Update error messages for CJS imports resolving to ES modules

src/compiler/checker.ts

@@ -3576,7 +3576,32 @@ 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 = currentSourceFile.packageJsonScope;
+                                    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_the_field_type_Colon_module_to_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_or_create_a_local_package_json_file_with_type_Colon_module,
+                                            targetExt));
+                                    }
+                                }
+                            }
                         }
                     }
                     // merged symbol is module declaration symbol combined with all augmentations

src/compiler/diagnosticMessages.json

@@ -1485,7 +1485,7 @@
         "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
     },
@@ -1517,6 +1517,18 @@
         "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}' or create a local package.json file with `{ \"type\": \"module\" }`.": {
+        "category": "Message",
+        "code": 1480
+    },
+    "To convert this file to an ECMAScript module, change its file extension to '{0}', or add the field `\"type\": \"module\"` to '{1}'.": {
+        "category": "Message",
+        "code": 1481
+    },
 
     "The types of '{0}' are incompatible between these types.": {
         "category": "Error",

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) ====
     {