ts {
                     checkIndexConstraintForProperty(type, prop, getLiteralTypeFromProperty(prop, TypeFlags.StringOrNumberLiteralOrUnique, /*includeNonPublic*/ true), getNonMissingTypeOfSymbol(prop));
                 }
             }
-            const typeDeclaration = type.symbol.valueDeclaration;
+            const typeDeclaration = symbol.valueDeclaration;
             if (typeDeclaration && isClassLike(typeDeclaration)) {
                 for (const member of typeDeclaration.members) {
                     // Only process instance properties with computed names here. Static properties cannot be in conflict with indexers,
@@ -38416,8 +38454,8 @@ namespace ts {
             }
 
             if (produceDiagnostics) {
-                checkIndexConstraints(type);
-                checkIndexConstraints(staticType, /*isStaticIndex*/ true);
+                checkIndexConstraints(type, symbol);
+                checkIndexConstraints(staticType, symbol, /*isStaticIndex*/ true);
                 checkTypeForDuplicateIndexSignatures(node);
                 checkPropertyInitialization(node);
             }
@@ -38844,7 +38882,7 @@ namespace ts {
                         for (const baseType of getBaseTypes(type)) {
                             checkTypeAssignableTo(typeWithThis, getTypeWithThisArgument(baseType, type.thisType), node.name, Diagnostics.Interface_0_incorrectly_extends_interface_1);
                         }
-                        checkIndexConstraints(type);
+                        checkIndexConstraints(type, symbol);
                     }
                 }
                 checkObjectTypeForDuplicateDeclarations(node);
@@ -43413,6 +43451,11 @@ namespace ts {
         }
 
         function checkGrammarProperty(node: PropertyDeclaration | PropertySignature) {
+            if (isComputedPropertyName(node.name) && isBinaryExpression(node.name.expression) && node.name.expression.operatorToken.kind === SyntaxKind.InKeyword) {
+                return grammarErrorOnNode(
+                    (node.parent as ClassLikeDeclaration | InterfaceDeclaration | TypeLiteralNode).members[0],
+                    Diagnostics.A_mapped_type_may_not_declare_properties_or_methods);
+            }
             if (isClassLike(node.parent)) {
                 if (isStringLiteral(node.name) && node.name.text === "constructor") {
                     return grammarErrorOnNode(node.name, Diagnostics.Classes_may_not_have_a_field_named_constructor);
@@ -43432,7 +43475,7 @@ namespace ts {
                     return grammarErrorOnNode(node.initializer, Diagnostics.An_interface_property_cannot_have_an_initializer);
                 }
             }
-            else if (node.parent.kind === SyntaxKind.TypeLiteral) {
+            else if (isTypeLiteralNode(node.parent)) {
                 if (checkGrammarForInvalidDynamicName(node.name, Diagnostics.A_computed_property_name_in_a_type_literal_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type)) {
                     return true;
                 }

src/compiler/commandLineParser.ts

@@ -1,6 +1,6 @@
 namespace ts {
     /* @internal */
-    export const compileOnSaveCommandLineOption: CommandLineOption = { name: "compileOnSave", type: "boolean" };
+    export const compileOnSaveCommandLineOption: CommandLineOption = { name: "compileOnSave", type: "boolean", defaultValueDescription: "false" };
 
     const jsxOptionMap = new Map(getEntries({
         "preserve": JsxEmit.Preserve,
@@ -144,6 +144,7 @@ namespace ts {
             type: "boolean",
             category: Diagnostics.Watch_and_Build_Modes,
             description: Diagnostics.Synchronously_call_callbacks_and_update_the_state_of_directory_watchers_on_platforms_that_don_t_support_recursive_watching_natively,
+            defaultValueDescription: "false",
         },
         {
             name: "excludeDirectories",
@@ -180,11 +181,13 @@ namespace ts {
             showInSimplifiedHelpView: true,
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Print_this_message,
+            defaultValueDescription: "false",
         },
         {
             name: "help",
             shortName: "?",
-            type: "boolean"
+            type: "boolean",
+            defaultValueDescription: "false",
         },
         {
             name: "watch",
@@ -194,6 +197,7 @@ namespace ts {
             isCommandLineOnly: true,
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Watch_input_files,
+            defaultValueDescription: "false",
         },
         {
             name: "preserveWatchOutput",
@@ -201,7 +205,7 @@ namespace ts {
             showInSimplifiedHelpView: false,
             category: Diagnostics.Output_Formatting,
             description: Diagnostics.Disable_wiping_the_console_in_watch_mode,
-            defaultValueDescription: "n/a"
+            defaultValueDescription: "false",
         },
         {
             name: "listFiles",
@@ -214,7 +218,8 @@ namespace ts {
             name: "explainFiles",
             type: "boolean",
             category: Diagnostics.Compiler_Diagnostics,
-            description: Diagnostics.Print_files_read_during_the_compilation_including_why_it_was_included
+            description: Diagnostics.Print_files_read_during_the_compilation_including_why_it_was_included,
+            defaultValueDescription: "false",
         },
         {
             name: "listEmittedFiles",
@@ -285,7 +290,8 @@ namespace ts {
             affectsSemanticDiagnostics: true,
             affectsEmit: true,
             category: Diagnostics.Watch_and_Build_Modes,
-            description: Diagnostics.Have_recompiles_in_projects_that_use_incremental_and_watch_mode_assume_that_changes_within_a_file_will_only_affect_files_directly_depending_on_it
+            description: Diagnostics.Have_recompiles_in_projects_that_use_incremental_and_watch_mode_assume_that_changes_within_a_file_will_only_affect_files_directly_depending_on_it,
+            defaultValueDescription: "false",
         },
         {
             name: "locale",
@@ -333,6 +339,7 @@ namespace ts {
             showInSimplifiedHelpView: true,
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Show_all_compiler_options,
+            defaultValueDescription: "false",
         },
         {
             name: "version",
@@ -341,6 +348,7 @@ namespace ts {
             showInSimplifiedHelpView: true,
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Print_the_compiler_s_version,
+            defaultValueDescription: "false",
         },
         {
             name: "init",
@@ -348,6 +356,7 @@ namespace ts {
             showInSimplifiedHelpView: true,
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Initializes_a_TypeScript_project_and_creates_a_tsconfig_json_file,
+            defaultValueDescription: "false",
         },
         {
             name: "project",
@@ -365,7 +374,8 @@ namespace ts {
             shortName: "b",
             showInSimplifiedHelpView: true,
             category: Diagnostics.Command_line_Options,
-            description: Diagnostics.Build_one_or_more_projects_and_their_dependencies_if_out_of_date
+            description: Diagnostics.Build_one_or_more_projects_and_their_dependencies_if_out_of_date,
+            defaultValueDescription: "false",
         },
         {
             name: "showConfig",
@@ -373,7 +383,8 @@ namespace ts {
             showInSimplifiedHelpView: true,
             category: Diagnostics.Command_line_Options,
             isCommandLineOnly: true,
-            description: Diagnostics.Print_the_final_configuration_instead_of_building
+            description: Diagnostics.Print_the_final_configuration_instead_of_building,
+            defaultValueDescription: "false",
         },
         {
             name: "listFilesOnly",
@@ -382,7 +393,8 @@ namespace ts {
             affectsSemanticDiagnostics: true,
             affectsEmit: true,
             isCommandLineOnly: true,
-            description: Diagnostics.Print_names_of_files_that_are_part_of_the_compilation_and_then_stop_processing
+            description: Diagnostics.Print_names_of_files_that_are_part_of_the_compilation_and_then_stop_processing,
+            defaultValueDescription: "false",
         },
 
         // Basic
@@ -504,7 +516,6 @@ namespace ts {
             category: Diagnostics.Emit,
             description: Diagnostics.Specify_a_file_that_bundles_all_outputs_into_one_JavaScript_file_If_declaration_is_true_also_designates_a_file_that_bundles_all_d_ts_output,
             transpileOptionValue: undefined,
-            defaultValueDescription: "n/a"
         },
         {
             name: "outDir",
@@ -515,7 +526,6 @@ namespace ts {
             showInSimplifiedHelpView: true,
             category: Diagnostics.Emit,
             description: Diagnostics.Specify_an_output_folder_for_all_emitted_files,
-            defaultValueDescription: "n/a"
         },
         {
             name: "rootDir",
@@ -673,6 +683,7 @@ namespace ts {
             strictFlag: true,
             category: Diagnostics.Type_Checking,
             description: Diagnostics.Type_catch_clause_variables_as_unknown_instead_of_any,
+            defaultValueDescription: "false",
         },
         {
             name: "alwaysStrict",
@@ -706,7 +717,8 @@ namespace ts {
             type: "boolean",
             affectsSemanticDiagnostics: true,
             category: Diagnostics.Type_Checking,
-            description: Diagnostics.Interpret_optional_property_types_as_written_rather_than_adding_undefined
+            description: Diagnostics.Interpret_optional_property_types_as_written_rather_than_adding_undefined,
+            defaultValueDescription: "false",
         },
         {
             name: "noImplicitReturns",
@@ -722,21 +734,24 @@ namespace ts {
             affectsBindDiagnostics: true,
             affectsSemanticDiagnostics: true,
             category: Diagnostics.Type_Checking,
-            description: Diagnostics.Enable_error_reporting_for_fallthrough_cases_in_switch_statements
+            description: Diagnostics.Enable_error_reporting_for_fallthrough_cases_in_switch_statements,
+            defaultValueDescription: "false",
         },
         {
             name: "noUncheckedIndexedAccess",
             type: "boolean",
             affectsSemanticDiagnostics: true,
             category: Diagnostics.Type_Checking,
-            description: Diagnostics.Include_undefined_in_index_signature_results
+            description: Diagnostics.Include_undefined_in_index_signature_results,
+            defaultValueDescription: "false",
         },
         {
             name: "noImplicitOverride",
             type: "boolean",
             affectsSemanticDiagnostics: true,
             category: Diagnostics.Type_Checking,
-            description: Diagnostics.Ensure_overriding_members_in_derived_classes_are_marked_with_an_override_modifier
+            description: Diagnostics.Ensure_overriding_members_in_derived_classes_are_marked_with_an_override_modifier,
+            defaultValueDescription: "false",
         },
         {
             name: "noPropertyAccessFromIndexSignature",
@@ -846,7 +861,7 @@ namespace ts {
             type: "boolean",
             category: Diagnostics.Interop_Constraints,
             description: Diagnostics.Disable_resolving_symlinks_to_their_realpath_This_correlates_to_the_same_flag_in_node,
-            defaultValueDescription: "n/a"
+            defaultValueDescription: "false",
         },
         {
             name: "allowUmdGlobalAccess",
@@ -897,7 +912,8 @@ namespace ts {
             type: "boolean",
             affectsSemanticDiagnostics: true,
             category: Diagnostics.Language_and_Environment,
-            description: Diagnostics.Enable_experimental_support_for_TC39_stage_2_draft_decorators
+            description: Diagnostics.Enable_experimental_support_for_TC39_stage_2_draft_decorators,
+            defaultValueDescription: "false",
         },
         {
             name: "emitDecoratorMetadata",
@@ -905,7 +921,8 @@ namespace ts {
             affectsSemanticDiagnostics: true,
             affectsEmit: true,
             category: Diagnostics.Language_and_Environment,
-            description: Diagnostics.Emit_design_type_metadata_for_decorated_declarations_in_source_files
+            description: Diagnostics.Emit_design_type_metadata_for_decorated_declarations_in_source_files,
+            defaultValueDescription: "false",
         },
 
         // Advanced
@@ -950,7 +967,6 @@ namespace ts {
             category: Diagnostics.Backwards_Compatibility,
             paramType: Diagnostics.FILE,
             transpileOptionValue: undefined,
-            defaultValueDescription: "n/a",
             description: Diagnostics.Deprecated_setting_Use_outFile_instead,
         },
         {
@@ -1031,6 +1047,7 @@ namespace ts {
             affectsEmit: true,
             category: Diagnostics.Emit,
             description: Diagnostics.Disable_emitting_declarations_that_have_internal_in_their_JSDoc_comments,
+            defaultValueDescription: "false",
         },
         {
             name: "disableSizeLimit",
@@ -1045,21 +1062,24 @@ namespace ts {
             type: "boolean",
             isTSConfigOnly: true,
             category: Diagnostics.Projects,
-            description: Diagnostics.Disable_preferring_source_files_instead_of_declaration_files_when_referencing_composite_projects
+            description: Diagnostics.Disable_preferring_source_files_instead_of_declaration_files_when_referencing_composite_projects,
+            defaultValueDescription: "false",
         },
         {
             name: "disableSolutionSearching",
             type: "boolean",
             isTSConfigOnly: true,
             category: Diagnostics.Projects,
-            description: Diagnostics.Opt_a_project_out_of_multi_project_reference_checking_when_editing
+            description: Diagnostics.Opt_a_project_out_of_multi_project_reference_checking_when_editing,
+            defaultValueDescription: "false",
         },
         {
             name: "disableReferencedProjectLoad",
             type: "boolean",
             isTSConfigOnly: true,
             category: Diagnostics.Projects,
-            description: Diagnostics.Reduce_the_number_of_projects_loaded_automatically_by_TypeScript
+            description: Diagnostics.Reduce_the_number_of_projects_loaded_automatically_by_TypeScript,
+            defaultValueDescription: "false",
         },
         {
             name: "noImplicitUseStrict",
@@ -1092,7 +1112,7 @@ namespace ts {
             affectsEmit: true,
             category: Diagnostics.Emit,
             description: Diagnostics.Disable_erasing_const_enum_declarations_in_generated_code,
-            defaultValueDescription: "n/a"
+            defaultValueDescription: "false",
         },
         {
             name: "declarationDir",
@@ -1103,7 +1123,6 @@ namespace ts {
             category: Diagnostics.Emit,
             transpileOptionValue: undefined,
             description: Diagnostics.Specify_the_output_directory_for_generated_declaration_files,
-            defaultValueDescription: "n/a"
         },
         {
             name: "skipLibCheck",
@@ -1185,6 +1204,7 @@ namespace ts {
             affectsEmit: true,
             category: Diagnostics.Emit,
             description: Diagnostics.Preserve_unused_imported_values_in_the_JavaScript_output_that_would_otherwise_be_removed,
+            defaultValueDescription: "false",
         },
 
         {
@@ -1247,27 +1267,31 @@ namespace ts {
             shortName: "v",
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Enable_verbose_logging,
-            type: "boolean"
+            type: "boolean",
+            defaultValueDescription: "false",
         },
         {
             name: "dry",
             shortName: "d",
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Show_what_would_be_built_or_deleted_if_specified_with_clean,
-            type: "boolean"
+            type: "boolean",
+            defaultValueDescription: "false",
         },
         {
             name: "force",
             shortName: "f",
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Build_all_projects_including_those_that_appear_to_be_up_to_date,
-            type: "boolean"
+            type: "boolean",
+            defaultValueDescription: "false",
         },
         {
             name: "clean",
             category: Diagnostics.Command_line_Options,
             description: Diagnostics.Delete_the_outputs_of_all_projects,
-            type: "boolean"
+            type: "boolean",
+            defaultValueDescription: "false",
         }
     ];
 
@@ -1285,10 +1309,12 @@ namespace ts {
              */
             name: "enableAutoDiscovery",
             type: "boolean",
+            defaultValueDescription: "false",
         },
         {
             name: "enable",
             type: "boolean",
+            defaultValueDescription: "false",
         },
         {
             name: "include",
@@ -1309,6 +1335,7 @@ namespace ts {
         {
             name: "disableFilenameBasedTypeAcquisition",
             type: "boolean",
+            defaultValueDescription: "false",
         },
     ];
 
@@ -2290,7 +2317,7 @@ namespace ts {
             return getCustomTypeMapOfCommandLineOption(optionDefinition.element);
         }
         else {
-            return (optionDefinition as CommandLineOptionOfCustomType).type;
+            return optionDefinition.type;
         }
     }
 

src/compiler/core.ts

@@ -1,25 +1,5 @@
 /* @internal */
 namespace ts {
-    type GetIteratorCallback = <I extends readonly any[] | ReadonlySet<any> | ReadonlyESMap<any, any> | undefined>(iterable: I) => Iterator<
-        I extends ReadonlyESMap<infer K, infer V> ? [K, V] :
-        I extends ReadonlySet<infer T> ? T :
-        I extends readonly (infer T)[] ? T :
-        I extends undefined ? undefined :
-        never>;
-
-    function getCollectionImplementation<
-        K1 extends MatchingKeys<typeof NativeCollections, () => any>,
-        K2 extends MatchingKeys<typeof ShimCollections, (getIterator?: GetIteratorCallback) => ReturnType<(typeof NativeCollections)[K1]>>
-    >(name: string, nativeFactory: K1, shimFactory: K2): NonNullable<ReturnType<(typeof NativeCollections)[K1]>> {
-        // NOTE: ts.ShimCollections will be defined for typescriptServices.js but not for tsc.js, so we must test for it.
-        const constructor = NativeCollections[nativeFactory]() ?? ShimCollections?.[shimFactory](getIterator);
-        if (constructor) return constructor as NonNullable<ReturnType<(typeof NativeCollections)[K1]>>;
-        throw new Error(`TypeScript requires an environment that provides a compatible native ${name} implementation.`);
-    }
-
-    export const Map = getCollectionImplementation("Map", "tryGetNativeMap", "createMapShim");
-    export const Set = getCollectionImplementation("Set", "tryGetNativeSet", "createSetShim");
-
     export function getIterator<I extends readonly any[] | ReadonlySet<any> | ReadonlyESMap<any, any> | undefined>(iterable: I): Iterator<
         I extends ReadonlyESMap<infer K, infer V> ? [K, V] :
         I extends ReadonlySet<infer T> ? T :

src/compiler/corePublic.ts

@@ -113,7 +113,7 @@ namespace ts {
     }
 
     /* @internal */
-    export namespace NativeCollections {
+    namespace NativeCollections {
         declare const Map: MapConstructor | undefined;
         declare const Set: SetConstructor | undefined;
 
@@ -135,4 +135,28 @@ namespace ts {
             return typeof Set !== "undefined" && "entries" in Set.prototype && new Set([0]).size === 1 ? Set : undefined;
         }
     }
-}
+
+    /* @internal */
+    export const Map = getCollectionImplementation("Map", "tryGetNativeMap", "createMapShim");
+    /* @internal */
+    export const Set = getCollectionImplementation("Set", "tryGetNativeSet", "createSetShim");
+
+    /* @internal */
+    type GetIteratorCallback = <I extends readonly any[] | ReadonlySet<any> | ReadonlyESMap<any, any> | undefined>(iterable: I) => Iterator<
+        I extends ReadonlyESMap<infer K, infer V> ? [K, V] :
+        I extends ReadonlySet<infer T> ? T :
+        I extends readonly (infer T)[] ? T :
+        I extends undefined ? undefined :
+        never>;
+
+    /* @internal */
+    function getCollectionImplementation<
+        K1 extends MatchingKeys<typeof NativeCollections, () => any>,
+        K2 extends MatchingKeys<typeof ShimCollections, (getIterator?: GetIteratorCallback) => ReturnType<(typeof NativeCollections)[K1]>>
+    >(name: string, nativeFactory: K1, shimFactory: K2): NonNullable<ReturnType<(typeof NativeCollections)[K1]>> {
+        // NOTE: ts.ShimCollections will be defined for typescriptServices.js but not for tsc.js, so we must test for it.
+        const constructor = NativeCollections[nativeFactory]() ?? ShimCollections?.[shimFactory](getIterator);
+        if (constructor) return constructor as NonNullable<ReturnType<(typeof NativeCollections)[K1]>>;
+        throw new Error(`TypeScript requires an environment that provides a compatible native ${name} implementation.`);
+    }
+}

src/compiler/diagnosticMessages.json

@@ -1164,6 +1164,10 @@
         "category": "Error",
         "code": 1389
     },
+    "'{0}' is not allowed as a parameter name.": {
+        "category": "Error",
+        "code": 1390
+    },
     "An import alias cannot use 'import type'": {
         "category": "Error",
         "code": 1392
@@ -5993,7 +5997,10 @@
         "category": "Error",
         "code": 7060
     },
-
+    "A mapped type may not declare properties or methods.": {
+        "category": "Error",
+        "code": 7061
+    },
 
     "You cannot rename this element.": {
         "category": "Error",
@@ -6216,7 +6223,7 @@
         "code": 18003
     },
 
-    "File is a CommonJS module; it may be converted to an ES6 module.": {
+    "File is a CommonJS module; it may be converted to an ES module.": {
         "category": "Suggestion",
         "code": 80001
     },
@@ -6465,7 +6472,7 @@
         "category": "Message",
         "code": 95016
     },
-    "Convert to ES6 module": {
+    "Convert to ES module": {
         "category": "Message",
         "code": 95017
     },

src/compiler/factory/nodeFactory.ts

@@ -2112,25 +2112,27 @@ namespace ts {
         }
 
         // @api
-        function createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode {
+        function createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: readonly TypeElement[] | undefined): MappedTypeNode {
             const node = createBaseNode<MappedTypeNode>(SyntaxKind.MappedType);
             node.readonlyToken = readonlyToken;
             node.typeParameter = typeParameter;
             node.nameType = nameType;
             node.questionToken = questionToken;
             node.type = type;
+            node.members = members && createNodeArray(members);
             node.transformFlags = TransformFlags.ContainsTypeScript;
             return node;
         }
 
         // @api
-        function updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode {
+        function updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode {
             return node.readonlyToken !== readonlyToken
                 || node.typeParameter !== typeParameter
                 || node.nameType !== nameType
                 || node.questionToken !== questionToken
                 || node.type !== type
-                ? update(createMappedTypeNode(readonlyToken, typeParameter, nameType, questionToken, type), node)
+                || node.members !== members
+                ? update(createMappedTypeNode(readonlyToken, typeParameter, nameType, questionToken, type, members), node)
                 : node;
         }
 

src/compiler/parser.ts

@@ -212,7 +212,8 @@ namespace ts {
                     visitNode(cbNode, (node as MappedTypeNode).typeParameter) ||
                     visitNode(cbNode, (node as MappedTypeNode).nameType) ||
                     visitNode(cbNode, (node as MappedTypeNode).questionToken) ||
-                    visitNode(cbNode, (node as MappedTypeNode).type);
+                    visitNode(cbNode, (node as MappedTypeNode).type) ||
+                    visitNodes(cbNode, cbNodes, (node as MappedTypeNode).members);
             case SyntaxKind.LiteralType:
                 return visitNode(cbNode, (node as LiteralTypeNode).literal);
             case SyntaxKind.NamedTupleMember:
@@ -2610,7 +2611,10 @@ namespace ts {
                 case ParsingContext.ObjectLiteralMembers: return parseErrorAtCurrentToken(Diagnostics.Property_assignment_expected);
                 case ParsingContext.ArrayLiteralMembers: return parseErrorAtCurrentToken(Diagnostics.Expression_or_comma_expected);
                 case ParsingContext.JSDocParameters: return parseErrorAtCurrentToken(Diagnostics.Parameter_declaration_expected);
-                case ParsingContext.Parameters: return parseErrorAtCurrentToken(Diagnostics.Parameter_declaration_expected);
+                case ParsingContext.Parameters:
+                    return isKeyword(token())
+                        ? parseErrorAtCurrentToken(Diagnostics._0_is_not_allowed_as_a_parameter_name, tokenToString(token()))
+                        : parseErrorAtCurrentToken(Diagnostics.Parameter_declaration_expected);
                 case ParsingContext.TypeParameters: return parseErrorAtCurrentToken(Diagnostics.Type_parameter_declaration_expected);
                 case ParsingContext.TypeArguments: return parseErrorAtCurrentToken(Diagnostics.Type_argument_expected);
                 case ParsingContext.TupleElementTypes: return parseErrorAtCurrentToken(Diagnostics.Type_expected);
@@ -3534,8 +3538,9 @@ namespace ts {
             }
             const type = parseTypeAnnotation();
             parseSemicolon();
+            const members = parseList(ParsingContext.TypeMembers, parseTypeMember);
             parseExpected(SyntaxKind.CloseBraceToken);
-            return finishNode(factory.createMappedTypeNode(readonlyToken, typeParameter, nameType, questionToken, type), pos);
+            return finishNode(factory.createMappedTypeNode(readonlyToken, typeParameter, nameType, questionToken, type, members), pos);
         }
 
         function parseTupleElementType() {
@@ -7277,19 +7282,24 @@ namespace ts {
             const pos = getNodePos();
             parseExpected(SyntaxKind.AssertKeyword);
             const openBracePosition = scanner.getTokenPos();
-            parseExpected(SyntaxKind.OpenBraceToken);
-            const multiLine = scanner.hasPrecedingLineBreak();
-            const elements = parseDelimitedList(ParsingContext.AssertEntries, parseAssertEntry, /*considerSemicolonAsDelimiter*/ true);
-            if (!parseExpected(SyntaxKind.CloseBraceToken)) {
-                const lastError = lastOrUndefined(parseDiagnostics);
-                if (lastError && lastError.code === Diagnostics._0_expected.code) {
-                    addRelatedInfo(
-                        lastError,
-                        createDetachedDiagnostic(fileName, openBracePosition, 1, Diagnostics.The_parser_expected_to_find_a_to_match_the_token_here)
-                    );
+            if (parseExpected(SyntaxKind.OpenBraceToken)) {
+                const multiLine = scanner.hasPrecedingLineBreak();
+                const elements = parseDelimitedList(ParsingContext.AssertEntries, parseAssertEntry, /*considerSemicolonAsDelimiter*/ true);
+                if (!parseExpected(SyntaxKind.CloseBraceToken)) {
+                    const lastError = lastOrUndefined(parseDiagnostics);
+                    if (lastError && lastError.code === Diagnostics._0_expected.code) {
+                        addRelatedInfo(
+                            lastError,
+                            createDetachedDiagnostic(fileName, openBracePosition, 1, Diagnostics.The_parser_expected_to_find_a_to_match_the_token_here)
+                        );
+                    }
                 }
+                return finishNode(factory.createAssertClause(elements, multiLine), pos);
+            }
+            else {
+                const elements = createNodeArray([], getNodePos(), /*end*/ undefined, /*hasTrailingComma*/ false);
+                return finishNode(factory.createAssertClause(elements, /*multiLine*/ false), pos);
             }
-            return finishNode(factory.createAssertClause(elements, multiLine), pos);
         }
 
         function tokenAfterImportDefinitelyProducesImportDeclaration() {
@@ -8256,8 +8266,9 @@ namespace ts {
                 }
 
                 function parseSeeTag(start: number, tagName: Identifier, indent?: number, indentText?: string): JSDocSeeTag {
-                    const isLink = lookAhead(() => nextTokenJSDoc() === SyntaxKind.AtToken && tokenIsIdentifierOrKeyword(nextTokenJSDoc()) && scanner.getTokenValue() === "link");
-                    const nameExpression = isLink ? undefined : parseJSDocNameReference();
+                    const isMarkdownOrJSDocLink = token() === SyntaxKind.OpenBracketToken
+                        || lookAhead(() => nextTokenJSDoc() === SyntaxKind.AtToken && tokenIsIdentifierOrKeyword(nextTokenJSDoc()) && scanner.getTokenValue() === "link");
+                    const nameExpression = isMarkdownOrJSDocLink ? undefined : parseJSDocNameReference();
                     const comments = indent !== undefined && indentText !== undefined ? parseTrailingTagComments(start, getNodePos(), indent, indentText) : undefined;
                     return finishNode(factory.createJSDocSeeTag(tagName, nameExpression, comments), start);
                 }

src/compiler/program.ts

@@ -685,7 +685,7 @@ namespace ts {
                 break;
             case FileIncludeKind.TypeReferenceDirective:
                 ({ pos, end } = file.typeReferenceDirectives[index]);
-                packageId = file.resolvedTypeReferenceDirectiveNames?.get(toFileNameLowerCase(file.typeReferenceDirectives[index].fileName), getModeForResolutionAtIndex(file, index))?.packageId;
+                packageId = file.resolvedTypeReferenceDirectiveNames?.get(toFileNameLowerCase(file.typeReferenceDirectives[index].fileName), file.impliedNodeFormat)?.packageId;
                 break;
             case FileIncludeKind.LibReferenceDirective:
                 ({ pos, end } = file.libReferenceDirectives[index]);

src/compiler/sys.ts

@@ -1900,6 +1900,11 @@ namespace ts {
         return sys!;
     })();
 
+    /*@internal*/
+    export function setSys(s: System) {
+        sys = s;
+    }
+
     if (sys && sys.getEnvironmentVariable) {
         setCustomPollingValues(sys);
         Debug.setAssertionLevel(/^development$/i.test(sys.getEnvironmentVariable("NODE_ENV"))

src/compiler/transformer.ts

@@ -566,7 +566,7 @@ namespace ts {
     }
 
     export const nullTransformationContext: TransformationContext = {
-        factory,
+        factory: factory, // eslint-disable-line object-shorthand
         getCompilerOptions: () => ({}),
         getEmitResolver: notImplemented,
         getEmitHost: notImplemented,

src/compiler/transformers/es2015.ts

@@ -4102,86 +4102,22 @@ namespace ts {
          * @param node A TemplateExpression node.
          */
         function visitTemplateExpression(node: TemplateExpression): Expression {
-            const expressions: Expression[] = [];
-            addTemplateHead(expressions, node);
-            addTemplateSpans(expressions, node);
-
-            // createAdd will check if each expression binds less closely than binary '+'.
-            // If it does, it wraps the expression in parentheses. Otherwise, something like
-            //    `abc${ 1 << 2 }`
-            // becomes
-            //    "abc" + 1 << 2 + ""
-            // which is really
-            //    ("abc" + 1) << (2 + "")
-            // rather than
-            //    "abc" + (1 << 2) + ""
-            const expression = reduceLeft(expressions, factory.createAdd)!;
-            if (nodeIsSynthesized(expression)) {
-                setTextRange(expression, node);
-            }
-
-            return expression;
-        }
-
-        /**
-         * Gets a value indicating whether we need to include the head of a TemplateExpression.
-         *
-         * @param node A TemplateExpression node.
-         */
-        function shouldAddTemplateHead(node: TemplateExpression) {
-            // If this expression has an empty head literal and the first template span has a non-empty
-            // literal, then emitting the empty head literal is not necessary.
-            //     `${ foo } and ${ bar }`
-            // can be emitted as
-            //     foo + " and " + bar
-            // This is because it is only required that one of the first two operands in the emit
-            // output must be a string literal, so that the other operand and all following operands
-            // are forced into strings.
-            //
-            // If the first template span has an empty literal, then the head must still be emitted.
-            //     `${ foo }${ bar }`
-            // must still be emitted as
-            //     "" + foo + bar
-
-            // There is always atleast one templateSpan in this code path, since
-            // NoSubstitutionTemplateLiterals are directly emitted via emitLiteral()
-            Debug.assert(node.templateSpans.length !== 0);
-
-            return node.head.text.length !== 0 || node.templateSpans[0].literal.text.length === 0;
-        }
-
-        /**
-         * Adds the head of a TemplateExpression to an array of expressions.
-         *
-         * @param expressions An array of expressions.
-         * @param node A TemplateExpression node.
-         */
-        function addTemplateHead(expressions: Expression[], node: TemplateExpression): void {
-            if (!shouldAddTemplateHead(node)) {
-                return;
-            }
-
-            expressions.push(factory.createStringLiteral(node.head.text));
-        }
-
-        /**
-         * Visits and adds the template spans of a TemplateExpression to an array of expressions.
-         *
-         * @param expressions An array of expressions.
-         * @param node A TemplateExpression node.
-         */
-        function addTemplateSpans(expressions: Expression[], node: TemplateExpression): void {
+            let expression: Expression = factory.createStringLiteral(node.head.text);
             for (const span of node.templateSpans) {
-                expressions.push(visitNode(span.expression, visitor, isExpression));
+                const args = [visitNode(span.expression, visitor, isExpression)];
 
-                // Only emit if the literal is non-empty.
-                // The binary '+' operator is left-associative, so the first string concatenation
-                // with the head will force the result up to this point to be a string.
-                // Emitting a '+ ""' has no semantic effect for middles and tails.
-                if (span.literal.text.length !== 0) {
-                    expressions.push(factory.createStringLiteral(span.literal.text));
+                if (span.literal.text.length > 0) {
+                    args.push(factory.createStringLiteral(span.literal.text));
                 }
+
+                expression = factory.createCallExpression(
+                    factory.createPropertyAccessExpression(expression, "concat"),
+                    /*typeArguments*/ undefined,
+                    args,
+                );
             }
+
+            return setTextRange(expression, node);
         }
 
         /**

src/compiler/transformers/jsx.ts

@@ -200,59 +200,27 @@ namespace ts {
         }
 
         function convertJsxChildrenToChildrenPropObject(children: readonly JsxChild[]) {
+            const prop = convertJsxChildrenToChildrenPropAssignment(children);
+            return prop && factory.createObjectLiteralExpression([prop]);
+        }
+
+        function convertJsxChildrenToChildrenPropAssignment(children: readonly JsxChild[]) {
             const nonWhitespaceChildren = getSemanticJsxChildren(children);
             if (length(nonWhitespaceChildren) === 1) {
                 const result = transformJsxChildToExpression(nonWhitespaceChildren[0]);
-                return result && factory.createObjectLiteralExpression([
-                    factory.createPropertyAssignment("children", result)
-                ]);
+                return result && factory.createPropertyAssignment("children", result);
             }
             const result = mapDefined(children, transformJsxChildToExpression);
-            return !result.length ? undefined : factory.createObjectLiteralExpression([
-                factory.createPropertyAssignment("children", factory.createArrayLiteralExpression(result))
-            ]);
+            return length(result) ? factory.createPropertyAssignment("children", factory.createArrayLiteralExpression(result)) : undefined;
         }
 
         function visitJsxOpeningLikeElementJSX(node: JsxOpeningLikeElement, children: readonly JsxChild[] | undefined, isChild: boolean, location: TextRange) {
             const tagName = getTagName(node);
-            let objectProperties: Expression;
+            const childrenProp = children && children.length ? convertJsxChildrenToChildrenPropAssignment(children) : undefined;
             const keyAttr = find(node.attributes.properties, p => !!p.name && isIdentifier(p.name) && p.name.escapedText === "key") as JsxAttribute | undefined;
             const attrs = keyAttr ? filter(node.attributes.properties, p => p !== keyAttr) : node.attributes.properties;
-
-            let segments: Expression[] = [];
-            if (attrs.length) {
-                // Map spans of JsxAttribute nodes into object literals and spans
-                // of JsxSpreadAttribute nodes into expressions.
-                segments = flatten(
-                    spanMap(attrs, isJsxSpreadAttribute, (attrs, isSpread) => isSpread
-                        ? map(attrs, transformJsxSpreadAttributeToExpression)
-                        : factory.createObjectLiteralExpression(map(attrs, transformJsxAttributeToObjectLiteralElement))
-                    )
-                );
-
-                if (isJsxSpreadAttribute(attrs[0])) {
-                    // We must always emit at least one object literal before a spread
-                    // argument.factory.createObjectLiteral
-                    segments.unshift(factory.createObjectLiteralExpression());
-                }
-            }
-            if (children && children.length) {
-                const result = convertJsxChildrenToChildrenPropObject(children);
-                if (result) {
-                    segments.push(result);
-                }
-            }
-
-            if (segments.length === 0) {
-                objectProperties = factory.createObjectLiteralExpression([]);
-                // When there are no attributes, React wants {}
-            }
-            else {
-                // Either emit one big object literal (no spread attribs), or
-                // a call to the __assign helper.
-                objectProperties = singleOrUndefined(segments) || emitHelpers().createAssignHelper(segments);
-            }
-
+            const objectProperties = length(attrs) ? transformJsxAttributesToObjectProps(attrs, childrenProp) :
+                factory.createObjectLiteralExpression(childrenProp ? [childrenProp] : emptyArray); // When there are no attributes, React wants {}
             return visitJsxOpeningLikeElementOrFragmentJSX(tagName, objectProperties, keyAttr, length(getSemanticJsxChildren(children || emptyArray)), isChild, location);
         }
 
@@ -285,47 +253,9 @@ namespace ts {
 
         function visitJsxOpeningLikeElementCreateElement(node: JsxOpeningLikeElement, children: readonly JsxChild[] | undefined, isChild: boolean, location: TextRange) {
             const tagName = getTagName(node);
-            let objectProperties: Expression | undefined;
             const attrs = node.attributes.properties;
-            if (attrs.length === 0) {
-                objectProperties = factory.createNull();
-                // When there are no attributes, React wants "null"
-            }
-            else {
-                const target = getEmitScriptTarget(compilerOptions);
-                if (target && target >= ScriptTarget.ES2018) {
-                    objectProperties = factory.createObjectLiteralExpression(
-                        flatten<SpreadAssignment | PropertyAssignment>(
-                            spanMap(attrs, isJsxSpreadAttribute, (attrs, isSpread) =>
-                                isSpread ? map(attrs, transformJsxSpreadAttributeToSpreadAssignment) : map(attrs, transformJsxAttributeToObjectLiteralElement)
-                            )
-                        )
-                    );
-                }
-                else {
-                    // Map spans of JsxAttribute nodes into object literals and spans
-                    // of JsxSpreadAttribute nodes into expressions.
-                    const segments = flatten<Expression | ObjectLiteralExpression>(
-                        spanMap(attrs, isJsxSpreadAttribute, (attrs, isSpread) => isSpread
-                            ? map(attrs, transformJsxSpreadAttributeToExpression)
-                            : factory.createObjectLiteralExpression(map(attrs, transformJsxAttributeToObjectLiteralElement))
-                        )
-                    );
-
-                    if (isJsxSpreadAttribute(attrs[0])) {
-                        // We must always emit at least one object literal before a spread
-                        // argument.factory.createObjectLiteral
-                        segments.unshift(factory.createObjectLiteralExpression());
-                    }
-
-                    // Either emit one big object literal (no spread attribs), or
-                    // a call to the __assign helper.
-                    objectProperties = singleOrUndefined(segments);
-                    if (!objectProperties) {
-                        objectProperties = emitHelpers().createAssignHelper(segments);
-                    }
-                }
-            }
+            const objectProperties = length(attrs) ? transformJsxAttributesToObjectProps(attrs) :
+                factory.createNull(); // When there are no attributes, React wants "null"
 
             const callee = currentFileState.importSpecifier === undefined
                 ? createJsxFactoryExpression(
@@ -392,6 +322,44 @@ namespace ts {
             return factory.createSpreadAssignment(visitNode(node.expression, visitor, isExpression));
         }
 
+        function transformJsxAttributesToObjectProps(attrs: readonly(JsxSpreadAttribute | JsxAttribute)[], children?: PropertyAssignment) {
+            const target = getEmitScriptTarget(compilerOptions);
+            return target && target >= ScriptTarget.ES2018 ? factory.createObjectLiteralExpression(transformJsxAttributesToProps(attrs, children)) :
+                transformJsxAttributesToExpression(attrs, children);
+        }
+
+        function transformJsxAttributesToProps(attrs: readonly(JsxSpreadAttribute | JsxAttribute)[], children?: PropertyAssignment) {
+            const props = flatten<SpreadAssignment | PropertyAssignment>(spanMap(attrs, isJsxSpreadAttribute, (attrs, isSpread) =>
+                map(attrs, attr => isSpread ? transformJsxSpreadAttributeToSpreadAssignment(attr as JsxSpreadAttribute) : transformJsxAttributeToObjectLiteralElement(attr as JsxAttribute))));
+            if (children) {
+                props.push(children);
+            }
+            return props;
+        }
+
+        function transformJsxAttributesToExpression(attrs: readonly(JsxSpreadAttribute | JsxAttribute)[], children?: PropertyAssignment) {
+            // Map spans of JsxAttribute nodes into object literals and spans
+            // of JsxSpreadAttribute nodes into expressions.
+            const expressions = flatten(
+                spanMap(attrs, isJsxSpreadAttribute, (attrs, isSpread) => isSpread
+                    ? map(attrs, transformJsxSpreadAttributeToExpression)
+                    : factory.createObjectLiteralExpression(map(attrs, transformJsxAttributeToObjectLiteralElement))
+                )
+            );
+
+            if (isJsxSpreadAttribute(attrs[0])) {
+                // We must always emit at least one object literal before a spread
+                // argument.factory.createObjectLiteral
+                expressions.unshift(factory.createObjectLiteralExpression());
+            }
+
+            if (children) {
+                expressions.push(factory.createObjectLiteralExpression([children]));
+            }
+
+            return singleOrUndefined(expressions) || emitHelpers().createAssignHelper(expressions);
+        }
+
         function transformJsxSpreadAttributeToExpression(node: JsxSpreadAttribute) {
             return visitNode(node.expression, visitor, isExpression);
         }

src/compiler/types.ts

@@ -1707,6 +1707,8 @@ namespace ts {
         readonly nameType?: TypeNode;
         readonly questionToken?: QuestionToken | PlusToken | MinusToken;
         readonly type?: TypeNode;
+        /** Used only to produce grammar errors */
+        readonly members?: NodeArray<TypeElement>;
     }
 
     export interface LiteralTypeNode extends TypeNode {
@@ -6339,8 +6341,20 @@ namespace ts {
     }
 
     /* @internal */
-    export interface CommandLineOptionOfPrimitiveType extends CommandLineOptionBase {
-        type: "string" | "number" | "boolean";
+    export interface CommandLineOptionOfStringType extends CommandLineOptionBase {
+        type: "string";
+    }
+
+    /* @internal */
+    export interface CommandLineOptionOfNumberType extends CommandLineOptionBase {
+        type: "number";
+        defaultValueDescription: `${number | undefined}` | DiagnosticMessage;
+    }
+
+    /* @internal */
+    export interface CommandLineOptionOfBooleanType extends CommandLineOptionBase {
+        type: "boolean";
+        defaultValueDescription: `${boolean | undefined}` | DiagnosticMessage;
     }
 
     /* @internal */
@@ -6372,11 +6386,11 @@ namespace ts {
     /* @internal */
     export interface CommandLineOptionOfListType extends CommandLineOptionBase {
         type: "list";
-        element: CommandLineOptionOfCustomType | CommandLineOptionOfPrimitiveType | TsConfigOnlyOption;
+        element: CommandLineOptionOfCustomType | CommandLineOptionOfStringType | CommandLineOptionOfNumberType | CommandLineOptionOfBooleanType | TsConfigOnlyOption;
     }
 
     /* @internal */
-    export type CommandLineOption = CommandLineOptionOfCustomType | CommandLineOptionOfPrimitiveType | TsConfigOnlyOption | CommandLineOptionOfListType;
+    export type CommandLineOption = CommandLineOptionOfCustomType | CommandLineOptionOfStringType | CommandLineOptionOfNumberType | CommandLineOptionOfBooleanType | TsConfigOnlyOption | CommandLineOptionOfListType;
 
     /* @internal */
     export const enum CharacterCodes {
@@ -7215,8 +7229,8 @@ namespace ts {
         updateTypeOperatorNode(node: TypeOperatorNode, type: TypeNode): TypeOperatorNode;
         createIndexedAccessTypeNode(objectType: TypeNode, indexType: TypeNode): IndexedAccessTypeNode;
         updateIndexedAccessTypeNode(node: IndexedAccessTypeNode, objectType: TypeNode, indexType: TypeNode): IndexedAccessTypeNode;
-        createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode;
-        updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode;
+        createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode;
+        updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode;
         createLiteralTypeNode(literal: LiteralTypeNode["literal"]): LiteralTypeNode;
         updateLiteralTypeNode(node: LiteralTypeNode, literal: LiteralTypeNode["literal"]): LiteralTypeNode;
         createTemplateLiteralType(head: TemplateHead, templateSpans: readonly TemplateLiteralTypeSpan[]): TemplateLiteralTypeNode;

src/compiler/utilities.ts

@@ -6627,7 +6627,7 @@ namespace ts {
             includeFilePattern: getRegularExpressionForWildcard(includes, absolutePath, "files"),
             includeDirectoryPattern: getRegularExpressionForWildcard(includes, absolutePath, "directories"),
             excludePattern: getRegularExpressionForWildcard(excludes, absolutePath, "exclude"),
-            basePaths: getBasePaths(path, includes, useCaseSensitiveFileNames)
+            basePaths: getBasePaths(absolutePath, includes, useCaseSensitiveFileNames)
         };
     }
 
@@ -6651,22 +6651,22 @@ namespace ts {
         const results: string[][] = includeFileRegexes ? includeFileRegexes.map(() => []) : [[]];
         const visited = new Map<string, true>();
         const toCanonical = createGetCanonicalFileName(useCaseSensitiveFileNames);
-        for (const basePath of patterns.basePaths) {
-            if (directoryExists(basePath)) {
-                visitDirectory(basePath, combinePaths(currentDirectory, basePath), depth);
+        for (const absoluteBasePath of patterns.basePaths) {
+            if (directoryExists(absoluteBasePath)) {
+                visitDirectory(absoluteBasePath, depth);
             }
         }
 
         return flatten(results);
 
-        function visitDirectory(path: string, absolutePath: string, depth: number | undefined) {
+        function visitDirectory(absolutePath: string, depth: number | undefined) {
             const canonicalPath = toCanonical(realpath(absolutePath));
             if (visited.has(canonicalPath)) return;
             visited.set(canonicalPath, true);
-            const { files, directories } = getFileSystemEntries(path);
+            const { files, directories } = getFileSystemEntries(absolutePath);
 
             for (const current of sort<string>(files, compareStringsCaseSensitive)) {
-                const name = combinePaths(path, current);
+                const name = combinePaths(absolutePath, current);
                 const absoluteName = combinePaths(absolutePath, current);
                 if (extensions && !fileExtensionIsOneOf(name, extensions)) continue;
                 if (excludeRegex && excludeRegex.test(absoluteName)) continue;
@@ -6689,11 +6689,10 @@ namespace ts {
             }
 
             for (const current of sort<string>(directories, compareStringsCaseSensitive)) {
-                const name = combinePaths(path, current);
                 const absoluteName = combinePaths(absolutePath, current);
                 if ((!includeDirectoryRegex || includeDirectoryRegex.test(absoluteName)) &&
                     (!excludeRegex || !excludeRegex.test(absoluteName))) {
-                    visitDirectory(name, absoluteName, depth);
+                    visitDirectory(absoluteName, depth);
                 }
             }
         }
@@ -6701,10 +6700,11 @@ namespace ts {
 
     /**
      * Computes the unique non-wildcard base paths amongst the provided include patterns.
+     * @returns Absolute directory paths
      */
-    function getBasePaths(path: string, includes: readonly string[] | undefined, useCaseSensitiveFileNames: boolean): string[] {
+    function getBasePaths(absoluteTsconfigPath: string, includes: readonly string[] | undefined, useCaseSensitiveFileNames: boolean): string[] {
         // Storage for our results in the form of literal paths (e.g. the paths as written by the user).
-        const basePaths: string[] = [path];
+        const basePaths: string[] = [absoluteTsconfigPath];
 
         if (includes) {
             // Storage for literal base paths amongst the include patterns.
@@ -6712,9 +6712,9 @@ namespace ts {
             for (const include of includes) {
                 // We also need to check the relative paths by converting them to absolute and normalizing
                 // in case they escape the base path (e.g "..\somedirectory")
-                const absolute: string = isRootedDiskPath(include) ? include : normalizePath(combinePaths(path, include));
+                const absoluteIncludePath: string = isRootedDiskPath(include) ? include : normalizePath(combinePaths(absoluteTsconfigPath, include));
                 // Append the literal and canonical candidate base paths.
-                includeBasePaths.push(getIncludeBasePath(absolute));
+                includeBasePaths.push(getIncludeBasePath(absoluteIncludePath));
             }
 
             // Sort the offsets array using either the literal or canonical path representations.
@@ -6723,7 +6723,7 @@ namespace ts {
             // Iterate over each include base path and include unique base paths that are not a
             // subpath of an existing base path
             for (const includeBasePath of includeBasePaths) {
-                if (every(basePaths, basePath => !containsPath(basePath, includeBasePath, path, !useCaseSensitiveFileNames))) {
+                if (every(basePaths, basePath => !containsPath(basePath, includeBasePath, absoluteTsconfigPath, !useCaseSensitiveFileNames))) {
                     basePaths.push(includeBasePath);
                 }
             }

src/compiler/visitorPublic.ts

@@ -629,7 +629,8 @@ namespace ts {
                     nodeVisitor(node.typeParameter, visitor, isTypeParameterDeclaration),
                     nodeVisitor(node.nameType, visitor, isTypeNode),
                     nodeVisitor(node.questionToken, tokenVisitor, isQuestionOrPlusOrMinusToken),
-                    nodeVisitor(node.type, visitor, isTypeNode));
+                    nodeVisitor(node.type, visitor, isTypeNode),
+                    nodesVisitor(node.members, visitor, isTypeElement));
 
             case SyntaxKind.LiteralType:
                 Debug.type<LiteralTypeNode>(node);

src/compiler/watchPublic.ts

@@ -560,6 +560,9 @@ namespace ts {
                         sourceFilesCache.set(path, false);
                     }
                 }
+                if (sourceFile) {
+                    sourceFile.impliedNodeFormat = getImpliedNodeFormatForFile(path, resolutionCache.getModuleResolutionCache().getPackageJsonInfoCache(), compilerHost, compilerHost.getCompilationSettings());
+                }
                 return sourceFile;
             }
             return hostSourceFile.sourceFile;

src/harness/findUpDir.ts

@@ -0,0 +1,21 @@
+namespace findUpDir {
+    import { join, resolve, dirname } from "path";
+    import { existsSync } from "fs";
+
+    // search directories upward to avoid hard-wired paths based on the
+    // build tree (same as scripts/build/findUpDir.js)
+
+    export function findUpFile(name: string) {
+        let dir = __dirname;
+        while (true) {
+            const fullPath = join(dir, name);
+            if (existsSync(fullPath)) return fullPath;
+            const up = resolve(dir, "..");
+            if (up === dir) return name; // it'll fail anyway
+            dir = up;
+        }
+    }
+
+    export const findUpRoot: { (): string; cached?: string; } = () =>
+        findUpRoot.cached ||= dirname(findUpFile("Gulpfile.js"));
+}

src/harness/harnessIO.ts

@@ -303,21 +303,21 @@ namespace Harness {
 
         // Additional options not already in ts.optionDeclarations
         const harnessOptionDeclarations: ts.CommandLineOption[] = [
-            { name: "allowNonTsExtensions", type: "boolean" },
-            { name: "useCaseSensitiveFileNames", type: "boolean" },
+            { name: "allowNonTsExtensions", type: "boolean", defaultValueDescription: "false" },
+            { name: "useCaseSensitiveFileNames", type: "boolean", defaultValueDescription: "false" },
             { name: "baselineFile", type: "string" },
             { name: "includeBuiltFile", type: "string" },
             { name: "fileName", type: "string" },
             { name: "libFiles", type: "string" },
-            { name: "noErrorTruncation", type: "boolean" },
-            { name: "suppressOutputPathCheck", type: "boolean" },
-            { name: "noImplicitReferences", type: "boolean" },
+            { name: "noErrorTruncation", type: "boolean", defaultValueDescription: "false" },
+            { name: "suppressOutputPathCheck", type: "boolean", defaultValueDescription: "false" },
+            { name: "noImplicitReferences", type: "boolean", defaultValueDescription: "false" },
             { name: "currentDirectory", type: "string" },
             { name: "symlink", type: "string" },
             { name: "link", type: "string" },
-            { name: "noTypesAndSymbols", type: "boolean" },
+            { name: "noTypesAndSymbols", type: "boolean", defaultValueDescription: "false" },
             // Emitted js baseline will print full paths for every output file
-            { name: "fullEmitPaths", type: "boolean" }
+            { name: "fullEmitPaths", type: "boolean", defaultValueDescription: "false" }
         ];
 
         let optionsIndex: ts.ESMap<string, ts.CommandLineOption>;

src/lib/es5.d.ts

@@ -196,13 +196,13 @@ interface ObjectConstructor {
 
     /**
      * Prevents the modification of existing property attributes and values, and prevents the addition of new properties.
-     * @param o Object on which to lock the attributes.
+     * @param a Object on which to lock the attributes.
      */
     freeze<T>(a: T[]): readonly T[];
 
     /**
      * Prevents the modification of existing property attributes and values, and prevents the addition of new properties.
-     * @param o Object on which to lock the attributes.
+     * @param f Object on which to lock the attributes.
      */
     freeze<T extends Function>(f: T): T;
 

src/loc/lcl/chs/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -468,6 +468,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[映射的类型可能不声明属性或方法。]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4065,11 +4074,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[转换为 ES6 模块]]></Val>
+            <Val><![CDATA[转换为 ES 模块]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6294,11 +6303,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[文件是 CommonJS 模块；它可能会转换为 ES6 模块。]]></Val>
+            <Val><![CDATA[文件是 CommonJS 模块; 它可能会转换为 ES 模块。]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15258,6 +15267,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[不允许将 '{0}' 作为参数名。]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/cht/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -468,6 +468,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[對應型別不能宣告屬性或方法。]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4065,11 +4074,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[轉換為 ES6 模組]]></Val>
+            <Val><![CDATA[轉換為 ES 模組]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6294,11 +6303,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[檔案為 CommonJS 模組; 其可轉換為 ES6 模組。]]></Val>
+            <Val><![CDATA[檔案為 CommonJS 模組; 其可轉換為 ES 模組。]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15258,6 +15267,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[不允許 '{0}' 做為參數名稱。]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/csy/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -477,6 +477,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Mapovaný typ nemůže deklarovat vlastnosti nebo metody.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4074,11 +4083,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Převést na modul ES6]]></Val>
+            <Val><![CDATA[Převést na modul ES]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6303,11 +6312,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Soubor je modul CommonJS; může se převést na modul ES6.]]></Val>
+            <Val><![CDATA[Soubor je modul CommonJS; může být převeden na modul ES.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15267,6 +15276,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[{0} není povolen jako název parametru.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/deu/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -468,6 +468,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Ein zugeordneter Typ darf keine Eigenschaften oder Methoden deklarieren.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4062,11 +4071,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[In ES6-Modul konvertieren]]></Val>
+            <Val><![CDATA[In ES-Modul konvertieren]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6291,11 +6300,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Die Datei ist ein CommonJS-Modul, sie kann in ein ES6-Modul konvertiert werden.]]></Val>
+            <Val><![CDATA[Die Datei ist ein CommonJS-Modul und kann möglicherweise in ein ES-Modul konvertiert werden.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15252,6 +15261,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA["{0}" ist als Parametername nicht zulässig.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/esn/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -477,6 +477,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Un tipo asignado no puede declarar propiedades ni métodos.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4077,11 +4086,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Convertir en módulo ES6]]></Val>
+            <Val><![CDATA[Convertir en módulo ES]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6306,11 +6315,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[El archivo es un módulo CommonJS; se puede convertir a un módulo ES6.]]></Val>
+            <Val><![CDATA[El archivo es un módulo CommonJS; se puede convertir en un módulo ES.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15270,6 +15279,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[No se permite “{0}” como nombre de parámetro.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/fra/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -477,6 +477,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Un type mappé ne peut pas déclarer de propriétés ou de méthodes.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4077,11 +4086,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Convertir en module ES6]]></Val>
+            <Val><![CDATA[Convertir en module ES]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6306,11 +6315,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Le fichier est un module CommonJS ; il peut être converti en module ES6.]]></Val>
+            <Val><![CDATA[Le fichier est un module CommonJS ; il peut être converti en module ES.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15270,6 +15279,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA['{0}' n'est pas autorisé comme nom de paramètre.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/ita/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -468,6 +468,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Un tipo di cui è stato eseguito il mapping non può dichiarare proprietà o metodi.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4065,11 +4074,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Convertire nel modulo ES6]]></Val>
+            <Val><![CDATA[Converti nel modulo ES6]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6294,11 +6303,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Il file è un modulo CommonJS; può essere convertito in un modulo ES6.]]></Val>
+            <Val><![CDATA[Il file è un modulo CommonJS e può essere convertito in un modulo ES6.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15258,6 +15267,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA['{0}' non è un nome di parametro consentito.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/jpn/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -468,6 +468,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[マップされた型では、プロパティまたはメソッドを宣言しない場合があります。]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4065,11 +4074,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[ES6 モジュールに変換します]]></Val>
+            <Val><![CDATA[ES モジュールに変換する]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6294,11 +6303,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[ファイルは CommonJS モジュールです。ES6 モジュールに変換される可能性があります。]]></Val>
+            <Val><![CDATA[ファイルは CommonJS モジュールです。ES モジュールに変換される可能性があります。]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15258,6 +15267,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA['{0}' はパラメーター名として使用できません。]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/kor/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -468,6 +468,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[매핑된 형식은 속성 또는 메서드를 선언할 수 없습니다.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4065,11 +4074,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[ES6 모듈로 변환]]></Val>
+            <Val><![CDATA[ES 모듈로 변환]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6294,11 +6303,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[파일이 CommonJS 모듈입니다. ES6 모듈로 변환될 수 있습니다.]]></Val>
+            <Val><![CDATA[파일이 CommonJS 모듈입니다. ES 모듈로 변환될 수 있습니다.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15258,6 +15267,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA['{0}'은(는) 매개 변수 이름으로 사용할 수 없습니다.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/plk/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -461,6 +461,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Zmapowany typ nie może deklarować właściwości ani metod.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4055,11 +4064,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Konwertuj na moduł ES6]]></Val>
+            <Val><![CDATA[Konwertuj na moduł ES]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6284,11 +6293,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Plik jest modułem CommonJS. Może zostać przekonwertowany na moduł ES6.]]></Val>
+            <Val><![CDATA[Plik jest modułem CommonJS; może zostać przekonwertowany na moduł ES.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15245,6 +15254,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[„{0}” jest niedozwolone jako nazwa parametru.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/ptb/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -461,6 +461,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Um tipo mapeado não pode declarar propriedades ou métodos.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4058,11 +4067,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Converter em módulo ES6]]></Val>
+            <Val><![CDATA[Converter em módulo ES]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6287,11 +6296,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[O arquivo é um módulo CommonJS; ele pode ser convertido em um módulo ES6.]]></Val>
+            <Val><![CDATA[O arquivo é um módulo CommonJS; ele pode ser convertido em um módulo ES.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15248,6 +15257,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA['{0}' não é permitido como um nome de parâmetro.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/rus/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -467,6 +467,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Сопоставленный тип не может объявлять свойства и методы.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4064,11 +4073,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Преобразовать в модуль ES6]]></Val>
+            <Val><![CDATA[Преобразовать в модуль ES]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6293,11 +6302,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Файл является модулем CommonJS; его можно преобразовать в модуль ES6.]]></Val>
+            <Val><![CDATA[Файл является модулем CommonJS. Его можно преобразовать в модуль ES.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15257,6 +15266,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA["{0}" не является допустимым именем параметра.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loc/lcl/trk/diagnosticMessages/diagnosticMessages.generated.json.lcl

@@ -461,6 +461,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";A_mapped_type_may_not_declare_properties_or_methods_7061" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA[A mapped type may not declare properties or methods.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA[Eşlenmiş bir tür özellik veya metot bildiremez.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_memb_2651" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA[A member initializer in a enum declaration cannot reference members declared after it, including members defined in other enums.]]></Val>
@@ -4058,11 +4067,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";Convert_to_ES6_module_95017" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";Convert_to_ES_module_95017" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[Convert to ES6 module]]></Val>
+          <Val><![CDATA[Convert to ES module]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[ES6 modülüne dönüştür]]></Val>
+            <Val><![CDATA[ES modülüne dönüştür]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -6287,11 +6296,11 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
-      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module_80001" ItemType="0" PsrId="306" Leaf="true">
+      <Item ItemId=";File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module_80001" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
-          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES6 module.]]></Val>
+          <Val><![CDATA[File is a CommonJS module; it may be converted to an ES module.]]></Val>
           <Tgt Cat="Text" Stat="Loc" Orig="New">
-            <Val><![CDATA[Bir CommonJS modülü olan dosya, ES6 modülüne dönüştürülebilir.]]></Val>
+            <Val><![CDATA[Bir CommonJS modülü olan dosya bir ES modülüne dönüştürülebilir.]]></Val>
           </Tgt>
         </Str>
         <Disp Icon="Str" />
@@ -15251,6 +15260,15 @@
         </Str>
         <Disp Icon="Str" />
       </Item>
+      <Item ItemId=";_0_is_not_allowed_as_a_parameter_name_1390" ItemType="0" PsrId="306" Leaf="true">
+        <Str Cat="Text">
+          <Val><![CDATA['{0}' is not allowed as a parameter name.]]></Val>
+          <Tgt Cat="Text" Stat="Loc" Orig="New">
+            <Val><![CDATA['{0}' öğesine parametre adı olarak izin verilmiyor.]]></Val>
+          </Tgt>
+        </Str>
+        <Disp Icon="Str" />
+      </Item>
       <Item ItemId=";_0_is_not_allowed_as_a_variable_declaration_name_1389" ItemType="0" PsrId="306" Leaf="true">
         <Str Cat="Text">
           <Val><![CDATA['{0}' is not allowed as a variable declaration name.]]></Val>

src/loggedIO/loggedIO.ts

@@ -1,4 +1,4 @@
-namespace Playback {
+namespace Playback { // eslint-disable-line one-namespace-per-file
     interface FileInformation {
         contents?: string;
         contentsPath?: string;
@@ -445,3 +445,7 @@ namespace Playback {
         return wrapper;
     }
 }
+
+// empty modules for the module migration script
+namespace ts.server { } // eslint-disable-line one-namespace-per-file
+namespace Harness { } // eslint-disable-line one-namespace-per-file

src/services/codefixes/convertLiteralTypeToMappedType.ts

@@ -47,7 +47,12 @@ namespace ts.codefix {
     }
 
     function doChange(changes: textChanges.ChangeTracker, sourceFile: SourceFile, { container, typeNode, constraint, name }: Info): void {
-        changes.replaceNode(sourceFile, container, factory.createMappedTypeNode(/*readonlyToken*/ undefined,
-            factory.createTypeParameterDeclaration(name, factory.createTypeReferenceNode(constraint)), /*nameType*/ undefined, /*questionToken*/ undefined, typeNode));
+        changes.replaceNode(sourceFile, container, factory.createMappedTypeNode(
+            /*readonlyToken*/ undefined,
+            factory.createTypeParameterDeclaration(name, factory.createTypeReferenceNode(constraint)),
+            /*nameType*/ undefined,
+            /*questionToken*/ undefined,
+            typeNode,
+            /*members*/ undefined));
     }
 }

src/services/codefixes/convertToEsModule.ts

@@ -1,11 +1,11 @@
 /* @internal */
 namespace ts.codefix {
     registerCodeFix({
-        errorCodes: [Diagnostics.File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module.code],
+        errorCodes: [Diagnostics.File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module.code],
         getCodeActions(context) {
             const { sourceFile, program, preferences } = context;
             const changes = textChanges.ChangeTracker.with(context, changes => {
-                const moduleExportsChangedToDefault = convertFileToEs6Module(sourceFile, program.getTypeChecker(), changes, getEmitScriptTarget(program.getCompilerOptions()), getQuotePreference(sourceFile, preferences));
+                const moduleExportsChangedToDefault = convertFileToEsModule(sourceFile, program.getTypeChecker(), changes, getEmitScriptTarget(program.getCompilerOptions()), getQuotePreference(sourceFile, preferences));
                 if (moduleExportsChangedToDefault) {
                     for (const importingFile of program.getSourceFiles()) {
                         fixImportOfModuleExports(importingFile, sourceFile, changes, getQuotePreference(importingFile, preferences));
@@ -13,7 +13,7 @@ namespace ts.codefix {
                 }
             });
             // No support for fix-all since this applies to the whole file at once anyway.
-            return [createCodeFixActionWithoutFixAll("convertToEs6Module", changes, Diagnostics.Convert_to_ES6_module)];
+            return [createCodeFixActionWithoutFixAll("convertToEsModule", changes, Diagnostics.Convert_to_ES_module)];
         },
     });
 
@@ -39,7 +39,7 @@ namespace ts.codefix {
     }
 
     /** @returns Whether we converted a `module.exports =` to a default export. */
-    function convertFileToEs6Module(sourceFile: SourceFile, checker: TypeChecker, changes: textChanges.ChangeTracker, target: ScriptTarget, quotePreference: QuotePreference): ModuleExportsChanged {
+    function convertFileToEsModule(sourceFile: SourceFile, checker: TypeChecker, changes: textChanges.ChangeTracker, target: ScriptTarget, quotePreference: QuotePreference): ModuleExportsChanged {
         const identifiers: Identifiers = { original: collectFreeIdentifiers(sourceFile), additional: new Set() };
         const exports = collectExportRenames(sourceFile, checker, identifiers);
         convertExportsAccesses(sourceFile, exports, changes);
@@ -210,7 +210,7 @@ namespace ts.codefix {
                 // `const a = require("b").c` --> `import { c as a } from "./b";
                 return convertedImports([makeSingleImport(name.text, propertyName, moduleSpecifier, quotePreference)]);
             default:
-                return Debug.assertNever(name, `Convert to ES6 module got invalid syntax form ${(name as BindingName).kind}`);
+                return Debug.assertNever(name, `Convert to ES module got invalid syntax form ${(name as BindingName).kind}`);
         }
     }
 
@@ -430,7 +430,7 @@ namespace ts.codefix {
             case SyntaxKind.Identifier:
                 return convertSingleIdentifierImport(name, moduleSpecifier, checker, identifiers, quotePreference);
             default:
-                return Debug.assertNever(name, `Convert to ES6 module got invalid name kind ${(name as BindingName).kind}`);
+                return Debug.assertNever(name, `Convert to ES module got invalid name kind ${(name as BindingName).kind}`);
         }
     }
 

src/services/codefixes/convertToMappedObjectType.ts

@@ -46,7 +46,8 @@ namespace ts.codefix {
             mappedTypeParameter,
             /*nameType*/ undefined,
             indexSignature.questionToken,
-            indexSignature.type);
+            indexSignature.type,
+            /*members*/ undefined);
         const intersectionType = factory.createIntersectionTypeNode([
             ...getAllSuperTypeNodes(container),
             mappedIntersectionType,

src/services/codefixes/fixAwaitInSyncFunction.ts

@@ -53,7 +53,8 @@ namespace ts.codefix {
                 insertBefore = findChildOfKind(containingFunction, SyntaxKind.FunctionKeyword, sourceFile);
                 break;
             case SyntaxKind.ArrowFunction:
-                insertBefore = findChildOfKind(containingFunction, SyntaxKind.OpenParenToken, sourceFile) || first(containingFunction.parameters);
+                const kind = containingFunction.typeParameters ? SyntaxKind.LessThanToken : SyntaxKind.OpenParenToken;
+                insertBefore = findChildOfKind(containingFunction, kind, sourceFile) || first(containingFunction.parameters);
                 break;
             default:
                 return;

src/services/codefixes/importFixes.ts

@@ -268,7 +268,7 @@ namespace ts.codefix {
     }
 
     export function getImportCompletionAction(
-        exportedSymbol: Symbol,
+        targetSymbol: Symbol,
         moduleSymbol: Symbol,
         sourceFile: SourceFile,
         symbolName: string,
@@ -280,8 +280,8 @@ namespace ts.codefix {
     ): { readonly moduleSpecifier: string, readonly codeAction: CodeAction } {
         const compilerOptions = program.getCompilerOptions();
         const exportInfos = pathIsBareSpecifier(stripQuotes(moduleSymbol.name))
-            ? [getSymbolExportInfoForSymbol(exportedSymbol, moduleSymbol, program, host)]
-            : getAllReExportingModules(sourceFile, exportedSymbol, moduleSymbol, symbolName, host, program, preferences, /*useAutoImportProvider*/ true);
+            ? [getSymbolExportInfoForSymbol(targetSymbol, moduleSymbol, program, host)]
+            : getAllReExportingModules(sourceFile, targetSymbol, moduleSymbol, symbolName, host, program, preferences, /*useAutoImportProvider*/ true);
         const useRequire = shouldUseRequire(sourceFile, program);
         const isValidTypeOnlyUseSite = isValidTypeOnlyAliasUseSite(getTokenAtPosition(sourceFile, position));
         const fix = Debug.checkDefined(getImportFixForSymbol(sourceFile, exportInfos, moduleSymbol, symbolName, program, position, isValidTypeOnlyUseSite, useRequire, host, preferences));
@@ -326,7 +326,7 @@ namespace ts.codefix {
         }
     }
 
-    function getAllReExportingModules(importingFile: SourceFile, exportedSymbol: Symbol, exportingModuleSymbol: Symbol, symbolName: string, host: LanguageServiceHost, program: Program, preferences: UserPreferences, useAutoImportProvider: boolean): readonly SymbolExportInfo[] {
+    function getAllReExportingModules(importingFile: SourceFile, targetSymbol: Symbol, exportingModuleSymbol: Symbol, symbolName: string, host: LanguageServiceHost, program: Program, preferences: UserPreferences, useAutoImportProvider: boolean): readonly SymbolExportInfo[] {
         const result: SymbolExportInfo[] = [];
         const compilerOptions = program.getCompilerOptions();
         const getModuleSpecifierResolutionHost = memoizeOne((isFromPackageJson: boolean) => {
@@ -341,12 +341,12 @@ namespace ts.codefix {
             }
 
             const defaultInfo = getDefaultLikeExportInfo(moduleSymbol, checker, compilerOptions);
-            if (defaultInfo && (defaultInfo.name === symbolName || moduleSymbolToValidIdentifier(moduleSymbol, getEmitScriptTarget(compilerOptions)) === symbolName) && skipAlias(defaultInfo.symbol, checker) === exportedSymbol && isImportable(program, moduleFile, isFromPackageJson)) {
+            if (defaultInfo && (defaultInfo.name === symbolName || moduleSymbolToValidIdentifier(moduleSymbol, getEmitScriptTarget(compilerOptions)) === symbolName) && skipAlias(defaultInfo.symbol, checker) === targetSymbol && isImportable(program, moduleFile, isFromPackageJson)) {
                 result.push({ symbol: defaultInfo.symbol, moduleSymbol, moduleFileName: moduleFile?.fileName, exportKind: defaultInfo.exportKind, targetFlags: skipAlias(defaultInfo.symbol, checker).flags, isFromPackageJson });
             }
 
             for (const exported of checker.getExportsAndPropertiesOfModule(moduleSymbol)) {
-                if (exported.name === symbolName && skipAlias(exported, checker) === exportedSymbol && isImportable(program, moduleFile, isFromPackageJson)) {
+                if (exported.name === symbolName && checker.getMergedSymbol(skipAlias(exported, checker)) === targetSymbol && isImportable(program, moduleFile, isFromPackageJson)) {
                     result.push({ symbol: exported, moduleSymbol, moduleFileName: moduleFile?.fileName, exportKind: ExportKind.Named, targetFlags: skipAlias(exported, checker).flags, isFromPackageJson });
                 }
             }
@@ -663,13 +663,15 @@ namespace ts.codefix {
         }
         const { allowsImportingSpecifier } = createPackageJsonImportFilter(sourceFile, preferences, host);
         return fixes.reduce((best, fix) =>
+            // Takes true branch of conditional if `fix` is better than `best`
             compareModuleSpecifiers(fix, best, sourceFile, program, allowsImportingSpecifier) === Comparison.LessThan ? fix : best
         );
     }
 
+    /** @returns `Comparison.LessThan` if `a` is better than `b`. */
     function compareModuleSpecifiers(a: ImportFix, b: ImportFix, importingFile: SourceFile, program: Program, allowsImportingSpecifier: (specifier: string) => boolean): Comparison {
         if (a.kind !== ImportFixKind.UseNamespace && b.kind !== ImportFixKind.UseNamespace) {
-            return compareBooleans(allowsImportingSpecifier(a.moduleSpecifier), allowsImportingSpecifier(b.moduleSpecifier))
+            return compareBooleans(allowsImportingSpecifier(b.moduleSpecifier), allowsImportingSpecifier(a.moduleSpecifier))
                 || compareNodeCoreModuleSpecifiers(a.moduleSpecifier, b.moduleSpecifier, importingFile, program)
                 || compareNumberOfDirectorySeparators(a.moduleSpecifier, b.moduleSpecifier);
         }
@@ -766,9 +768,13 @@ namespace ts.codefix {
         return { fixes, symbolName };
     }
 
+    function jsxModeNeedsExplicitImport(jsx: JsxEmit | undefined) {
+        return jsx === JsxEmit.React || jsx === JsxEmit.ReactNative;
+    }
+
     function getSymbolName(sourceFile: SourceFile, checker: TypeChecker, symbolToken: Identifier, compilerOptions: CompilerOptions): string {
         const parent = symbolToken.parent;
-        if ((isJsxOpeningLikeElement(parent) || isJsxClosingElement(parent)) && parent.tagName === symbolToken && compilerOptions.jsx !== JsxEmit.ReactJSX && compilerOptions.jsx !== JsxEmit.ReactJSXDev) {
+        if ((isJsxOpeningLikeElement(parent) || isJsxClosingElement(parent)) && parent.tagName === symbolToken && jsxModeNeedsExplicitImport(compilerOptions.jsx)) {
             const jsxNamespace = checker.getJsxNamespace(sourceFile);
             if (isIntrinsicJsxName(symbolToken.text) || !checker.resolveName(jsxNamespace, parent, SymbolFlags.Value, /*excludeGlobals*/ true)) {
                 return jsxNamespace;

src/services/completions.ts

@@ -1183,9 +1183,9 @@ namespace ts.Completions {
 
         const checker = origin.isFromPackageJson ? host.getPackageJsonAutoImportProvider!()!.getTypeChecker() : program.getTypeChecker();
         const { moduleSymbol } = origin;
-        const exportedSymbol = checker.getMergedSymbol(skipAlias(symbol.exportSymbol || symbol, checker));
+        const targetSymbol = checker.getMergedSymbol(skipAlias(symbol.exportSymbol || symbol, checker));
         const { moduleSpecifier, codeAction } = codefix.getImportCompletionAction(
-            exportedSymbol,
+            targetSymbol,
             moduleSymbol,
             sourceFile,
             getNameForExportedSymbol(symbol, getEmitScriptTarget(compilerOptions)),
@@ -1993,10 +1993,10 @@ namespace ts.Completions {
             if (isNonContextualObjectLiteral) return false;
             // If not already a module, must have modules enabled.
             if (!preferences.includeCompletionsForModuleExports) return false;
-            // If already using ES6 modules, OK to continue using them.
+            // If already using ES modules, OK to continue using them.
             if (sourceFile.externalModuleIndicator || sourceFile.commonJsModuleIndicator) return true;
             // If module transpilation is enabled or we're targeting es6 or above, or not emitting, OK.
-            if (compilerOptionsIndicateEs6Modules(program.getCompilerOptions())) return true;
+            if (compilerOptionsIndicateEsModules(program.getCompilerOptions())) return true;
             // If some file is using ES6 modules, assume that it's OK to add more.
             return programContainsModules(program);
         }
@@ -2209,8 +2209,9 @@ namespace ts.Completions {
         function isNewIdentifierDefinitionLocation(): boolean {
             if (contextToken) {
                 const containingNodeKind = contextToken.parent.kind;
+                const tokenKind = keywordForNode(contextToken);
                 // Previous token may have been a keyword that was converted to an identifier.
-                switch (keywordForNode(contextToken)) {
+                switch (tokenKind) {
                     case SyntaxKind.CommaToken:
                         return containingNodeKind === SyntaxKind.CallExpression               // func( a, |
                             || containingNodeKind === SyntaxKind.Constructor                  // constructor( a, |   /* public, protected, private keywords are allowed here, so show completion */
@@ -2254,10 +2255,16 @@ namespace ts.Completions {
                     case SyntaxKind.TemplateMiddle:
                         return containingNodeKind === SyntaxKind.TemplateSpan;                // `aa ${10} dd ${|
 
-                    case SyntaxKind.PublicKeyword:
-                    case SyntaxKind.PrivateKeyword:
-                    case SyntaxKind.ProtectedKeyword:
-                        return containingNodeKind === SyntaxKind.PropertyDeclaration;         // class A{ public |
+                    case SyntaxKind.AsyncKeyword:
+                        return containingNodeKind === SyntaxKind.MethodDeclaration            // const obj = { async c|()
+                            || containingNodeKind === SyntaxKind.ShorthandPropertyAssignment; // const obj = { async c|
+
+                    case SyntaxKind.AsteriskToken:
+                        return containingNodeKind === SyntaxKind.MethodDeclaration;           // const obj = { * c|
+                }
+
+                if (isClassMemberCompletionKeyword(tokenKind)) {
+                    return true;
                 }
             }
 

src/services/exportInfoMap.ts

@@ -79,10 +79,14 @@ namespace ts {
                 }
                 const isDefault = exportKind === ExportKind.Default;
                 const namedSymbol = isDefault && getLocalSymbolForExportDefault(symbol) || symbol;
-                // A re-export merged with an export from a module augmentation can result in `symbol`
-                // being an external module symbol; the name it is re-exported by will be `symbolTableKey`
-                // (which comes from the keys of `moduleSymbol.exports`.)
-                const importedName = isExternalModuleSymbol(namedSymbol)
+                // 1. A named export must be imported by its key in `moduleSymbol.exports` or `moduleSymbol.members`.
+                // 2. A re-export merged with an export from a module augmentation can result in `symbol`
+                //    being an external module symbol; the name it is re-exported by will be `symbolTableKey`
+                //    (which comes from the keys of `moduleSymbol.exports`.)
+                // 3. Otherwise, we have a default/namespace import that can be imported by any name, and
+                //    `symbolTableKey` will be something undesirable like `export=` or `default`, so we try to
+                //    get a better name.
+                const importedName = exportKind === ExportKind.Named || isExternalModuleSymbol(namedSymbol)
                     ? unescapeLeadingUnderscores(symbolTableKey)
                     : getNameForExportedSymbol(namedSymbol, scriptTarget);
                 const moduleName = stripQuotes(moduleSymbol.name);
@@ -321,7 +325,7 @@ namespace ts {
         let moduleCount = 0;
         forEachExternalModuleToImportFrom(program, host, /*useAutoImportProvider*/ true, (moduleSymbol, moduleFile, program, isFromPackageJson) => {
             if (++moduleCount % 100 === 0) cancellationToken?.throwIfCancellationRequested();
-            const seenExports = new Map<Symbol, true>();
+            const seenExports = new Map<__String, true>();
             const checker = program.getTypeChecker();
             const defaultInfo = getDefaultLikeExportInfo(moduleSymbol, checker, compilerOptions);
             // Note: I think we shouldn't actually see resolved module symbols here, but weird merges
@@ -339,7 +343,7 @@ namespace ts {
                     checker);
             }
             checker.forEachExportAndPropertyOfModule(moduleSymbol, (exported, key) => {
-                if (exported !== defaultInfo?.symbol && isImportableSymbol(exported, checker) && addToSeen(seenExports, exported)) {
+                if (exported !== defaultInfo?.symbol && isImportableSymbol(exported, checker) && addToSeen(seenExports, key)) {
                     cache.add(
                         importingFile.path,
                         exported,

src/services/refactors/moveToNewFile.ts

@@ -138,9 +138,9 @@ namespace ts.refactor {
             return [...prologueDirectives, ...toMove.all];
         }
 
-        const useEs6ModuleSyntax = !!oldFile.externalModuleIndicator;
+        const useEsModuleSyntax = !!oldFile.externalModuleIndicator;
         const quotePreference = getQuotePreference(oldFile, preferences);
-        const importsFromNewFile = createOldFileImportsFromNewFile(usage.oldFileImportsFromNewFile, newModuleName, useEs6ModuleSyntax, quotePreference);
+        const importsFromNewFile = createOldFileImportsFromNewFile(usage.oldFileImportsFromNewFile, newModuleName, useEsModuleSyntax, quotePreference);
         if (importsFromNewFile) {
             insertImports(changes, oldFile, importsFromNewFile, /*blankLineBetween*/ true);
         }
@@ -149,8 +149,8 @@ namespace ts.refactor {
         deleteMovedStatements(oldFile, toMove.ranges, changes);
         updateImportsInOtherFiles(changes, program, oldFile, usage.movedSymbols, newModuleName);
 
-        const imports = getNewFileImportsAndAddExportInOldFile(oldFile, usage.oldImportsNeededByNewFile, usage.newFileImportsFromOldFile, changes, checker, useEs6ModuleSyntax, quotePreference);
-        const body = addExports(oldFile, toMove.all, usage.oldFileImportsFromNewFile, useEs6ModuleSyntax);
+        const imports = getNewFileImportsAndAddExportInOldFile(oldFile, usage.oldImportsNeededByNewFile, usage.newFileImportsFromOldFile, changes, checker, useEsModuleSyntax, quotePreference);
+        const body = addExports(oldFile, toMove.all, usage.oldFileImportsFromNewFile, useEsModuleSyntax);
         if (imports.length && body.length) {
             return [
                 ...prologueDirectives,
@@ -429,7 +429,7 @@ namespace ts.refactor {
         newFileImportsFromOldFile: ReadonlySymbolSet,
         changes: textChanges.ChangeTracker,
         checker: TypeChecker,
-        useEs6ModuleSyntax: boolean,
+        useEsModuleSyntax: boolean,
         quotePreference: QuotePreference,
     ): readonly SupportedImportStatement[] {
         const copiedOldImports: SupportedImportStatement[] = [];
@@ -454,7 +454,7 @@ namespace ts.refactor {
 
                 const top = getTopLevelDeclarationStatement(decl);
                 if (markSeenTop(top)) {
-                    addExportToChanges(oldFile, top, name, changes, useEs6ModuleSyntax);
+                    addExportToChanges(oldFile, top, name, changes, useEsModuleSyntax);
                 }
                 if (hasSyntacticModifier(decl, ModifierFlags.Default)) {
                     oldFileDefault = name;
@@ -465,7 +465,7 @@ namespace ts.refactor {
             }
         });
 
-        append(copiedOldImports, makeImportOrRequire(oldFileDefault, oldFileNamedImports, removeFileExtension(getBaseFileName(oldFile.fileName)), useEs6ModuleSyntax, quotePreference));
+        append(copiedOldImports, makeImportOrRequire(oldFileDefault, oldFileNamedImports, removeFileExtension(getBaseFileName(oldFile.fileName)), useEsModuleSyntax, quotePreference));
         return copiedOldImports;
     }
 

src/services/suggestionDiagnostics.ts

@@ -6,11 +6,13 @@ namespace ts {
         program.getSemanticDiagnostics(sourceFile, cancellationToken);
         const diags: DiagnosticWithLocation[] = [];
         const checker = program.getTypeChecker();
+        const isCommonJSFile = sourceFile.impliedNodeFormat === ModuleKind.CommonJS || fileExtensionIsOneOf(sourceFile.fileName, [Extension.Cts, Extension.Cjs]) ;
 
-        if (sourceFile.commonJsModuleIndicator &&
-            (programContainsEs6Modules(program) || compilerOptionsIndicateEs6Modules(program.getCompilerOptions())) &&
+        if (!isCommonJSFile &&
+            sourceFile.commonJsModuleIndicator &&
+            (programContainsEsModules(program) || compilerOptionsIndicateEsModules(program.getCompilerOptions())) &&
             containsTopLevelCommonjs(sourceFile)) {
-            diags.push(createDiagnosticForNode(getErrorNodeFromCommonJsIndicator(sourceFile.commonJsModuleIndicator), Diagnostics.File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module));
+            diags.push(createDiagnosticForNode(getErrorNodeFromCommonJsIndicator(sourceFile.commonJsModuleIndicator), Diagnostics.File_is_a_CommonJS_module_it_may_be_converted_to_an_ES_module));
         }
 
         const isJsFile = isSourceFileJS(sourceFile);
@@ -64,7 +66,7 @@ namespace ts {
         }
     }
 
-    // convertToEs6Module only works on top-level, so don't trigger it if commonjs code only appears in nested scopes.
+    // convertToEsModule only works on top-level, so don't trigger it if commonjs code only appears in nested scopes.
     function containsTopLevelCommonjs(sourceFile: SourceFile): boolean {
         return sourceFile.statements.some(statement => {
             switch (statement.kind) {

src/services/tsconfig.json

@@ -61,7 +61,7 @@
         "codefixes/annotateWithTypeFromJSDoc.ts",
         "codefixes/convertFunctionToEs6Class.ts",
         "codefixes/convertToAsyncFunction.ts",
-        "codefixes/convertToEs6Module.ts",
+        "codefixes/convertToEsModule.ts",
         "codefixes/correctQualifiedNameToIndexedAccessType.ts",
         "codefixes/convertToTypeOnlyExport.ts",
         "codefixes/convertToTypeOnlyImport.ts",

src/services/utilities.ts

@@ -1897,10 +1897,10 @@ namespace ts {
     export function programContainsModules(program: Program): boolean {
         return program.getSourceFiles().some(s => !s.isDeclarationFile && !program.isSourceFileFromExternalLibrary(s) && !!(s.externalModuleIndicator || s.commonJsModuleIndicator));
     }
-    export function programContainsEs6Modules(program: Program): boolean {
+    export function programContainsEsModules(program: Program): boolean {
         return program.getSourceFiles().some(s => !s.isDeclarationFile && !program.isSourceFileFromExternalLibrary(s) && !!s.externalModuleIndicator);
     }
-    export function compilerOptionsIndicateEs6Modules(compilerOptions: CompilerOptions): boolean {
+    export function compilerOptionsIndicateEsModules(compilerOptions: CompilerOptions): boolean {
         return !!compilerOptions.module || getEmitScriptTarget(compilerOptions) >= ScriptTarget.ES2015 || !!compilerOptions.noEmit;
     }
 
@@ -2290,9 +2290,9 @@ namespace ts {
         return displayPart(text, SymbolDisplayPartKind.linkText);
     }
 
-    export function linkNamePart(name: EntityName | JSDocMemberName, target: Declaration): JSDocLinkDisplayPart {
+    export function linkNamePart(text: string, target: Declaration): JSDocLinkDisplayPart {
         return {
-            text: getTextOfNode(name),
+            text,
             kind: SymbolDisplayPartKind[SymbolDisplayPartKind.linkName],
             target: {
                 fileName: getSourceFileOfNode(target).fileName,
@@ -2315,19 +2315,36 @@ namespace ts {
         }
         else {
             const symbol = checker?.getSymbolAtLocation(link.name);
+            const suffix = findLinkNameEnd(link.text);
+            const name = getTextOfNode(link.name) + link.text.slice(0, suffix);
+            const text = link.text.slice(suffix);
             const decl = symbol?.valueDeclaration || symbol?.declarations?.[0];
             if (decl) {
-                parts.push(linkNamePart(link.name, decl));
-                if (link.text) parts.push(linkTextPart(link.text));
+                parts.push(linkNamePart(name, decl));
+                if (text) parts.push(linkTextPart(text));
             }
             else {
-                parts.push(linkTextPart(getTextOfNode(link.name) + " " + link.text));
+                parts.push(linkTextPart(name + (suffix ? "" : " ") + text));
             }
         }
         parts.push(linkPart("}"));
         return parts;
     }
 
+    function findLinkNameEnd(text: string) {
+        if (text.indexOf("()") === 0) return 2;
+        if (text[0] !== "<") return 0;
+        let brackets = 0;
+        let i = 0;
+        while (i < text.length) {
+            if (text[i] === "<") brackets++;
+            if (text[i] === ">") brackets--;
+            i++;
+            if (!brackets) return i;
+        }
+        return 0;
+    }
+
     const carriageReturnLineFeed = "\r\n";
     /**
      * The default is CRLF.

src/testRunner/tsconfig.json

@@ -100,6 +100,7 @@
         "unittests/evaluation/optionalCall.ts",
         "unittests/evaluation/objectRest.ts",
         "unittests/evaluation/superInStaticInitializer.ts",
+        "unittests/evaluation/templateLiteral.ts",
         "unittests/evaluation/updateExpressionInModule.ts",
         "unittests/services/cancellableLanguageServiceOperations.ts",
         "unittests/services/colorization.ts",
@@ -157,6 +158,7 @@
         "unittests/tsc/runWithoutArgs.ts",
         "unittests/tscWatch/consoleClearing.ts",
         "unittests/tscWatch/emit.ts",
+        "unittests/tscWatch/nodeNextWatch.ts",
         "unittests/tscWatch/emitAndErrorUpdates.ts",
         "unittests/tscWatch/forceConsistentCasingInFileNames.ts",
         "unittests/tscWatch/incremental.ts",

src/testRunner/unittests/config/commandLineParsing.ts

@@ -526,7 +526,7 @@ namespace ts {
                     nonNullValue,
                     diagnosticMessage: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_null_on_command_line,
                     workerDiagnostic: () => {
-                        const optionDeclarations = [
+                        const optionDeclarations: CommandLineOption[] = [
                             ...compilerOptionsDidYouMeanDiagnostics.optionDeclarations,
                             {
                                 name: "optionName",
@@ -534,6 +534,7 @@ namespace ts {
                                 isTSConfigOnly: true,
                                 category: Diagnostics.Backwards_Compatibility,
                                 description: Diagnostics.Enable_project_compilation,
+                                defaultValueDescription: "undefined",
                             }
                         ];
                         return {

src/testRunner/unittests/evaluation/templateLiteral.ts

@@ -0,0 +1,40 @@
+describe("unittests:: evaluation:: templateLiteral", () => {
+    it("toString() over valueOf()", () => {
+        const result = evaluator.evaluateTypeScript(`
+            class C {
+                toString() {
+                    return "toString";
+                }
+                valueOf() {
+                    return "valueOf";
+                }
+            }
+
+            export const output = \`\${new C}\`;
+        `);
+        assert.strictEqual(result.output, "toString");
+    });
+
+    it("correct evaluation order", () => {
+        const result = evaluator.evaluateTypeScript(`
+            class C {
+                counter: number;
+
+                constructor() {
+                    this.counter = 0;
+                }
+
+                get foo() {
+                    this.counter++;
+                    return {
+                        toString: () => this.counter++,
+                    };
+                }
+            }
+
+            const c = new C;
+            export const output = \`\${c.foo} \${c.foo}\`;
+        `);
+        assert.strictEqual(result.output, "1 3");
+    });
+});

src/testRunner/unittests/publicApi.ts

@@ -182,3 +182,34 @@ describe("unittests:: Public APIs:: getChild* methods on EndOfFileToken with JSD
     assert.equal(endOfFileToken.getChildCount(), 1);
     assert.notEqual(endOfFileToken.getChildAt(0), /*expected*/ undefined);
 });
+
+describe("unittests:: Public APIs:: sys", () => {
+    it("readDirectory", () => {
+        // #45990, testing passing a non-absolute path
+        // `sys.readDirectory` is just `matchFiles` plugged into the real FS
+        const read = ts.matchFiles(
+            /*path*/ "",
+            /*extensions*/ [".ts", ".tsx"],
+            /*excludes*/ ["node_modules", "dist"],
+            /*includes*/ ["**/*"],
+            /*useCaseSensitiveFileNames*/ true,
+            /*currentDirectory*/ "/",
+            /*depth*/ undefined,
+            /*getFileSystemEntries*/ path => {
+                switch (path) {
+                    case "/": return { directories: [], files: ["file.ts"] };
+                    default: return { directories: [], files: [] };
+                }
+            },
+            /*realpath*/ ts.identity,
+            /*directoryExists*/ path => {
+                switch (path) {
+                    case "/": return true;
+                    default: return false;
+                }
+            }
+        );
+
+        assert.deepEqual(read, ["/file.ts"]);
+    });
+});

src/testRunner/unittests/tscWatch/nodeNextWatch.ts

@@ -0,0 +1,58 @@
+namespace ts.tscWatch {
+    describe("unittests:: tsc-watch:: nodeNextWatch:: emit when module emit is specified as nodenext", () => {
+        verifyTscWatch({
+            scenario: "nodenext watch emit",
+            subScenario: "esm-mode file is edited",
+            commandLineArgs: ["--w", "--p", "/project/tsconfig.json"],
+            sys: () => {
+                const configFile: File = {
+                    path: "/project/tsconfig.json",
+                    content: JSON.stringify({
+                        compilerOptions: {
+                            strict: true,
+                            target: "es2020",
+                            module: "nodenext",
+                            moduleResolution: "nodenext",
+                            outDir: "../dist"
+                        }
+                    })
+                };
+                const packageFile: File = {
+                    path: "/project/package.json",
+                    content: JSON.stringify({
+                        name: "some-proj",
+                        version: "1.0.0",
+                        description: "",
+                        type: "module",
+                        main: "index.js",
+                    })
+                };
+                const file1: File = {
+                    path: "/project/src/index.ts",
+                    content: Utils.dedent`
+                        import * as Thing from "thing";
+
+                        Thing.fn();`
+                };
+                const declFile: File = {
+                    path: "/project/src/deps.d.ts",
+                    content: `declare module "thing";`
+                };
+                return createWatchedSystem([configFile, file1, declFile, packageFile, { ...libFile, path: "/a/lib/lib.es2020.full.d.ts" }]);
+            },
+            changes: [
+                {
+                    caption: "Modify typescript file",
+                    change: sys => sys.modifyFile(
+                        "/project/src/index.ts",
+                        Utils.dedent`
+                            import * as Thing from "thing";
+                            Thing.fn();`,
+                        {},
+                    ),
+                    timeouts: runQueuedTimeoutCallbacks,
+                }
+            ],
+        });
+    });
+}

src/tsserver/webServer.ts

@@ -78,7 +78,7 @@ namespace ts.server {
         };
         // Do this after sys has been set as findArguments is going to work only then
         const sys = server.createWebSystem(webHost, args, () => findArgument("--executingFilePath") || location + "");
-        ts.sys = sys;
+        setSys(sys);
         const localeStr = findArgument("--locale");
         if (localeStr) {
             validateLocaleAndSetLanguage(localeStr, sys);

tests/baselines/reference/APISample_compile.js

@@ -66,10 +66,10 @@ function compile(fileNames, options) {
             return;
         }
         var _a = diagnostic.file.getLineAndCharacterOfPosition(diagnostic.start), line = _a.line, character = _a.character;
-        console.log(diagnostic.file.fileName + " (" + (line + 1) + "," + (character + 1) + "): " + message);
+        console.log("".concat(diagnostic.file.fileName, " (").concat(line + 1, ",").concat(character + 1, "): ").concat(message));
     });
     var exitCode = emitResult.emitSkipped ? 1 : 0;
-    console.log("Process exiting with code '" + exitCode + "'.");
+    console.log("Process exiting with code '".concat(exitCode, "'."));
     process.exit(exitCode);
 }
 exports.compile = compile;

tests/baselines/reference/APISample_linter.js

@@ -114,7 +114,7 @@ function delint(sourceFile) {
     }
     function report(node, message) {
         var _a = sourceFile.getLineAndCharacterOfPosition(node.getStart()), line = _a.line, character = _a.character;
-        console.log(sourceFile.fileName + " (" + (line + 1) + "," + (character + 1) + "): " + message);
+        console.log("".concat(sourceFile.fileName, " (").concat(line + 1, ",").concat(character + 1, "): ").concat(message));
     }
 }
 exports.delint = delint;

tests/baselines/reference/APISample_parseConfig.js

@@ -56,7 +56,7 @@ function printError(error) {
     if (!error) {
         return;
     }
-    console.log((error.file && error.file.fileName) + ": " + error.messageText);
+    console.log("".concat(error.file && error.file.fileName, ": ").concat(error.messageText));
 }
 function createProgram(rootFiles, compilerOptionsJson) {
     var _a = ts.parseConfigFileTextToJson("tsconfig.json", compilerOptionsJson), config = _a.config, error = _a.error;

tests/baselines/reference/APISample_watcher.js

@@ -166,10 +166,10 @@ function watch(rootFileNames, options) {
     function emitFile(fileName) {
         var output = services.getEmitOutput(fileName);
         if (!output.emitSkipped) {
-            console.log("Emitting " + fileName);
+            console.log("Emitting ".concat(fileName));
         }
         else {
-            console.log("Emitting " + fileName + " failed");
+            console.log("Emitting ".concat(fileName, " failed"));
             logErrors(fileName);
         }
         output.outputFiles.forEach(function (o) {
@@ -184,10 +184,10 @@ function watch(rootFileNames, options) {
             var message = ts.flattenDiagnosticMessageText(diagnostic.messageText, "\n");
             if (diagnostic.file) {
                 var _a = diagnostic.file.getLineAndCharacterOfPosition(diagnostic.start), line = _a.line, character = _a.character;
-                console.log("  Error " + diagnostic.file.fileName + " (" + (line + 1) + "," + (character + 1) + "): " + message);
+                console.log("  Error ".concat(diagnostic.file.fileName, " (").concat(line + 1, ",").concat(character + 1, "): ").concat(message));
             }
             else {
-                console.log("  Error: " + message);
+                console.log("  Error: ".concat(message));
             }
         });
     }

tests/baselines/reference/TemplateExpression1.js

@@ -2,4 +2,4 @@
 var v = `foo ${ a 
 
 //// [TemplateExpression1.js]
-var v = "foo " + a;
+var v = "foo ".concat(a);

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -973,6 +973,8 @@ declare namespace ts {
         readonly nameType?: TypeNode;
         readonly questionToken?: QuestionToken | PlusToken | MinusToken;
         readonly type?: TypeNode;
+        /** Used only to produce grammar errors */
+        readonly members?: NodeArray<TypeElement>;
     }
     export interface LiteralTypeNode extends TypeNode {
         readonly kind: SyntaxKind.LiteralType;
@@ -3421,8 +3423,8 @@ declare namespace ts {
         updateTypeOperatorNode(node: TypeOperatorNode, type: TypeNode): TypeOperatorNode;
         createIndexedAccessTypeNode(objectType: TypeNode, indexType: TypeNode): IndexedAccessTypeNode;
         updateIndexedAccessTypeNode(node: IndexedAccessTypeNode, objectType: TypeNode, indexType: TypeNode): IndexedAccessTypeNode;
-        createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode;
-        updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode;
+        createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode;
+        updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode;
         createLiteralTypeNode(literal: LiteralTypeNode["literal"]): LiteralTypeNode;
         updateLiteralTypeNode(node: LiteralTypeNode, literal: LiteralTypeNode["literal"]): LiteralTypeNode;
         createTemplateLiteralType(head: TemplateHead, templateSpans: readonly TemplateLiteralTypeSpan[]): TemplateLiteralTypeNode;
@@ -10781,9 +10783,9 @@ declare namespace ts {
     /** @deprecated Use `factory.updateIndexedAccessTypeNode` or the factory supplied by your transformation context instead. */
     const updateIndexedAccessTypeNode: (node: IndexedAccessTypeNode, objectType: TypeNode, indexType: TypeNode) => IndexedAccessTypeNode;
     /** @deprecated Use `factory.createMappedTypeNode` or the factory supplied by your transformation context instead. */
-    const createMappedTypeNode: (readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined) => MappedTypeNode;
+    const createMappedTypeNode: (readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined) => MappedTypeNode;
     /** @deprecated Use `factory.updateMappedTypeNode` or the factory supplied by your transformation context instead. */
-    const updateMappedTypeNode: (node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined) => MappedTypeNode;
+    const updateMappedTypeNode: (node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined) => MappedTypeNode;
     /** @deprecated Use `factory.createLiteralTypeNode` or the factory supplied by your transformation context instead. */
     const createLiteralTypeNode: (literal: LiteralExpression | BooleanLiteral | PrefixUnaryExpression | NullLiteral) => LiteralTypeNode;
     /** @deprecated Use `factory.updateLiteralTypeNode` or the factory supplied by your transformation context instead. */

tests/baselines/reference/api/typescript.d.ts

@@ -973,6 +973,8 @@ declare namespace ts {
         readonly nameType?: TypeNode;
         readonly questionToken?: QuestionToken | PlusToken | MinusToken;
         readonly type?: TypeNode;
+        /** Used only to produce grammar errors */
+        readonly members?: NodeArray<TypeElement>;
     }
     export interface LiteralTypeNode extends TypeNode {
         readonly kind: SyntaxKind.LiteralType;
@@ -3421,8 +3423,8 @@ declare namespace ts {
         updateTypeOperatorNode(node: TypeOperatorNode, type: TypeNode): TypeOperatorNode;
         createIndexedAccessTypeNode(objectType: TypeNode, indexType: TypeNode): IndexedAccessTypeNode;
         updateIndexedAccessTypeNode(node: IndexedAccessTypeNode, objectType: TypeNode, indexType: TypeNode): IndexedAccessTypeNode;
-        createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode;
-        updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined): MappedTypeNode;
+        createMappedTypeNode(readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode;
+        updateMappedTypeNode(node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined): MappedTypeNode;
         createLiteralTypeNode(literal: LiteralTypeNode["literal"]): LiteralTypeNode;
         updateLiteralTypeNode(node: LiteralTypeNode, literal: LiteralTypeNode["literal"]): LiteralTypeNode;
         createTemplateLiteralType(head: TemplateHead, templateSpans: readonly TemplateLiteralTypeSpan[]): TemplateLiteralTypeNode;
@@ -6979,9 +6981,9 @@ declare namespace ts {
     /** @deprecated Use `factory.updateIndexedAccessTypeNode` or the factory supplied by your transformation context instead. */
     const updateIndexedAccessTypeNode: (node: IndexedAccessTypeNode, objectType: TypeNode, indexType: TypeNode) => IndexedAccessTypeNode;
     /** @deprecated Use `factory.createMappedTypeNode` or the factory supplied by your transformation context instead. */
-    const createMappedTypeNode: (readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined) => MappedTypeNode;
+    const createMappedTypeNode: (readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined) => MappedTypeNode;
     /** @deprecated Use `factory.updateMappedTypeNode` or the factory supplied by your transformation context instead. */
-    const updateMappedTypeNode: (node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined) => MappedTypeNode;
+    const updateMappedTypeNode: (node: MappedTypeNode, readonlyToken: ReadonlyKeyword | PlusToken | MinusToken | undefined, typeParameter: TypeParameterDeclaration, nameType: TypeNode | undefined, questionToken: QuestionToken | PlusToken | MinusToken | undefined, type: TypeNode | undefined, members: NodeArray<TypeElement> | undefined) => MappedTypeNode;
     /** @deprecated Use `factory.createLiteralTypeNode` or the factory supplied by your transformation context instead. */
     const createLiteralTypeNode: (literal: LiteralExpression | BooleanLiteral | PrefixUnaryExpression | NullLiteral) => LiteralTypeNode;
     /** @deprecated Use `factory.updateLiteralTypeNode` or the factory supplied by your transformation context instead. */

tests/baselines/reference/argumentsReferenceInObjectLiteral_Js.errors.txt

@@ -0,0 +1,32 @@
+/a.js(16,9): error TS18004: No value exists in scope for the shorthand property 'arguments'. Either declare one or provide an initializer.
+
+
+==== /a.js (1 errors) ====
+    const a = () => {
+        return {
+            arguments: [],
+        };
+    };
+    
+    const b = () => {
+        const c = {
+            arguments: [],
+        }
+        return c;
+    };
+    
+    const c = () => {
+        return {
+            arguments,
+            ~~~~~~~~~
+!!! error TS18004: No value exists in scope for the shorthand property 'arguments'. Either declare one or provide an initializer.
+        };
+    }
+    
+    const d = () => {
+        const arguments = undefined;
+        return {
+            arguments,
+        };
+    }
+    

tests/baselines/reference/argumentsReferenceInObjectLiteral_Js.js

@@ -0,0 +1,51 @@
+//// [a.js]
+const a = () => {
+    return {
+        arguments: [],
+    };
+};
+
+const b = () => {
+    const c = {
+        arguments: [],
+    }
+    return c;
+};
+
+const c = () => {
+    return {
+        arguments,
+    };
+}
+
+const d = () => {
+    const arguments = undefined;
+    return {
+        arguments,
+    };
+}
+
+
+//// [a.js]
+const a = () => {
+    return {
+        arguments: [],
+    };
+};
+const b = () => {
+    const c = {
+        arguments: [],
+    };
+    return c;
+};
+const c = () => {
+    return {
+        arguments,
+    };
+};
+const d = () => {
+    const arguments = undefined;
+    return {
+        arguments,
+    };
+};

tests/baselines/reference/argumentsReferenceInObjectLiteral_Js.symbols

@@ -0,0 +1,49 @@
+=== /a.js ===
+const a = () => {
+>a : Symbol(a, Decl(a.js, 0, 5))
+
+    return {
+        arguments: [],
+>arguments : Symbol(arguments, Decl(a.js, 1, 12))
+
+    };
+};
+
+const b = () => {
+>b : Symbol(b, Decl(a.js, 6, 5))
+
+    const c = {
+>c : Symbol(c, Decl(a.js, 7, 9))
+
+        arguments: [],
+>arguments : Symbol(arguments, Decl(a.js, 7, 15))
+    }
+    return c;
+>c : Symbol(c, Decl(a.js, 7, 9))
+
+};
+
+const c = () => {
+>c : Symbol(c, Decl(a.js, 13, 5))
+
+    return {
+        arguments,
+>arguments : Symbol(arguments, Decl(a.js, 14, 12))
+
+    };
+}
+
+const d = () => {
+>d : Symbol(d, Decl(a.js, 19, 5))
+
+    const arguments = undefined;
+>arguments : Symbol(arguments, Decl(a.js, 20, 9))
+>undefined : Symbol(undefined)
+
+    return {
+        arguments,
+>arguments : Symbol(arguments, Decl(a.js, 21, 12))
+
+    };
+}
+

tests/baselines/reference/argumentsReferenceInObjectLiteral_Js.types

@@ -0,0 +1,62 @@
+=== /a.js ===
+const a = () => {
+>a : () => { arguments: any[]; }
+>() => {    return {        arguments: [],    };} : () => { arguments: any[]; }
+
+    return {
+>{        arguments: [],    } : { arguments: undefined[]; }
+
+        arguments: [],
+>arguments : undefined[]
+>[] : undefined[]
+
+    };
+};
+
+const b = () => {
+>b : () => { arguments: any[]; }
+>() => {    const c = {        arguments: [],    }    return c;} : () => { arguments: any[]; }
+
+    const c = {
+>c : { arguments: any[]; }
+>{        arguments: [],    } : { arguments: undefined[]; }
+
+        arguments: [],
+>arguments : undefined[]
+>[] : undefined[]
+    }
+    return c;
+>c : { arguments: any[]; }
+
+};
+
+const c = () => {
+>c : () => { arguments: any; }
+>() => {    return {        arguments,    };} : () => { arguments: any; }
+
+    return {
+>{        arguments,    } : { arguments: any; }
+
+        arguments,
+>arguments : any
+
+    };
+}
+
+const d = () => {
+>d : () => { arguments: any; }
+>() => {    const arguments = undefined;    return {        arguments,    };} : () => { arguments: any; }
+
+    const arguments = undefined;
+>arguments : any
+>undefined : undefined
+
+    return {
+>{        arguments,    } : { arguments: any; }
+
+        arguments,
+>arguments : any
+
+    };
+}
+

tests/baselines/reference/asOperator3.js

@@ -15,11 +15,11 @@ var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cook
     if (Object.defineProperty) { Object.defineProperty(cooked, "raw", { value: raw }); } else { cooked.raw = raw; }
     return cooked;
 };
-var a = "" + (123 + 456);
-var b = "leading " + (123 + 456);
-var c = 123 + 456 + " trailing";
-var d = "Hello " + 123 + " World";
+var a = "".concat(123 + 456);
+var b = "leading ".concat(123 + 456);
+var c = "".concat(123 + 456, " trailing");
+var d = "Hello ".concat(123, " World");
 var e = "Hello";
-var f = 1 + (1 + " end of string");
+var f = 1 + "".concat(1, " end of string");
 var g = tag(__makeTemplateObject(["Hello ", " World"], ["Hello ", " World"]), 123);
 var h = tag(__makeTemplateObject(["Hello"], ["Hello"]));

tests/baselines/reference/checkJsObjectLiteralIndexSignatures.js

@@ -16,7 +16,7 @@ stringIndex[s].toFixed();
 // @ts-check
 var _a, _b;
 var n = Math.random();
-var s = "" + n;
+var s = "".concat(n);
 var numericIndex = (_a = {}, _a[n] = 1, _a);
 numericIndex[n].toFixed();
 var stringIndex = (_b = {}, _b[s] = 1, _b);

tests/baselines/reference/classAttributeInferenceTemplate.js

@@ -19,8 +19,8 @@ var MyClass = /** @class */ (function () {
     function MyClass() {
         var variable = 'something';
         this.property = "foo"; // Correctly inferred as `string`
-        this.property2 = "foo-" + variable; // Causes an error
-        var localProperty = "foo-" + variable; // Correctly inferred as `string`
+        this.property2 = "foo-".concat(variable); // Causes an error
+        var localProperty = "foo-".concat(variable); // Correctly inferred as `string`
     }
     return MyClass;
 }());

tests/baselines/reference/coAndContraVariantInferences.js

@@ -0,0 +1,74 @@
+//// [coAndContraVariantInferences.ts]
+type A = { kind: 'a' };
+type B = { kind: 'b' };
+
+declare const a: A;
+declare const b: B;
+
+declare function fab(arg: A | B): void;
+
+declare function foo<T>(x: { kind: T }, f: (arg: { kind: T }) => void): void;
+
+foo(a, fab);
+foo(b, fab);
+
+// Repro from #45603
+
+interface Action<TName extends string,TPayload> {
+    name: TName,
+    payload: TPayload
+}
+
+const actionA = { payload: 'any-string' } as Action<'ACTION_A', string>;
+const actionB = { payload: true } as Action<'ACTION_B', boolean>;
+
+function call<TName extends string,TPayload>(
+  action: Action<TName,TPayload>,
+  fn: (action: Action<TName,TPayload>)=> any,
+) {
+  fn(action);
+}
+
+const printFn = (action: typeof actionA | typeof actionB)=> console.log(action);
+
+call(actionA, printFn);
+call(actionB, printFn);
+
+
+//// [coAndContraVariantInferences.js]
+"use strict";
+foo(a, fab);
+foo(b, fab);
+var actionA = { payload: 'any-string' };
+var actionB = { payload: true };
+function call(action, fn) {
+    fn(action);
+}
+var printFn = function (action) { return console.log(action); };
+call(actionA, printFn);
+call(actionB, printFn);
+
+
+//// [coAndContraVariantInferences.d.ts]
+declare type A = {
+    kind: 'a';
+};
+declare type B = {
+    kind: 'b';
+};
+declare const a: A;
+declare const b: B;
+declare function fab(arg: A | B): void;
+declare function foo<T>(x: {
+    kind: T;
+}, f: (arg: {
+    kind: T;
+}) => void): void;
+interface Action<TName extends string, TPayload> {
+    name: TName;
+    payload: TPayload;
+}
+declare const actionA: Action<"ACTION_A", string>;
+declare const actionB: Action<"ACTION_B", boolean>;
+declare function call<TName extends string, TPayload>(action: Action<TName, TPayload>, fn: (action: Action<TName, TPayload>) => any): void;
+declare const printFn: (action: typeof actionA | typeof actionB) => void;

tests/baselines/reference/coAndContraVariantInferences.symbols

@@ -0,0 +1,114 @@
+=== tests/cases/compiler/coAndContraVariantInferences.ts ===
+type A = { kind: 'a' };
+>A : Symbol(A, Decl(coAndContraVariantInferences.ts, 0, 0))
+>kind : Symbol(kind, Decl(coAndContraVariantInferences.ts, 0, 10))
+
+type B = { kind: 'b' };
+>B : Symbol(B, Decl(coAndContraVariantInferences.ts, 0, 23))
+>kind : Symbol(kind, Decl(coAndContraVariantInferences.ts, 1, 10))
+
+declare const a: A;
+>a : Symbol(a, Decl(coAndContraVariantInferences.ts, 3, 13))
+>A : Symbol(A, Decl(coAndContraVariantInferences.ts, 0, 0))
+
+declare const b: B;
+>b : Symbol(b, Decl(coAndContraVariantInferences.ts, 4, 13))
+>B : Symbol(B, Decl(coAndContraVariantInferences.ts, 0, 23))
+
+declare function fab(arg: A | B): void;
+>fab : Symbol(fab, Decl(coAndContraVariantInferences.ts, 4, 19))
+>arg : Symbol(arg, Decl(coAndContraVariantInferences.ts, 6, 21))
+>A : Symbol(A, Decl(coAndContraVariantInferences.ts, 0, 0))
+>B : Symbol(B, Decl(coAndContraVariantInferences.ts, 0, 23))
+
+declare function foo<T>(x: { kind: T }, f: (arg: { kind: T }) => void): void;
+>foo : Symbol(foo, Decl(coAndContraVariantInferences.ts, 6, 39))
+>T : Symbol(T, Decl(coAndContraVariantInferences.ts, 8, 21))
+>x : Symbol(x, Decl(coAndContraVariantInferences.ts, 8, 24))
+>kind : Symbol(kind, Decl(coAndContraVariantInferences.ts, 8, 28))
+>T : Symbol(T, Decl(coAndContraVariantInferences.ts, 8, 21))
+>f : Symbol(f, Decl(coAndContraVariantInferences.ts, 8, 39))
+>arg : Symbol(arg, Decl(coAndContraVariantInferences.ts, 8, 44))
+>kind : Symbol(kind, Decl(coAndContraVariantInferences.ts, 8, 50))
+>T : Symbol(T, Decl(coAndContraVariantInferences.ts, 8, 21))
+
+foo(a, fab);
+>foo : Symbol(foo, Decl(coAndContraVariantInferences.ts, 6, 39))
+>a : Symbol(a, Decl(coAndContraVariantInferences.ts, 3, 13))
+>fab : Symbol(fab, Decl(coAndContraVariantInferences.ts, 4, 19))
+
+foo(b, fab);
+>foo : Symbol(foo, Decl(coAndContraVariantInferences.ts, 6, 39))
+>b : Symbol(b, Decl(coAndContraVariantInferences.ts, 4, 13))
+>fab : Symbol(fab, Decl(coAndContraVariantInferences.ts, 4, 19))
+
+// Repro from #45603
+
+interface Action<TName extends string,TPayload> {
+>Action : Symbol(Action, Decl(coAndContraVariantInferences.ts, 11, 12))
+>TName : Symbol(TName, Decl(coAndContraVariantInferences.ts, 15, 17))
+>TPayload : Symbol(TPayload, Decl(coAndContraVariantInferences.ts, 15, 38))
+
+    name: TName,
+>name : Symbol(Action.name, Decl(coAndContraVariantInferences.ts, 15, 49))
+>TName : Symbol(TName, Decl(coAndContraVariantInferences.ts, 15, 17))
+
+    payload: TPayload
+>payload : Symbol(Action.payload, Decl(coAndContraVariantInferences.ts, 16, 16))
+>TPayload : Symbol(TPayload, Decl(coAndContraVariantInferences.ts, 15, 38))
+}
+
+const actionA = { payload: 'any-string' } as Action<'ACTION_A', string>;
+>actionA : Symbol(actionA, Decl(coAndContraVariantInferences.ts, 20, 5))
+>payload : Symbol(payload, Decl(coAndContraVariantInferences.ts, 20, 17))
+>Action : Symbol(Action, Decl(coAndContraVariantInferences.ts, 11, 12))
+
+const actionB = { payload: true } as Action<'ACTION_B', boolean>;
+>actionB : Symbol(actionB, Decl(coAndContraVariantInferences.ts, 21, 5))
+>payload : Symbol(payload, Decl(coAndContraVariantInferences.ts, 21, 17))
+>Action : Symbol(Action, Decl(coAndContraVariantInferences.ts, 11, 12))
+
+function call<TName extends string,TPayload>(
+>call : Symbol(call, Decl(coAndContraVariantInferences.ts, 21, 65))
+>TName : Symbol(TName, Decl(coAndContraVariantInferences.ts, 23, 14))
+>TPayload : Symbol(TPayload, Decl(coAndContraVariantInferences.ts, 23, 35))
+
+  action: Action<TName,TPayload>,
+>action : Symbol(action, Decl(coAndContraVariantInferences.ts, 23, 45))
+>Action : Symbol(Action, Decl(coAndContraVariantInferences.ts, 11, 12))
+>TName : Symbol(TName, Decl(coAndContraVariantInferences.ts, 23, 14))
+>TPayload : Symbol(TPayload, Decl(coAndContraVariantInferences.ts, 23, 35))
+
+  fn: (action: Action<TName,TPayload>)=> any,
+>fn : Symbol(fn, Decl(coAndContraVariantInferences.ts, 24, 33))
+>action : Symbol(action, Decl(coAndContraVariantInferences.ts, 25, 7))
+>Action : Symbol(Action, Decl(coAndContraVariantInferences.ts, 11, 12))
+>TName : Symbol(TName, Decl(coAndContraVariantInferences.ts, 23, 14))
+>TPayload : Symbol(TPayload, Decl(coAndContraVariantInferences.ts, 23, 35))
+
+) {
+  fn(action);
+>fn : Symbol(fn, Decl(coAndContraVariantInferences.ts, 24, 33))
+>action : Symbol(action, Decl(coAndContraVariantInferences.ts, 23, 45))
+}
+
+const printFn = (action: typeof actionA | typeof actionB)=> console.log(action);
+>printFn : Symbol(printFn, Decl(coAndContraVariantInferences.ts, 30, 5))
+>action : Symbol(action, Decl(coAndContraVariantInferences.ts, 30, 17))
+>actionA : Symbol(actionA, Decl(coAndContraVariantInferences.ts, 20, 5))
+>actionB : Symbol(actionB, Decl(coAndContraVariantInferences.ts, 21, 5))
+>console.log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
+>console : Symbol(console, Decl(lib.dom.d.ts, --, --))
+>log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
+>action : Symbol(action, Decl(coAndContraVariantInferences.ts, 30, 17))
+
+call(actionA, printFn);
+>call : Symbol(call, Decl(coAndContraVariantInferences.ts, 21, 65))
+>actionA : Symbol(actionA, Decl(coAndContraVariantInferences.ts, 20, 5))
+>printFn : Symbol(printFn, Decl(coAndContraVariantInferences.ts, 30, 5))
+
+call(actionB, printFn);
+>call : Symbol(call, Decl(coAndContraVariantInferences.ts, 21, 65))
+>actionB : Symbol(actionB, Decl(coAndContraVariantInferences.ts, 21, 5))
+>printFn : Symbol(printFn, Decl(coAndContraVariantInferences.ts, 30, 5))
+

tests/baselines/reference/coAndContraVariantInferences.types

@@ -0,0 +1,104 @@
+=== tests/cases/compiler/coAndContraVariantInferences.ts ===
+type A = { kind: 'a' };
+>A : A
+>kind : "a"
+
+type B = { kind: 'b' };
+>B : B
+>kind : "b"
+
+declare const a: A;
+>a : A
+
+declare const b: B;
+>b : B
+
+declare function fab(arg: A | B): void;
+>fab : (arg: A | B) => void
+>arg : A | B
+
+declare function foo<T>(x: { kind: T }, f: (arg: { kind: T }) => void): void;
+>foo : <T>(x: {    kind: T;}, f: (arg: {    kind: T;}) => void) => void
+>x : { kind: T; }
+>kind : T
+>f : (arg: {    kind: T;}) => void
+>arg : { kind: T; }
+>kind : T
+
+foo(a, fab);
+>foo(a, fab) : void
+>foo : <T>(x: { kind: T; }, f: (arg: { kind: T; }) => void) => void
+>a : A
+>fab : (arg: A | B) => void
+
+foo(b, fab);
+>foo(b, fab) : void
+>foo : <T>(x: { kind: T; }, f: (arg: { kind: T; }) => void) => void
+>b : B
+>fab : (arg: A | B) => void
+
+// Repro from #45603
+
+interface Action<TName extends string,TPayload> {
+    name: TName,
+>name : TName
+
+    payload: TPayload
+>payload : TPayload
+}
+
+const actionA = { payload: 'any-string' } as Action<'ACTION_A', string>;
+>actionA : Action<"ACTION_A", string>
+>{ payload: 'any-string' } as Action<'ACTION_A', string> : Action<"ACTION_A", string>
+>{ payload: 'any-string' } : { payload: string; }
+>payload : string
+>'any-string' : "any-string"
+
+const actionB = { payload: true } as Action<'ACTION_B', boolean>;
+>actionB : Action<"ACTION_B", boolean>
+>{ payload: true } as Action<'ACTION_B', boolean> : Action<"ACTION_B", boolean>
+>{ payload: true } : { payload: true; }
+>payload : true
+>true : true
+
+function call<TName extends string,TPayload>(
+>call : <TName extends string, TPayload>(action: Action<TName, TPayload>, fn: (action: Action<TName, TPayload>) => any) => void
+
+  action: Action<TName,TPayload>,
+>action : Action<TName, TPayload>
+
+  fn: (action: Action<TName,TPayload>)=> any,
+>fn : (action: Action<TName, TPayload>) => any
+>action : Action<TName, TPayload>
+
+) {
+  fn(action);
+>fn(action) : any
+>fn : (action: Action<TName, TPayload>) => any
+>action : Action<TName, TPayload>
+}
+
+const printFn = (action: typeof actionA | typeof actionB)=> console.log(action);
+>printFn : (action: typeof actionA | typeof actionB) => void
+>(action: typeof actionA | typeof actionB)=> console.log(action) : (action: typeof actionA | typeof actionB) => void
+>action : Action<"ACTION_A", string> | Action<"ACTION_B", boolean>
+>actionA : Action<"ACTION_A", string>
+>actionB : Action<"ACTION_B", boolean>
+>console.log(action) : void
+>console.log : (...data: any[]) => void
+>console : Console
+>log : (...data: any[]) => void
+>action : Action<"ACTION_A", string> | Action<"ACTION_B", boolean>
+
+call(actionA, printFn);
+>call(actionA, printFn) : void
+>call : <TName extends string, TPayload>(action: Action<TName, TPayload>, fn: (action: Action<TName, TPayload>) => any) => void
+>actionA : Action<"ACTION_A", string>
+>printFn : (action: Action<"ACTION_A", string> | Action<"ACTION_B", boolean>) => void
+
+call(actionB, printFn);
+>call(actionB, printFn) : void
+>call : <TName extends string, TPayload>(action: Action<TName, TPayload>, fn: (action: Action<TName, TPayload>) => any) => void
+>actionB : Action<"ACTION_B", boolean>
+>printFn : (action: Action<"ACTION_A", string> | Action<"ACTION_B", boolean>) => void
+

tests/baselines/reference/complicatedIndexedAccessKeyofReliesOnKeyofNeverUpperBound.errors.txt

@@ -9,16 +9,14 @@ tests/cases/compiler/complicatedIndexedAccessKeyofReliesOnKeyofNeverUpperBound.t
                 Type '"text" | "email"' is not assignable to type 'ChannelOfType<T, TextChannel>["type"]'.
                   Type '"text"' is not assignable to type 'ChannelOfType<T, TextChannel>["type"]'.
                     Type '"text"' is not assignable to type 'T & "text"'.
-                      Type '"text"' is not assignable to type 'T'.
-                        '"text"' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint '"text" | "email"'.
-                          Type 'T' is not assignable to type 'T & "text"'.
-                            Type '"text" | "email"' is not assignable to type 'T & "text"'.
-                              Type '"text"' is not assignable to type 'T & "text"'.
-                                Type '"text"' is not assignable to type 'T'.
-                                  '"text"' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint '"text" | "email"'.
-                                    Type 'T' is not assignable to type '"text"'.
-                                      Type '"text" | "email"' is not assignable to type '"text"'.
-                                        Type '"email"' is not assignable to type '"text"'.
+                      Type 'T' is not assignable to type 'T & "text"'.
+                        Type '"text" | "email"' is not assignable to type 'T & "text"'.
+                          Type '"text"' is not assignable to type 'T & "text"'.
+                            Type '"text"' is not assignable to type 'T'.
+                              '"text"' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint '"text" | "email"'.
+                                Type 'T' is not assignable to type '"text"'.
+                                  Type '"text" | "email"' is not assignable to type '"text"'.
+                                    Type '"email"' is not assignable to type '"text"'.
 
 
 ==== tests/cases/compiler/complicatedIndexedAccessKeyofReliesOnKeyofNeverUpperBound.ts (1 errors) ====
@@ -67,16 +65,14 @@ tests/cases/compiler/complicatedIndexedAccessKeyofReliesOnKeyofNeverUpperBound.t
 !!! error TS2322:                 Type '"text" | "email"' is not assignable to type 'ChannelOfType<T, TextChannel>["type"]'.
 !!! error TS2322:                   Type '"text"' is not assignable to type 'ChannelOfType<T, TextChannel>["type"]'.
 !!! error TS2322:                     Type '"text"' is not assignable to type 'T & "text"'.
-!!! error TS2322:                       Type '"text"' is not assignable to type 'T'.
-!!! error TS2322:                         '"text"' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint '"text" | "email"'.
-!!! error TS2322:                           Type 'T' is not assignable to type 'T & "text"'.
-!!! error TS2322:                             Type '"text" | "email"' is not assignable to type 'T & "text"'.
-!!! error TS2322:                               Type '"text"' is not assignable to type 'T & "text"'.
-!!! error TS2322:                                 Type '"text"' is not assignable to type 'T'.
-!!! error TS2322:                                   '"text"' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint '"text" | "email"'.
-!!! error TS2322:                                     Type 'T' is not assignable to type '"text"'.
-!!! error TS2322:                                       Type '"text" | "email"' is not assignable to type '"text"'.
-!!! error TS2322:                                         Type '"email"' is not assignable to type '"text"'.
+!!! error TS2322:                       Type 'T' is not assignable to type 'T & "text"'.
+!!! error TS2322:                         Type '"text" | "email"' is not assignable to type 'T & "text"'.
+!!! error TS2322:                           Type '"text"' is not assignable to type 'T & "text"'.
+!!! error TS2322:                             Type '"text"' is not assignable to type 'T'.
+!!! error TS2322:                               '"text"' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint '"text" | "email"'.
+!!! error TS2322:                                 Type 'T' is not assignable to type '"text"'.
+!!! error TS2322:                                   Type '"text" | "email"' is not assignable to type '"text"'.
+!!! error TS2322:                                     Type '"email"' is not assignable to type '"text"'.
     }
     
     const newTextChannel = makeNewChannel('text');

tests/baselines/reference/computedPropertyNames10_ES5.js

@@ -32,5 +32,5 @@ var v = (_a = {},
     _a[a] = function () { },
     _a[true] = function () { },
     _a["hello bye"] = function () { },
-    _a["hello " + a + " bye"] = function () { },
+    _a["hello ".concat(a, " bye")] = function () { },
     _a);

tests/baselines/reference/computedPropertyNames11_ES5.js

@@ -72,7 +72,7 @@ var v = (_a = {},
         enumerable: false,
         configurable: true
     }),
-    Object.defineProperty(_a, "hello " + a + " bye", {
+    Object.defineProperty(_a, "hello ".concat(a, " bye"), {
         get: function () { return 0; },
         enumerable: false,
         configurable: true

tests/baselines/reference/computedPropertyNames12_ES5.js

@@ -27,7 +27,7 @@ var C = /** @class */ (function () {
         this["hello bye"] = 0;
     }
     var _a, _b, _c;
-    _a = n, s + s, _b = s + n, +s, _c = "hello " + a + " bye";
+    _a = n, s + s, _b = s + n, +s, _c = "hello ".concat(a, " bye");
     C[_c] = 0;
     return C;
 }());

tests/baselines/reference/computedPropertyNames13_ES5.js

@@ -33,6 +33,6 @@ var C = /** @class */ (function () {
     C.prototype[a] = function () { };
     C[true] = function () { };
     C.prototype["hello bye"] = function () { };
-    C["hello " + a + " bye"] = function () { };
+    C["hello ".concat(a, " bye")] = function () { };
     return C;
 }());

tests/baselines/reference/computedPropertyNames16_ES5.js

@@ -73,7 +73,7 @@ var C = /** @class */ (function () {
         enumerable: false,
         configurable: true
     });
-    Object.defineProperty(C.prototype, "hello " + a + " bye", {
+    Object.defineProperty(C.prototype, "hello ".concat(a, " bye"), {
         get: function () { return 0; },
         enumerable: false,
         configurable: true

tests/baselines/reference/computedPropertyNames4_ES5.js

@@ -32,5 +32,5 @@ var v = (_a = {},
     _a[a] = 1,
     _a[true] = 0,
     _a["hello bye"] = 0,
-    _a["hello " + a + " bye"] = 0,
+    _a["hello ".concat(a, " bye")] = 0,
     _a);

tests/baselines/reference/constEnumErrors.js

@@ -52,7 +52,7 @@ var E;
 var y0 = E2[1];
 var name = "A";
 var y1 = E2[name];
-var y2 = E2["" + name];
+var y2 = E2["".concat(name)];
 var x = E2;
 var y = [E2];
 function foo(t) {

tests/baselines/reference/controlFlowGenericTypes.errors.txt

@@ -220,4 +220,24 @@ tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(168,9): error TS2
             this.validateRow(row);
         }
     }
+    
+    // Repro from #46495
+    
+    interface Button {
+        type: "button";
+        text: string;
+    }
+    
+    interface Checkbox {
+        type: "checkbox";
+        isChecked: boolean;
+    }
+    
+    type Control = Button | Checkbox;
+    
+    function update<T extends Control, K extends keyof T>(control : T | undefined, key: K, value: T[K]): void {
+        if (control !== undefined) {
+            control[key] = value;
+        }
+    }
     

tests/baselines/reference/controlFlowGenericTypes.js

@@ -190,6 +190,26 @@ class SqlTable<T> {
         this.validateRow(row);
     }
 }
+
+// Repro from #46495
+
+interface Button {
+    type: "button";
+    text: string;
+}
+
+interface Checkbox {
+    type: "checkbox";
+    isChecked: boolean;
+}
+
+type Control = Button | Checkbox;
+
+function update<T extends Control, K extends keyof T>(control : T | undefined, key: K, value: T[K]): void {
+    if (control !== undefined) {
+        control[key] = value;
+    }
+}
 
 
 //// [controlFlowGenericTypes.js]
@@ -343,3 +363,8 @@ var SqlTable = /** @class */ (function () {
     };
     return SqlTable;
 }());
+function update(control, key, value) {
+    if (control !== undefined) {
+        control[key] = value;
+    }
+}

tests/baselines/reference/controlFlowGenericTypes.symbols

@@ -574,3 +574,55 @@ class SqlTable<T> {
     }
 }
 
+// Repro from #46495
+
+interface Button {
+>Button : Symbol(Button, Decl(controlFlowGenericTypes.ts, 190, 1))
+
+    type: "button";
+>type : Symbol(Button.type, Decl(controlFlowGenericTypes.ts, 194, 18))
+
+    text: string;
+>text : Symbol(Button.text, Decl(controlFlowGenericTypes.ts, 195, 19))
+}
+
+interface Checkbox {
+>Checkbox : Symbol(Checkbox, Decl(controlFlowGenericTypes.ts, 197, 1))
+
+    type: "checkbox";
+>type : Symbol(Checkbox.type, Decl(controlFlowGenericTypes.ts, 199, 20))
+
+    isChecked: boolean;
+>isChecked : Symbol(Checkbox.isChecked, Decl(controlFlowGenericTypes.ts, 200, 21))
+}
+
+type Control = Button | Checkbox;
+>Control : Symbol(Control, Decl(controlFlowGenericTypes.ts, 202, 1))
+>Button : Symbol(Button, Decl(controlFlowGenericTypes.ts, 190, 1))
+>Checkbox : Symbol(Checkbox, Decl(controlFlowGenericTypes.ts, 197, 1))
+
+function update<T extends Control, K extends keyof T>(control : T | undefined, key: K, value: T[K]): void {
+>update : Symbol(update, Decl(controlFlowGenericTypes.ts, 204, 33))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 206, 16))
+>Control : Symbol(Control, Decl(controlFlowGenericTypes.ts, 202, 1))
+>K : Symbol(K, Decl(controlFlowGenericTypes.ts, 206, 34))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 206, 16))
+>control : Symbol(control, Decl(controlFlowGenericTypes.ts, 206, 54))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 206, 16))
+>key : Symbol(key, Decl(controlFlowGenericTypes.ts, 206, 78))
+>K : Symbol(K, Decl(controlFlowGenericTypes.ts, 206, 34))
+>value : Symbol(value, Decl(controlFlowGenericTypes.ts, 206, 86))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 206, 16))
+>K : Symbol(K, Decl(controlFlowGenericTypes.ts, 206, 34))
+
+    if (control !== undefined) {
+>control : Symbol(control, Decl(controlFlowGenericTypes.ts, 206, 54))
+>undefined : Symbol(undefined)
+
+        control[key] = value;
+>control : Symbol(control, Decl(controlFlowGenericTypes.ts, 206, 54))
+>key : Symbol(key, Decl(controlFlowGenericTypes.ts, 206, 78))
+>value : Symbol(value, Decl(controlFlowGenericTypes.ts, 206, 86))
+    }
+}
+

tests/baselines/reference/controlFlowGenericTypes.types

@@ -542,3 +542,44 @@ class SqlTable<T> {
     }
 }
 
+// Repro from #46495
+
+interface Button {
+    type: "button";
+>type : "button"
+
+    text: string;
+>text : string
+}
+
+interface Checkbox {
+    type: "checkbox";
+>type : "checkbox"
+
+    isChecked: boolean;
+>isChecked : boolean
+}
+
+type Control = Button | Checkbox;
+>Control : Control
+
+function update<T extends Control, K extends keyof T>(control : T | undefined, key: K, value: T[K]): void {
+>update : <T extends Control, K extends keyof T>(control: T | undefined, key: K, value: T[K]) => void
+>control : T | undefined
+>key : K
+>value : T[K]
+
+    if (control !== undefined) {
+>control !== undefined : boolean
+>control : T | undefined
+>undefined : undefined
+
+        control[key] = value;
+>control[key] = value : T[K]
+>control[key] : T[K]
+>control : T
+>key : K
+>value : T[K]
+    }
+}
+

tests/baselines/reference/declarationNoDanglingGenerics.js

@@ -54,7 +54,7 @@ exports.CKind = exports.BKind = exports.AKind = void 0;
 var kindCache = {};
 function register(kind) {
     if (kindCache[kind]) {
-        throw new Error("Class with kind \"" + kind + "\" is already registered.");
+        throw new Error("Class with kind \"".concat(kind, "\" is already registered."));
     }
     kindCache[kind] = true;
 }

tests/baselines/reference/deepComparisons.errors.txt

@@ -46,4 +46,23 @@ tests/cases/compiler/deepComparisons.ts(4,9): error TS2322: Type 'T[K1][K2]' is
     
     function f3<U>() {
         let x: Foo1<U> = 0 as any as Bar<U>;  // No error!
-    }
+    }
+    
+    // Repro from #46500
+    
+    type F<T> = {} & (
+        T extends [any, ...any[]]
+            ? { [K in keyof T]?: F<T[K]> }
+            : T extends any[]
+                ? F<T[number]>[]
+                : T extends { [K: string]: any }
+                    ? { [K in keyof T]?: F<T[K]> }
+                    : { x: string }
+    );
+    
+    declare function f<T = any>(): F<T>;
+    
+    function g() {
+        return f() as F<any>;
+    }
+    

tests/baselines/reference/deepComparisons.js

@@ -17,7 +17,26 @@ type Foo2<T> = { x: Foo1<T> };
 
 function f3<U>() {
     let x: Foo1<U> = 0 as any as Bar<U>;  // No error!
-}
+}
+
+// Repro from #46500
+
+type F<T> = {} & (
+    T extends [any, ...any[]]
+        ? { [K in keyof T]?: F<T[K]> }
+        : T extends any[]
+            ? F<T[number]>[]
+            : T extends { [K: string]: any }
+                ? { [K in keyof T]?: F<T[K]> }
+                : { x: string }
+);
+
+declare function f<T = any>(): F<T>;
+
+function g() {
+    return f() as F<any>;
+}
+
 
 //// [deepComparisons.js]
 function f1() {
@@ -31,3 +50,6 @@ function f2() {
 function f3() {
     var x = 0; // No error!
 }
+function g() {
+    return f();
+}

tests/baselines/reference/deepComparisons.symbols

@@ -84,3 +84,57 @@ function f3<U>() {
 >Bar : Symbol(Bar, Decl(deepComparisons.ts, 6, 28))
 >U : Symbol(U, Decl(deepComparisons.ts, 16, 12))
 }
+
+// Repro from #46500
+
+type F<T> = {} & (
+>F : Symbol(F, Decl(deepComparisons.ts, 18, 1))
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+
+    T extends [any, ...any[]]
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+
+        ? { [K in keyof T]?: F<T[K]> }
+>K : Symbol(K, Decl(deepComparisons.ts, 24, 13))
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+>F : Symbol(F, Decl(deepComparisons.ts, 18, 1))
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+>K : Symbol(K, Decl(deepComparisons.ts, 24, 13))
+
+        : T extends any[]
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+
+            ? F<T[number]>[]
+>F : Symbol(F, Decl(deepComparisons.ts, 18, 1))
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+
+            : T extends { [K: string]: any }
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+>K : Symbol(K, Decl(deepComparisons.ts, 27, 27))
+
+                ? { [K in keyof T]?: F<T[K]> }
+>K : Symbol(K, Decl(deepComparisons.ts, 28, 21))
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+>F : Symbol(F, Decl(deepComparisons.ts, 18, 1))
+>T : Symbol(T, Decl(deepComparisons.ts, 22, 7))
+>K : Symbol(K, Decl(deepComparisons.ts, 28, 21))
+
+                : { x: string }
+>x : Symbol(x, Decl(deepComparisons.ts, 29, 19))
+
+);
+
+declare function f<T = any>(): F<T>;
+>f : Symbol(f, Decl(deepComparisons.ts, 30, 2))
+>T : Symbol(T, Decl(deepComparisons.ts, 32, 19))
+>F : Symbol(F, Decl(deepComparisons.ts, 18, 1))
+>T : Symbol(T, Decl(deepComparisons.ts, 32, 19))
+
+function g() {
+>g : Symbol(g, Decl(deepComparisons.ts, 32, 36))
+
+    return f() as F<any>;
+>f : Symbol(f, Decl(deepComparisons.ts, 30, 2))
+>F : Symbol(F, Decl(deepComparisons.ts, 18, 1))
+}
+

tests/baselines/reference/deepComparisons.types

@@ -56,3 +56,34 @@ function f3<U>() {
 >0 as any : any
 >0 : 0
 }
+
+// Repro from #46500
+
+type F<T> = {} & (
+>F : F<T>
+
+    T extends [any, ...any[]]
+        ? { [K in keyof T]?: F<T[K]> }
+        : T extends any[]
+            ? F<T[number]>[]
+            : T extends { [K: string]: any }
+>K : string
+
+                ? { [K in keyof T]?: F<T[K]> }
+                : { x: string }
+>x : string
+
+);
+
+declare function f<T = any>(): F<T>;
+>f : <T = any>() => F<T>
+
+function g() {
+>g : () => F<any>
+
+    return f() as F<any>;
+>f() as F<any> : F<any>
+>f() : F<any>
+>f : <T = any>() => F<T>
+}
+

tests/baselines/reference/destructuringInitializerContextualTypeFromContext.js

@@ -55,7 +55,7 @@ var Parent = function (_a) {
 };
 var Child = function (_a) {
     var children = _a.children, _b = _a.name, name = _b === void 0 ? "Artemis" : _b, props = __rest(_a, ["children", "name"]);
-    return "name: " + name + " props: " + JSON.stringify(props);
+    return "name: ".concat(name, " props: ").concat(JSON.stringify(props));
 };
 f(function (_a) {
     var _1 = _a[0], _b = _a[1], _2 = _b === void 0 ? undefined : _b;

tests/baselines/reference/discriminatedUnionJsxElement.js

@@ -0,0 +1,57 @@
+//// [discriminatedUnionJsxElement.tsx]
+// Repro from #46021
+
+interface IData<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine> {
+    menuItemsVariant?: MenuItemVariant;
+}
+
+function Menu<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine>(data: IData<MenuItemVariant>) {
+    const listItemVariant = data.menuItemsVariant ?? ListItemVariant.OneLine;
+    return <ListItem variant={listItemVariant} />;
+}
+
+type IListItemData = { variant: ListItemVariant.Avatar; } | { variant: ListItemVariant.OneLine; };
+
+enum ListItemVariant {
+    OneLine,
+    Avatar,
+}
+
+function ListItem(_data: IListItemData) {
+    return null; 
+}
+
+
+//// [discriminatedUnionJsxElement.jsx]
+"use strict";
+// Repro from #46021
+function Menu(data) {
+    var _a;
+    var listItemVariant = (_a = data.menuItemsVariant) !== null && _a !== void 0 ? _a : ListItemVariant.OneLine;
+    return <ListItem variant={listItemVariant}/>;
+}
+var ListItemVariant;
+(function (ListItemVariant) {
+    ListItemVariant[ListItemVariant["OneLine"] = 0] = "OneLine";
+    ListItemVariant[ListItemVariant["Avatar"] = 1] = "Avatar";
+})(ListItemVariant || (ListItemVariant = {}));
+function ListItem(_data) {
+    return null;
+}
+
+
+//// [discriminatedUnionJsxElement.d.ts]
+interface IData<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine> {
+    menuItemsVariant?: MenuItemVariant;
+}
+declare function Menu<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine>(data: IData<MenuItemVariant>): any;
+declare type IListItemData = {
+    variant: ListItemVariant.Avatar;
+} | {
+    variant: ListItemVariant.OneLine;
+};
+declare enum ListItemVariant {
+    OneLine = 0,
+    Avatar = 1
+}
+declare function ListItem(_data: IListItemData): null;

tests/baselines/reference/discriminatedUnionJsxElement.symbols

@@ -0,0 +1,67 @@
+=== tests/cases/compiler/discriminatedUnionJsxElement.tsx ===
+// Repro from #46021
+
+interface IData<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine> {
+>IData : Symbol(IData, Decl(discriminatedUnionJsxElement.tsx, 0, 0))
+>MenuItemVariant : Symbol(MenuItemVariant, Decl(discriminatedUnionJsxElement.tsx, 2, 16))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>OneLine : Symbol(ListItemVariant.OneLine, Decl(discriminatedUnionJsxElement.tsx, 13, 22))
+
+    menuItemsVariant?: MenuItemVariant;
+>menuItemsVariant : Symbol(IData.menuItemsVariant, Decl(discriminatedUnionJsxElement.tsx, 2, 84))
+>MenuItemVariant : Symbol(MenuItemVariant, Decl(discriminatedUnionJsxElement.tsx, 2, 16))
+}
+
+function Menu<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine>(data: IData<MenuItemVariant>) {
+>Menu : Symbol(Menu, Decl(discriminatedUnionJsxElement.tsx, 4, 1))
+>MenuItemVariant : Symbol(MenuItemVariant, Decl(discriminatedUnionJsxElement.tsx, 6, 14))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>OneLine : Symbol(ListItemVariant.OneLine, Decl(discriminatedUnionJsxElement.tsx, 13, 22))
+>data : Symbol(data, Decl(discriminatedUnionJsxElement.tsx, 6, 81))
+>IData : Symbol(IData, Decl(discriminatedUnionJsxElement.tsx, 0, 0))
+>MenuItemVariant : Symbol(MenuItemVariant, Decl(discriminatedUnionJsxElement.tsx, 6, 14))
+
+    const listItemVariant = data.menuItemsVariant ?? ListItemVariant.OneLine;
+>listItemVariant : Symbol(listItemVariant, Decl(discriminatedUnionJsxElement.tsx, 7, 9))
+>data.menuItemsVariant : Symbol(IData.menuItemsVariant, Decl(discriminatedUnionJsxElement.tsx, 2, 84))
+>data : Symbol(data, Decl(discriminatedUnionJsxElement.tsx, 6, 81))
+>menuItemsVariant : Symbol(IData.menuItemsVariant, Decl(discriminatedUnionJsxElement.tsx, 2, 84))
+>ListItemVariant.OneLine : Symbol(ListItemVariant.OneLine, Decl(discriminatedUnionJsxElement.tsx, 13, 22))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>OneLine : Symbol(ListItemVariant.OneLine, Decl(discriminatedUnionJsxElement.tsx, 13, 22))
+
+    return <ListItem variant={listItemVariant} />;
+>ListItem : Symbol(ListItem, Decl(discriminatedUnionJsxElement.tsx, 16, 1))
+>variant : Symbol(variant, Decl(discriminatedUnionJsxElement.tsx, 8, 20))
+>listItemVariant : Symbol(listItemVariant, Decl(discriminatedUnionJsxElement.tsx, 7, 9))
+}
+
+type IListItemData = { variant: ListItemVariant.Avatar; } | { variant: ListItemVariant.OneLine; };
+>IListItemData : Symbol(IListItemData, Decl(discriminatedUnionJsxElement.tsx, 9, 1))
+>variant : Symbol(variant, Decl(discriminatedUnionJsxElement.tsx, 11, 22))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>Avatar : Symbol(ListItemVariant.Avatar, Decl(discriminatedUnionJsxElement.tsx, 14, 12))
+>variant : Symbol(variant, Decl(discriminatedUnionJsxElement.tsx, 11, 61))
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+>OneLine : Symbol(ListItemVariant.OneLine, Decl(discriminatedUnionJsxElement.tsx, 13, 22))
+
+enum ListItemVariant {
+>ListItemVariant : Symbol(ListItemVariant, Decl(discriminatedUnionJsxElement.tsx, 11, 98))
+
+    OneLine,
+>OneLine : Symbol(ListItemVariant.OneLine, Decl(discriminatedUnionJsxElement.tsx, 13, 22))
+
+    Avatar,
+>Avatar : Symbol(ListItemVariant.Avatar, Decl(discriminatedUnionJsxElement.tsx, 14, 12))
+}
+
+function ListItem(_data: IListItemData) {
+>ListItem : Symbol(ListItem, Decl(discriminatedUnionJsxElement.tsx, 16, 1))
+>_data : Symbol(_data, Decl(discriminatedUnionJsxElement.tsx, 18, 18))
+>IListItemData : Symbol(IListItemData, Decl(discriminatedUnionJsxElement.tsx, 9, 1))
+
+    return null; 
+}
+

tests/baselines/reference/discriminatedUnionJsxElement.types

@@ -0,0 +1,57 @@
+=== tests/cases/compiler/discriminatedUnionJsxElement.tsx ===
+// Repro from #46021
+
+interface IData<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine> {
+>ListItemVariant : any
+
+    menuItemsVariant?: MenuItemVariant;
+>menuItemsVariant : MenuItemVariant | undefined
+}
+
+function Menu<MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine>(data: IData<MenuItemVariant>) {
+>Menu : <MenuItemVariant extends ListItemVariant = ListItemVariant.OneLine>(data: IData<MenuItemVariant>) => any
+>ListItemVariant : any
+>data : IData<MenuItemVariant>
+
+    const listItemVariant = data.menuItemsVariant ?? ListItemVariant.OneLine;
+>listItemVariant : ListItemVariant.OneLine | NonNullable<MenuItemVariant>
+>data.menuItemsVariant ?? ListItemVariant.OneLine : ListItemVariant.OneLine | NonNullable<MenuItemVariant>
+>data.menuItemsVariant : MenuItemVariant | undefined
+>data : IData<MenuItemVariant>
+>menuItemsVariant : MenuItemVariant | undefined
+>ListItemVariant.OneLine : ListItemVariant.OneLine
+>ListItemVariant : typeof ListItemVariant
+>OneLine : ListItemVariant.OneLine
+
+    return <ListItem variant={listItemVariant} />;
+><ListItem variant={listItemVariant} /> : error
+>ListItem : (_data: IListItemData) => null
+>variant : ListItemVariant
+>listItemVariant : ListItemVariant
+}
+
+type IListItemData = { variant: ListItemVariant.Avatar; } | { variant: ListItemVariant.OneLine; };
+>IListItemData : IListItemData
+>variant : ListItemVariant.Avatar
+>ListItemVariant : any
+>variant : ListItemVariant.OneLine
+>ListItemVariant : any
+
+enum ListItemVariant {
+>ListItemVariant : ListItemVariant
+
+    OneLine,
+>OneLine : ListItemVariant.OneLine
+
+    Avatar,
+>Avatar : ListItemVariant.Avatar
+}
+
+function ListItem(_data: IListItemData) {
+>ListItem : (_data: IListItemData) => null
+>_data : IListItemData
+
+    return null; 
+>null : null
+}
+

tests/baselines/reference/emitExponentiationOperatorInTempalteString4.js

@@ -31,22 +31,22 @@ var t1 = 10;
 var t2 = 10;
 var s;
 // With TemplateTail
-Math.pow(t1, -t2) + " world";
-Math.pow((-t1), t2) - t1 + " world";
-Math.pow((-++t1), t2) - t1 + " world";
-Math.pow((-t1++), t2) - t1 + " world";
-Math.pow((~t1), Math.pow(t2, --t1)) + " world";
-typeof (Math.pow(t1, Math.pow(t2, t1))) + " world";
+"".concat(Math.pow(t1, -t2), " world");
+"".concat(Math.pow((-t1), t2) - t1, " world");
+"".concat(Math.pow((-++t1), t2) - t1, " world");
+"".concat(Math.pow((-t1++), t2) - t1, " world");
+"".concat(Math.pow((~t1), Math.pow(t2, --t1)), " world");
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " world");
 // TempateHead & TemplateTail are empt
-Math.pow(t1, -t2) + " hello world " + Math.pow(t1, -t2);
-Math.pow((-t1), t2) - t1 + " hello world " + (Math.pow((-t1), t2) - t1);
-Math.pow((-++t1), t2) - t1 + " hello world " + Math.pow(t1, Math.pow((-++t1), -t1));
-Math.pow((-t1++), t2) - t1 + " hello world " + Math.pow(t2, Math.pow((-t1++), -t1));
-Math.pow((~t1), Math.pow(t2, --t1)) + " hello world " + Math.pow((~t1), Math.pow(t2, --t1));
-typeof (Math.pow(t1, Math.pow(t2, t1))) + " hello world " + typeof (Math.pow(t1, Math.pow(t2, t1)));
+"".concat(Math.pow(t1, -t2), " hello world ").concat(Math.pow(t1, -t2));
+"".concat(Math.pow((-t1), t2) - t1, " hello world ").concat(Math.pow((-t1), t2) - t1);
+"".concat(Math.pow((-++t1), t2) - t1, " hello world ").concat(Math.pow(t1, Math.pow((-++t1), -t1)));
+"".concat(Math.pow((-t1++), t2) - t1, " hello world ").concat(Math.pow(t2, Math.pow((-t1++), -t1)));
+"".concat(Math.pow((~t1), Math.pow(t2, --t1)), " hello world ").concat(Math.pow((~t1), Math.pow(t2, --t1)));
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " hello world ").concat(typeof (Math.pow(t1, Math.pow(t2, t1))));
 // With templateHead
-"hello " + (Math.pow((-t1), t2) - t1);
-"hello " + (Math.pow((-++t1), t2) - t1);
-"hello " + (Math.pow((-t1++), t2) - t1);
-"hello " + Math.pow((~t1), Math.pow(t2, --t1));
-"hello " + typeof (Math.pow(t1, Math.pow(t2, t1)));
+"hello ".concat(Math.pow((-t1), t2) - t1);
+"hello ".concat(Math.pow((-++t1), t2) - t1);
+"hello ".concat(Math.pow((-t1++), t2) - t1);
+"hello ".concat(Math.pow((~t1), Math.pow(t2, --t1)));
+"hello ".concat(typeof (Math.pow(t1, Math.pow(t2, t1))));

tests/baselines/reference/emitExponentiationOperatorInTemplateString1.js

@@ -31,22 +31,22 @@ var t1 = 10;
 var t2 = 10;
 var s;
 // TempateHead & TemplateTail are empty
-"" + Math.pow(t1, t2);
-"" + Math.pow(t1, Math.pow(t2, t1));
-"" + (t1 + Math.pow(t2, t1));
-"" + (Math.pow(t1, t2) + t1);
-"" + (t1 + Math.pow(t2, t2) + t1);
-"" + typeof (Math.pow(t1, Math.pow(t2, t1)));
-"" + (1 + typeof (Math.pow(t1, Math.pow(t2, t1))));
-"" + Math.pow(t1, t2) + Math.pow(t1, t2);
-"" + Math.pow(t1, Math.pow(t2, t1)) + Math.pow(t1, Math.pow(t2, t1));
-"" + (t1 + Math.pow(t2, t1)) + (t1 + Math.pow(t2, t1));
-"" + (Math.pow(t1, t2) + t1) + (Math.pow(t1, t2) + t1);
-"" + (t1 + Math.pow(t2, t2) + t1) + (t1 + Math.pow(t2, t2) + t1);
-"" + typeof (Math.pow(t1, Math.pow(t2, t1))) + typeof (Math.pow(t1, Math.pow(t2, t1)));
-Math.pow(t1, t2) + " hello world " + Math.pow(t1, t2);
-Math.pow(t1, Math.pow(t2, t1)) + " hello world " + Math.pow(t1, Math.pow(t2, t1));
-t1 + Math.pow(t2, t1) + " hello world " + (t1 + Math.pow(t2, t1));
-Math.pow(t1, t2) + t1 + " hello world " + (Math.pow(t1, t2) + t1);
-t1 + Math.pow(t2, t2) + t1 + " hello world " + (t1 + Math.pow(t2, t2) + t1);
-typeof (Math.pow(t1, Math.pow(t2, t1))) + " hello world " + typeof (Math.pow(t1, Math.pow(t2, t1)));
+"".concat(Math.pow(t1, t2));
+"".concat(Math.pow(t1, Math.pow(t2, t1)));
+"".concat(t1 + Math.pow(t2, t1));
+"".concat(Math.pow(t1, t2) + t1);
+"".concat(t1 + Math.pow(t2, t2) + t1);
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1))));
+"".concat(1 + typeof (Math.pow(t1, Math.pow(t2, t1))));
+"".concat(Math.pow(t1, t2)).concat(Math.pow(t1, t2));
+"".concat(Math.pow(t1, Math.pow(t2, t1))).concat(Math.pow(t1, Math.pow(t2, t1)));
+"".concat(t1 + Math.pow(t2, t1)).concat(t1 + Math.pow(t2, t1));
+"".concat(Math.pow(t1, t2) + t1).concat(Math.pow(t1, t2) + t1);
+"".concat(t1 + Math.pow(t2, t2) + t1).concat(t1 + Math.pow(t2, t2) + t1);
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1)))).concat(typeof (Math.pow(t1, Math.pow(t2, t1))));
+"".concat(Math.pow(t1, t2), " hello world ").concat(Math.pow(t1, t2));
+"".concat(Math.pow(t1, Math.pow(t2, t1)), " hello world ").concat(Math.pow(t1, Math.pow(t2, t1)));
+"".concat(t1 + Math.pow(t2, t1), " hello world ").concat(t1 + Math.pow(t2, t1));
+"".concat(Math.pow(t1, t2) + t1, " hello world ").concat(Math.pow(t1, t2) + t1);
+"".concat(t1 + Math.pow(t2, t2) + t1, " hello world ").concat(t1 + Math.pow(t2, t2) + t1);
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " hello world ").concat(typeof (Math.pow(t1, Math.pow(t2, t1))));

tests/baselines/reference/emitExponentiationOperatorInTemplateString2.js

@@ -31,22 +31,22 @@ var t1 = 10;
 var t2 = 10;
 var s;
 // With templateHead
-"hello " + Math.pow(t1, t2);
-"hello " + Math.pow(t1, Math.pow(t2, t1));
-"hello " + (t1 + Math.pow(t2, t1));
-"hello " + (Math.pow(t1, t2) + t1);
-"hello " + (t1 + Math.pow(t2, t2) + t1);
-"hello " + typeof (Math.pow(t1, Math.pow(t2, t1)));
-"hello " + (1 + typeof (Math.pow(t1, Math.pow(t2, t1))));
-"hello " + Math.pow(t1, t2) + Math.pow(t1, t2);
-"hello " + Math.pow(t1, Math.pow(t2, t1)) + Math.pow(t1, Math.pow(t2, t1));
-"hello " + (t1 + Math.pow(t2, t1)) + (t1 + Math.pow(t2, t1));
-"hello " + (Math.pow(t1, t2) + t1) + (Math.pow(t1, t2) + t1);
-"hello " + (t1 + Math.pow(t2, t2) + t1) + (t1 + Math.pow(t2, t2) + t1);
-"hello " + typeof (Math.pow(t1, Math.pow(t2, t1))) + typeof (Math.pow(t1, Math.pow(t2, t1)));
-"hello " + Math.pow(t1, t2) + " hello world " + Math.pow(t1, t2);
-"hello " + Math.pow(t1, Math.pow(t2, t1)) + " hello world " + Math.pow(t1, Math.pow(t2, t1));
-"hello " + (t1 + Math.pow(t2, t1)) + " hello world " + (t1 + Math.pow(t2, t1));
-"hello " + (Math.pow(t1, t2) + t1) + " hello world " + (Math.pow(t1, t2) + t1);
-"hello " + (t1 + Math.pow(t2, t2) + t1) + " hello world " + (t1 + Math.pow(t2, t2) + t1);
-"hello " + typeof (Math.pow(t1, Math.pow(t2, t1))) + " hello world " + typeof (Math.pow(t1, Math.pow(t2, t1)));
+"hello ".concat(Math.pow(t1, t2));
+"hello ".concat(Math.pow(t1, Math.pow(t2, t1)));
+"hello ".concat(t1 + Math.pow(t2, t1));
+"hello ".concat(Math.pow(t1, t2) + t1);
+"hello ".concat(t1 + Math.pow(t2, t2) + t1);
+"hello ".concat(typeof (Math.pow(t1, Math.pow(t2, t1))));
+"hello ".concat(1 + typeof (Math.pow(t1, Math.pow(t2, t1))));
+"hello ".concat(Math.pow(t1, t2)).concat(Math.pow(t1, t2));
+"hello ".concat(Math.pow(t1, Math.pow(t2, t1))).concat(Math.pow(t1, Math.pow(t2, t1)));
+"hello ".concat(t1 + Math.pow(t2, t1)).concat(t1 + Math.pow(t2, t1));
+"hello ".concat(Math.pow(t1, t2) + t1).concat(Math.pow(t1, t2) + t1);
+"hello ".concat(t1 + Math.pow(t2, t2) + t1).concat(t1 + Math.pow(t2, t2) + t1);
+"hello ".concat(typeof (Math.pow(t1, Math.pow(t2, t1)))).concat(typeof (Math.pow(t1, Math.pow(t2, t1))));
+"hello ".concat(Math.pow(t1, t2), " hello world ").concat(Math.pow(t1, t2));
+"hello ".concat(Math.pow(t1, Math.pow(t2, t1)), " hello world ").concat(Math.pow(t1, Math.pow(t2, t1)));
+"hello ".concat(t1 + Math.pow(t2, t1), " hello world ").concat(t1 + Math.pow(t2, t1));
+"hello ".concat(Math.pow(t1, t2) + t1, " hello world ").concat(Math.pow(t1, t2) + t1);
+"hello ".concat(t1 + Math.pow(t2, t2) + t1, " hello world ").concat(t1 + Math.pow(t2, t2) + t1);
+"hello ".concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " hello world ").concat(typeof (Math.pow(t1, Math.pow(t2, t1))));

tests/baselines/reference/emitExponentiationOperatorInTemplateString3.js

@@ -32,22 +32,22 @@ var t1 = 10;
 var t2 = 10;
 var s;
 // With TemplateTail
-Math.pow(t1, t2) + " world";
-Math.pow(t1, Math.pow(t2, t1)) + " world";
-t1 + Math.pow(t2, t1) + " world";
-Math.pow(t1, t2) + t1 + " world";
-t1 + Math.pow(t2, t2) + t1 + " world";
-typeof (Math.pow(t1, Math.pow(t2, t1))) + " world";
-1 + typeof (Math.pow(t1, Math.pow(t2, t1))) + " world";
-"" + Math.pow(t1, t2) + Math.pow(t1, t2) + " world";
-"" + Math.pow(t1, Math.pow(t2, t1)) + Math.pow(t1, Math.pow(t2, t1)) + " world";
-"" + (t1 + Math.pow(t2, t1)) + (t1 + Math.pow(t2, t1)) + " world";
-"" + (Math.pow(t1, t2) + t1) + (Math.pow(t1, t2) + t1) + " world";
-"" + (t1 + Math.pow(t2, t2) + t1) + (t1 + Math.pow(t2, t2) + t1) + " world";
-"" + typeof (Math.pow(t1, Math.pow(t2, t1))) + typeof (Math.pow(t1, Math.pow(t2, t1))) + " world";
-Math.pow(t1, t2) + " hello world " + Math.pow(t1, t2) + " !!";
-Math.pow(t1, Math.pow(t2, t1)) + " hello world " + Math.pow(t1, Math.pow(t2, t1)) + " !!";
-t1 + Math.pow(t2, t1) + " hello world " + (t1 + Math.pow(t2, t1)) + " !!";
-Math.pow(t1, t2) + t1 + " hello world " + (Math.pow(t1, t2) + t1) + " !!";
-t1 + Math.pow(t2, t2) + t1 + " hello world " + (t1 + Math.pow(t2, t2) + t1) + " !!";
-typeof (Math.pow(t1, Math.pow(t2, t1))) + " hello world " + typeof (Math.pow(t1, Math.pow(t2, t1))) + " !!";
+"".concat(Math.pow(t1, t2), " world");
+"".concat(Math.pow(t1, Math.pow(t2, t1)), " world");
+"".concat(t1 + Math.pow(t2, t1), " world");
+"".concat(Math.pow(t1, t2) + t1, " world");
+"".concat(t1 + Math.pow(t2, t2) + t1, " world");
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " world");
+"".concat(1 + typeof (Math.pow(t1, Math.pow(t2, t1))), " world");
+"".concat(Math.pow(t1, t2)).concat(Math.pow(t1, t2), " world");
+"".concat(Math.pow(t1, Math.pow(t2, t1))).concat(Math.pow(t1, Math.pow(t2, t1)), " world");
+"".concat(t1 + Math.pow(t2, t1)).concat(t1 + Math.pow(t2, t1), " world");
+"".concat(Math.pow(t1, t2) + t1).concat(Math.pow(t1, t2) + t1, " world");
+"".concat(t1 + Math.pow(t2, t2) + t1).concat(t1 + Math.pow(t2, t2) + t1, " world");
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1)))).concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " world");
+"".concat(Math.pow(t1, t2), " hello world ").concat(Math.pow(t1, t2), " !!");
+"".concat(Math.pow(t1, Math.pow(t2, t1)), " hello world ").concat(Math.pow(t1, Math.pow(t2, t1)), " !!");
+"".concat(t1 + Math.pow(t2, t1), " hello world ").concat(t1 + Math.pow(t2, t1), " !!");
+"".concat(Math.pow(t1, t2) + t1, " hello world ").concat(Math.pow(t1, t2) + t1, " !!");
+"".concat(t1 + Math.pow(t2, t2) + t1, " hello world ").concat(t1 + Math.pow(t2, t2) + t1, " !!");
+"".concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " hello world ").concat(typeof (Math.pow(t1, Math.pow(t2, t1))), " !!");

tests/baselines/reference/explainFilesNodeNextWithTypesReference.baseline.jsonc

@@ -0,0 +1,37 @@
+// === /node_modules/react-hook-form/dist/index.d.ts ===
+// /// <reference types="[|react|]/*FIND ALL REFS*/" />
+// export type Foo = React.Whatever;
+// export function useForm(): any;
+
+[
+  {
+    "definition": {
+      "containerKind": "",
+      "containerName": "",
+      "fileName": "/node_modules/react-hook-form/dist/index.d.ts",
+      "kind": "string",
+      "name": "react",
+      "textSpan": {
+        "start": 22,
+        "length": 5
+      },
+      "displayParts": [
+        {
+          "text": "\"react\"",
+          "kind": "stringLiteral"
+        }
+      ]
+    },
+    "references": [
+      {
+        "textSpan": {
+          "start": 22,
+          "length": 5
+        },
+        "fileName": "/node_modules/react-hook-form/dist/index.d.ts",
+        "isWriteAccess": false,
+        "isDefinition": false
+      }
+    ]
+  }
+]

tests/baselines/reference/exponentiationOperatorInTemplateStringWithSyntaxError1.js

@@ -32,21 +32,21 @@ var t2 = 10;
 var s;
 // Error: early syntax error using ES7 SimpleUnaryExpression on left-hand side without ()
 // TempateHead & TemplateTail are empty
-"" + (1 + Math.pow(typeof t1, Math.pow(t2, t1)));
-"" + (Math.pow(-t1, t2) - t1);
-"" + (Math.pow(-++t1, t2) - t1);
-"" + (Math.pow(-t1++, t2) - t1);
-"" + Math.pow(!t1, Math.pow(t2, --t1));
-"" + Math.pow(typeof t1, Math.pow(t2, t1));
-"" + (Math.pow(-t1, t2) - t1) + (Math.pow(-t1, t2) - t1);
-"" + (Math.pow(-++t1, t2) - t1) + (Math.pow(-++t1, t2) - t1);
-"" + (Math.pow(-t1++, t2) - t1) + (Math.pow(-t1++, t2) - t1);
-"" + Math.pow(!t1, Math.pow(t2, --t1)) + Math.pow(!t1, Math.pow(t2, --t1));
-"" + Math.pow(typeof t1, Math.pow(t2, t1)) + Math.pow(typeof t1, Math.pow(t2, t1));
-"" + (1 + Math.pow(typeof t1, Math.pow(t2, t1))) + (1 + Math.pow(typeof t1, Math.pow(t2, t1)));
-Math.pow(-t1, t2) - t1 + " hello world " + (Math.pow(-t1, t2) - t1);
-Math.pow(-++t1, t2) - t1 + " hello world " + (Math.pow(-++t1, t2) - t1);
-Math.pow(-t1++, t2) - t1 + " hello world " + (Math.pow(-t1++, t2) - t1);
-Math.pow(!t1, Math.pow(t2, --t1)) + " hello world " + Math.pow(!t1, Math.pow(t2, --t1));
-Math.pow(typeof t1, Math.pow(t2, t1)) + " hello world " + Math.pow(typeof t1, Math.pow(t2, t1));
-1 + Math.pow(typeof t1, Math.pow(t2, t1)) + " hello world " + (1 + Math.pow(typeof t1, Math.pow(t2, t1)));
+"".concat(1 + Math.pow(typeof t1, Math.pow(t2, t1)));
+"".concat(Math.pow(-t1, t2) - t1);
+"".concat(Math.pow(-++t1, t2) - t1);
+"".concat(Math.pow(-t1++, t2) - t1);
+"".concat(Math.pow(!t1, Math.pow(t2, --t1)));
+"".concat(Math.pow(typeof t1, Math.pow(t2, t1)));
+"".concat(Math.pow(-t1, t2) - t1).concat(Math.pow(-t1, t2) - t1);
+"".concat(Math.pow(-++t1, t2) - t1).concat(Math.pow(-++t1, t2) - t1);
+"".concat(Math.pow(-t1++, t2) - t1).concat(Math.pow(-t1++, t2) - t1);
+"".concat(Math.pow(!t1, Math.pow(t2, --t1))).concat(Math.pow(!t1, Math.pow(t2, --t1)));
+"".concat(Math.pow(typeof t1, Math.pow(t2, t1))).concat(Math.pow(typeof t1, Math.pow(t2, t1)));
+"".concat(1 + Math.pow(typeof t1, Math.pow(t2, t1))).concat(1 + Math.pow(typeof t1, Math.pow(t2, t1)));
+"".concat(Math.pow(-t1, t2) - t1, " hello world ").concat(Math.pow(-t1, t2) - t1);
+"".concat(Math.pow(-++t1, t2) - t1, " hello world ").concat(Math.pow(-++t1, t2) - t1);
+"".concat(Math.pow(-t1++, t2) - t1, " hello world ").concat(Math.pow(-t1++, t2) - t1);
+"".concat(Math.pow(!t1, Math.pow(t2, --t1)), " hello world ").concat(Math.pow(!t1, Math.pow(t2, --t1)));
+"".concat(Math.pow(typeof t1, Math.pow(t2, t1)), " hello world ").concat(Math.pow(typeof t1, Math.pow(t2, t1)));
+"".concat(1 + Math.pow(typeof t1, Math.pow(t2, t1)), " hello world ").concat(1 + Math.pow(typeof t1, Math.pow(t2, t1)));