Update error messages for CJS imports resolving to ES modules

src/compiler/checker.ts

@@ -3581,7 +3581,32 @@ namespace ts {
                         // An override clause will take effect for type-only imports and import types, and allows importing the types across formats, regardless of
                         // normal mode restrictions
                         if (isSyncImport && sourceFile.impliedNodeFormat === ModuleKind.ESNext && !getResolutionModeOverrideForClause(overrideClause)) {
-                            error(errorNode, Diagnostics.Module_0_cannot_be_imported_using_this_construct_The_specifier_only_resolves_to_an_ES_module_which_cannot_be_imported_synchronously_Use_dynamic_import_instead, moduleReference);
+                            if (findAncestor(location, isImportEqualsDeclaration)) {
+                                // ImportEquals in a ESM file resolving to another ESM file
+                                error(errorNode, Diagnostics.Module_0_cannot_be_imported_using_this_construct_The_specifier_only_resolves_to_an_ES_module_which_cannot_be_imported_with_require_Use_an_ECMAScript_import_instead, moduleReference);
+                            }
+                            else {
+                                // CJS file resolving to an ESM file
+                                const diag = error(errorNode, Diagnostics.The_current_file_is_a_CommonJS_module_whose_imports_will_produce_require_calls_however_the_referenced_file_is_an_ECMAScript_module_and_cannot_be_imported_with_require_Consider_writing_a_dynamic_import_0_call_instead, moduleReference);
+                                const ext = tryGetExtensionFromPath(currentSourceFile.fileName);
+                                if (ext === Extension.Ts || ext === Extension.Js) {
+                                    const scope = host.getPackageScopeForPath(currentSourceFile.path);
+                                    const targetExt = ext === Extension.Ts ? Extension.Mts : Extension.Mjs;
+                                    if (scope && !scope.packageJsonContent.type) {
+                                        addRelatedInfo(diag, createDiagnosticForNode(
+                                            errorNode,
+                                            Diagnostics.To_convert_this_file_to_an_ECMAScript_module_change_its_file_extension_to_0_or_add_type_Colon_module_to_its_package_json_file_with_path_1,
+                                            targetExt,
+                                            combinePaths(scope.packageDirectory, "package.json")));
+                                    }
+                                    else {
+                                        addRelatedInfo(diag, createDiagnosticForNode(
+                                            errorNode,
+                                            Diagnostics.To_convert_this_file_to_an_ECMAScript_module_change_its_file_extension_to_0,
+                                            targetExt));
+                                    }
+                                }
+                            }
                         }
                     }
                     // merged symbol is module declaration symbol combined with all augmentations

src/compiler/diagnosticMessages.json

@@ -1469,7 +1469,7 @@
         "category": "Error",
         "code": 1470
     },
-    "Module '{0}' cannot be imported using this construct. The specifier only resolves to an ES module, which cannot be imported synchronously. Use dynamic import instead.": {
+    "Module '{0}' cannot be imported using this construct. The specifier only resolves to an ES module, which cannot be imported with 'require'. Use an ECMAScript import instead.": {
         "category": "Error",
         "code": 1471
     },
@@ -1501,6 +1501,18 @@
         "category": "Error",
         "code": 1478
     },
+    "The current file is a CommonJS module whose imports will produce 'require' calls; however, the referenced file is an ECMAScript module and cannot be imported with 'require'. Consider writing a dynamic 'import(\"{0}\")' call instead.": {
+        "category": "Error",
+        "code": 1479
+    },
+    "To convert this file to an ECMAScript module, change its file extension to '{0}'.": {
+        "category": "Message",
+        "code": 1480
+    },
+    "To convert this file to an ECMAScript module, change its file extension to '{0}', or add `\"type\": \"module\"` to its package.json file with path '{1}'.": {
+        "category": "Message",
+        "code": 1481
+    },
 
     "The types of '{0}' are incompatible between these types.": {
         "category": "Error",

src/compiler/moduleNameResolver.ts

@@ -1790,7 +1790,7 @@ namespace ts {
     }
 
     /*@internal*/
-    interface PackageJsonInfo {
+    export interface PackageJsonInfo {
         packageDirectory: string;
         packageJsonContent: PackageJsonPathFields;
         versionPaths: VersionPaths | undefined;

src/compiler/program.ts

@@ -1325,6 +1325,7 @@ namespace ts {
             directoryExists,
             getSymlinkCache,
             realpath: host.realpath?.bind(host),
+            getPackageScopeForPath: path => getPackageScopeForPath(path, moduleResolutionCache?.getPackageJsonInfoCache(), host, options),
             useCaseSensitiveFileNames: () => host.useCaseSensitiveFileNames(),
             getFileIncludeReasons: () => fileReasons,
             structureIsReused,

src/compiler/types.ts

@@ -4353,6 +4353,7 @@ namespace ts {
         getResolvedTypeReferenceDirectives(): ModeAwareCache<ResolvedTypeReferenceDirective | undefined>;
         getProjectReferenceRedirect(fileName: string): string | undefined;
         isSourceOfProjectReferenceRedirect(fileName: string): boolean;
+        getPackageScopeForPath(path: Path): PackageJsonInfo | undefined;
 
         readonly redirectTargetsMap: RedirectTargetsMap;
     }

src/server/editorServices.ts

@@ -4185,11 +4185,11 @@ namespace ts.server {
         }
 
         /*@internal*/
-        getPackageJsonsVisibleToFile(fileName: string, rootDir?: string): readonly PackageJsonInfo[] {
+        getPackageJsonsVisibleToFile(fileName: string, rootDir?: string): readonly ProjectPackageJsonInfo[] {
             const packageJsonCache = this.packageJsonCache;
             const rootPath = rootDir && this.toPath(rootDir);
             const filePath = this.toPath(fileName);
-            const result: PackageJsonInfo[] = [];
+            const result: ProjectPackageJsonInfo[] = [];
             const processDirectory = (directory: Path): boolean | undefined => {
                 switch (packageJsonCache.directoryHasPackageJson(directory)) {
                     // Sync and check same directory again

src/server/packageJsonCache.ts

@@ -2,16 +2,16 @@
 namespace ts.server {
     export interface PackageJsonCache {
         addOrUpdate(fileName: Path): void;
-        forEach(action: (info: PackageJsonInfo, fileName: Path) => void): void;
+        forEach(action: (info: ProjectPackageJsonInfo, fileName: Path) => void): void;
         delete(fileName: Path): void;
-        get(fileName: Path): PackageJsonInfo | false | undefined;
-        getInDirectory(directory: Path): PackageJsonInfo | undefined;
+        get(fileName: Path): ProjectPackageJsonInfo | false | undefined;
+        getInDirectory(directory: Path): ProjectPackageJsonInfo | undefined;
         directoryHasPackageJson(directory: Path): Ternary;
         searchDirectoryAndAncestors(directory: Path): void;
     }
 
     export function createPackageJsonCache(host: ProjectService): PackageJsonCache {
-        const packageJsons = new Map<string, PackageJsonInfo>();
+        const packageJsons = new Map<string, ProjectPackageJsonInfo>();
         const directoriesWithoutPackageJson = new Map<string, true>();
         return {
             addOrUpdate,

src/server/project.ts

@@ -1751,7 +1751,7 @@ namespace ts.server {
         }
 
         /*@internal*/
-        getPackageJsonsVisibleToFile(fileName: string, rootDir?: string): readonly PackageJsonInfo[] {
+        getPackageJsonsVisibleToFile(fileName: string, rootDir?: string): readonly ProjectPackageJsonInfo[] {
             if (this.projectService.serverMode !== LanguageServiceMode.Semantic) return emptyArray;
             return this.projectService.getPackageJsonsVisibleToFile(fileName, rootDir);
         }
@@ -1762,7 +1762,7 @@ namespace ts.server {
         }
 
         /*@internal*/
-        getPackageJsonsForAutoImport(rootDir?: string): readonly PackageJsonInfo[] {
+        getPackageJsonsForAutoImport(rootDir?: string): readonly ProjectPackageJsonInfo[] {
             const packageJsons = this.getPackageJsonsVisibleToFile(combinePaths(this.currentDirectory, inferredTypesContainingFile), rootDir);
             this.packageJsonsForAutoImport = new Set(packageJsons.map(p => p.fileName));
             return packageJsons;

src/services/types.ts

@@ -197,7 +197,7 @@ namespace ts {
     }
 
     /* @internal */
-    export interface PackageJsonInfo {
+    export interface ProjectPackageJsonInfo {
         fileName: string;
         parseable: boolean;
         dependencies?: ESMap<string, string>;
@@ -311,9 +311,9 @@ namespace ts {
 
         /* @internal */ getDocumentPositionMapper?(generatedFileName: string, sourceFileName?: string): DocumentPositionMapper | undefined;
         /* @internal */ getSourceFileLike?(fileName: string): SourceFileLike | undefined;
-        /* @internal */ getPackageJsonsVisibleToFile?(fileName: string, rootDir?: string): readonly PackageJsonInfo[];
+        /* @internal */ getPackageJsonsVisibleToFile?(fileName: string, rootDir?: string): readonly ProjectPackageJsonInfo[];
         /* @internal */ getNearestAncestorDirectoryWithPackageJson?(fileName: string): string | undefined;
-        /* @internal */ getPackageJsonsForAutoImport?(rootDir?: string): readonly PackageJsonInfo[];
+        /* @internal */ getPackageJsonsForAutoImport?(rootDir?: string): readonly ProjectPackageJsonInfo[];
         /* @internal */ getCachedExportInfoMap?(): ExportInfoMap;
         /* @internal */ getModuleSpecifierCache?(): ModuleSpecifierCache;
         /* @internal */ setCompilerHost?(host: CompilerHost): void;

src/services/utilities.ts

@@ -3004,12 +3004,12 @@ namespace ts {
         return packageJson;
     }
 
-    export function getPackageJsonsVisibleToFile(fileName: string, host: LanguageServiceHost): readonly PackageJsonInfo[] {
+    export function getPackageJsonsVisibleToFile(fileName: string, host: LanguageServiceHost): readonly ProjectPackageJsonInfo[] {
         if (!host.fileExists) {
             return [];
         }
 
-        const packageJsons: PackageJsonInfo[] = [];
+        const packageJsons: ProjectPackageJsonInfo[] = [];
         forEachAncestorDirectory(getDirectoryPath(fileName), ancestor => {
             const packageJsonFileName = combinePaths(ancestor, "package.json");
             if (host.fileExists(packageJsonFileName)) {
@@ -3023,7 +3023,7 @@ namespace ts {
         return packageJsons;
     }
 
-    export function createPackageJsonInfo(fileName: string, host: { readFile?(fileName: string): string | undefined }): PackageJsonInfo | undefined {
+    export function createPackageJsonInfo(fileName: string, host: { readFile?(fileName: string): string | undefined }): ProjectPackageJsonInfo | undefined {
         if (!host.readFile) {
             return undefined;
         }
@@ -3032,7 +3032,7 @@ namespace ts {
         const dependencyKeys = ["dependencies", "devDependencies", "optionalDependencies", "peerDependencies"] as const;
         const stringContent = host.readFile(fileName) || "";
         const content = tryParseJson(stringContent) as PackageJsonRaw | undefined;
-        const info: Pick<PackageJsonInfo, typeof dependencyKeys[number]> = {};
+        const info: Pick<ProjectPackageJsonInfo, typeof dependencyKeys[number]> = {};
         if (content) {
             for (const key of dependencyKeys) {
                 const dependencies = content[key];

tests/baselines/reference/nodeAllowJsPackageSelfName(module=node16).errors.txt

@@ -1,5 +1,5 @@
 error TS2209: The project root is ambiguous, but is required to resolve export map entry '.' in file 'tests/cases/conformance/node/allowJs/package.json'. Supply the `rootDir` compiler option to disambiguate.
-tests/cases/conformance/node/allowJs/index.cjs(2,23): error TS1471: Module 'package' cannot be imported using this construct. The specifier only resolves to an ES module, which cannot be imported synchronously. Use dynamic import instead.
+tests/cases/conformance/node/allowJs/index.cjs(2,23): error TS1479: The current file is a CommonJS module whose imports will produce 'require' calls; however, the referenced file is an ECMAScript module and cannot be imported with 'require'. Consider writing a dynamic 'import("package")' call instead.
 
 
 !!! error TS2209: The project root is ambiguous, but is required to resolve export map entry '.' in file 'tests/cases/conformance/node/allowJs/package.json'. Supply the `rootDir` compiler option to disambiguate.
@@ -15,7 +15,7 @@ tests/cases/conformance/node/allowJs/index.cjs(2,23): error TS1471: Module 'pack
     // esm format file
     import * as self from "package";
                           ~~~~~~~~~
-!!! error TS1471: Module 'package' cannot be imported using this construct. The specifier only resolves to an ES module, which cannot be imported synchronously. Use dynamic import instead.
+!!! error TS1479: The current file is a CommonJS module whose imports will produce 'require' calls; however, the referenced file is an ECMAScript module and cannot be imported with 'require'. Consider writing a dynamic 'import("package")' call instead.
     self;
 ==== tests/cases/conformance/node/allowJs/package.json (0 errors) ====
     {

tests/baselines/reference/nodeAllowJsPackageSelfName(module=nodenext).errors.txt

@@ -1,5 +1,5 @@
 error TS2209: The project root is ambiguous, but is required to resolve export map entry '.' in file 'tests/cases/conformance/node/allowJs/package.json'. Supply the `rootDir` compiler option to disambiguate.
-tests/cases/conformance/node/allowJs/index.cjs(2,23): error TS1471: Module 'package' cannot be imported using this construct. The specifier only resolves to an ES module, which cannot be imported synchronously. Use dynamic import instead.
+tests/cases/conformance/node/allowJs/index.cjs(2,23): error TS1479: The current file is a CommonJS module whose imports will produce 'require' calls; however, the referenced file is an ECMAScript module and cannot be imported with 'require'. Consider writing a dynamic 'import("package")' call instead.
 
 
 !!! error TS2209: The project root is ambiguous, but is required to resolve export map entry '.' in file 'tests/cases/conformance/node/allowJs/package.json'. Supply the `rootDir` compiler option to disambiguate.
@@ -15,7 +15,7 @@ tests/cases/conformance/node/allowJs/index.cjs(2,23): error TS1471: Module 'pack
     // esm format file
     import * as self from "package";
                           ~~~~~~~~~
-!!! error TS1471: Module 'package' cannot be imported using this construct. The specifier only resolves to an ES module, which cannot be imported synchronously. Use dynamic import instead.
+!!! error TS1479: The current file is a CommonJS module whose imports will produce 'require' calls; however, the referenced file is an ECMAScript module and cannot be imported with 'require'. Consider writing a dynamic 'import("package")' call instead.
     self;
 ==== tests/cases/conformance/node/allowJs/package.json (0 errors) ====
     {