Merge remote-tracking branch 'origin/main' into release-5.9

Author: typescript-bot

src/compiler/checker.ts

@@ -2528,6 +2528,20 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         return diagnostic;
     }
 
+    function getVerbatimModuleSyntaxErrorMessage(node: Node): DiagnosticMessage {
+        const sourceFile = getSourceFileOfNode(node);
+        const fileName = sourceFile.fileName;
+
+        // Check if the file is .cts or .cjs (CommonJS-specific extensions)
+        if (fileExtensionIsOneOf(fileName, [Extension.Cts, Extension.Cjs])) {
+            return Diagnostics.ECMAScript_imports_and_exports_cannot_be_written_in_a_CommonJS_file_under_verbatimModuleSyntax;
+        }
+        else {
+            // For .ts, .tsx, .js, etc.
+            return Diagnostics.ECMAScript_imports_and_exports_cannot_be_written_in_a_CommonJS_file_under_verbatimModuleSyntax_Adjust_the_type_field_in_the_nearest_package_json_to_make_this_file_an_ECMAScript_module_or_adjust_your_verbatimModuleSyntax_module_and_moduleResolution_settings_in_TypeScript;
+        }
+    }
+
     function addErrorOrSuggestion(isError: boolean, diagnostic: Diagnostic) {
         if (isError) {
             diagnostics.add(diagnostic);
@@ -6156,7 +6170,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         verbosityLevel?: number,
         out?: WriterContextOut,
     ): string {
-        const noTruncation = compilerOptions.noErrorTruncation ||
+        const noTruncation = !maximumLength && compilerOptions.noErrorTruncation ||
             flags & TypeFormatFlags.NoTruncation;
         const typeNode = nodeBuilder.typeToTypeNode(
             type,
@@ -32741,6 +32755,10 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
     function popContextualType() {
         contextualTypeCount--;
+        // Clear out the popped element's referenced objects.
+        contextualTypeNodes[contextualTypeCount] = undefined!;
+        contextualTypes[contextualTypeCount] = undefined;
+        contextualIsCache[contextualTypeCount] = undefined!;
     }
 
     function findContextualNode(node: Node, includeCaches: boolean) {
@@ -32760,6 +32778,8 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
     function popInferenceContext() {
         inferenceContextCount--;
+        inferenceContextNodes[inferenceContextCount] = undefined!;
+        inferenceContexts[inferenceContextCount] = undefined;
     }
 
     function getInferenceContext(node: Node) {
@@ -32772,12 +32792,15 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
     function pushActiveMapper(mapper: TypeMapper) {
         activeTypeMappers[activeTypeMappersCount] = mapper;
-        activeTypeMappersCaches[activeTypeMappersCount] = new Map();
+        activeTypeMappersCaches[activeTypeMappersCount] ??= new Map();
         activeTypeMappersCount++;
     }
 
     function popActiveMapper() {
         activeTypeMappersCount--;
+        // Clear out the popped element's referenced objects.
+        activeTypeMappers[activeTypeMappersCount] = undefined!;
+        activeTypeMappersCaches[activeTypeMappersCount].clear();
     }
 
     function findActiveMapper(mapper: TypeMapper) {
@@ -48316,7 +48339,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                     !isInJSFile(node) &&
                     host.getEmitModuleFormatOfFile(getSourceFileOfNode(node)) === ModuleKind.CommonJS
                 ) {
-                    error(node, Diagnostics.ESM_syntax_is_not_allowed_in_a_CommonJS_module_when_verbatimModuleSyntax_is_enabled);
+                    error(node, getVerbatimModuleSyntaxErrorMessage(node));
                 }
                 else if (
                     moduleKind === ModuleKind.Preserve &&
@@ -48328,7 +48351,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                     // when we look at the `impliedNodeFormat` of this file and decide it's CommonJS (i.e., currently,
                     // only if the file extension is .cjs/.cts). To avoid that inconsistency, we disallow ESM syntax
                     // in files that are unambiguously CommonJS in this mode.
-                    error(node, Diagnostics.ESM_syntax_is_not_allowed_in_a_CommonJS_module_when_module_is_set_to_preserve);
+                    error(node, Diagnostics.ECMAScript_module_syntax_is_not_allowed_in_a_CommonJS_module_when_module_is_set_to_preserve);
                 }
 
                 if (
@@ -48760,7 +48783,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         }
 
         if (isIllegalExportDefaultInCJS) {
-            error(node, Diagnostics.ESM_syntax_is_not_allowed_in_a_CommonJS_module_when_verbatimModuleSyntax_is_enabled);
+            error(node, getVerbatimModuleSyntaxErrorMessage(node));
         }
 
         checkExternalModuleExports(container);
@@ -53325,7 +53348,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
 
     function checkGrammarImportCallExpression(node: ImportCall): boolean {
         if (compilerOptions.verbatimModuleSyntax && moduleKind === ModuleKind.CommonJS) {
-            return grammarErrorOnNode(node, Diagnostics.ESM_syntax_is_not_allowed_in_a_CommonJS_module_when_verbatimModuleSyntax_is_enabled);
+            return grammarErrorOnNode(node, getVerbatimModuleSyntaxErrorMessage(node));
         }
 
         if (node.expression.kind === SyntaxKind.MetaProperty) {

src/compiler/diagnosticMessages.json

@@ -939,7 +939,7 @@
         "category": "Error",
         "code": 1285
     },
-    "ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.": {
+    "ECMAScript imports and exports cannot be written in a CommonJS file under 'verbatimModuleSyntax'.": {
         "category": "Error",
         "code": 1286
     },
@@ -967,14 +967,18 @@
         "category": "Error",
         "code": 1292
     },
-    "ESM syntax is not allowed in a CommonJS module when 'module' is set to 'preserve'.": {
+    "ECMAScript module syntax is not allowed in a CommonJS module when 'module' is set to 'preserve'.": {
         "category": "Error",
         "code": 1293
     },
     "This syntax is not allowed when 'erasableSyntaxOnly' is enabled.": {
         "category": "Error",
         "code": 1294
     },
+    "ECMAScript imports and exports cannot be written in a CommonJS file under 'verbatimModuleSyntax'. Adjust the 'type' field in the nearest 'package.json' to make this file an ECMAScript module, or adjust your 'verbatimModuleSyntax', 'module', and 'moduleResolution' settings in TypeScript.": {
+        "category": "Error",
+        "code": 1295
+    },
     "'with' statements are not allowed in an async function block.": {
         "category": "Error",
         "code": 1300