Give more specific errors for verbatimModuleSyntax (#62113)

Author: DanielRosenwasser

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);
@@ -48325,7 +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 &&
@@ -48337,7 +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 (
@@ -48769,7 +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);
@@ -53334,7 +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

tests/baselines/reference/isolatedModulesShadowGlobalTypeNotValue(isolatedmodules=false,verbatimmodulesyntax=true).errors.txt

@@ -1,8 +1,8 @@
-bad.ts(1,10): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+bad.ts(1,10): error TS1295: 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.
 bad.ts(1,10): error TS1484: 'Date' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
-bad.ts(1,16): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+bad.ts(1,16): error TS1295: 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.
 bad.ts(1,16): error TS1484: 'Event' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
-good.ts(2,10): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+good.ts(2,10): error TS1295: 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.
 
 
 ==== ./types.ts (0 errors) ====
@@ -36,11 +36,11 @@ good.ts(2,10): error TS1286: ESM syntax is not allowed in a CommonJS module when
 ==== ./bad.ts (4 errors) ====
     import { Date, Event } from './types';
              ~~~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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.
              ~~~~
 !!! error TS1484: 'Date' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
                    ~~~~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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.
                    ~~~~~
 !!! error TS1484: 'Event' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
     function foo(a: Date) {
@@ -55,7 +55,7 @@ good.ts(2,10): error TS1286: ESM syntax is not allowed in a CommonJS module when
     import type { Date, Event } from './types';
     import { Console } from 'node:console';
              ~~~~~~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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 foo(a: Date) {
         const b = new Date(a.year, a.month, a.day);
         return b.getTime();

tests/baselines/reference/isolatedModulesShadowGlobalTypeNotValue(isolatedmodules=true,verbatimmodulesyntax=true).errors.txt

@@ -1,10 +1,10 @@
-bad.ts(1,10): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+bad.ts(1,10): error TS1295: 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.
 bad.ts(1,10): error TS1484: 'Date' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
 bad.ts(1,10): error TS2866: Import 'Date' conflicts with global value used in this file, so must be declared with a type-only import when 'isolatedModules' is enabled.
-bad.ts(1,16): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+bad.ts(1,16): error TS1295: 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.
 bad.ts(1,16): error TS1484: 'Event' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
 bad.ts(1,16): error TS2866: Import 'Event' conflicts with global value used in this file, so must be declared with a type-only import when 'isolatedModules' is enabled.
-good.ts(2,10): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+good.ts(2,10): error TS1295: 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.
 
 
 ==== ./types.ts (0 errors) ====
@@ -38,13 +38,13 @@ good.ts(2,10): error TS1286: ESM syntax is not allowed in a CommonJS module when
 ==== ./bad.ts (6 errors) ====
     import { Date, Event } from './types';
              ~~~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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.
              ~~~~
 !!! error TS1484: 'Date' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
              ~~~~
 !!! error TS2866: Import 'Date' conflicts with global value used in this file, so must be declared with a type-only import when 'isolatedModules' is enabled.
                    ~~~~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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.
                    ~~~~~
 !!! error TS1484: 'Event' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
                    ~~~~~
@@ -61,7 +61,7 @@ good.ts(2,10): error TS1286: ESM syntax is not allowed in a CommonJS module when
     import type { Date, Event } from './types';
     import { Console } from 'node:console';
              ~~~~~~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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 foo(a: Date) {
         const b = new Date(a.year, a.month, a.day);
         return b.getTime();

tests/baselines/reference/isolatedModulesSketchyAliasLocalMerge(isolatedmodules=false,verbatimmodulesyntax=true).errors.txt

@@ -1,4 +1,4 @@
-bad.ts(1,10): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+bad.ts(1,10): error TS1295: 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.
 bad.ts(1,10): error TS1484: 'FC' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
 
 
@@ -8,7 +8,7 @@ bad.ts(1,10): error TS1484: 'FC' is a type and must be imported using a type-onl
 ==== bad.ts (2 errors) ====
     import { FC } from "./types";
              ~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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.
              ~~
 !!! error TS1484: 'FC' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
     let FC: FC | null = null;

tests/baselines/reference/isolatedModulesSketchyAliasLocalMerge(isolatedmodules=true,verbatimmodulesyntax=true).errors.txt

@@ -1,4 +1,4 @@
-bad.ts(1,10): error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+bad.ts(1,10): error TS1295: 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.
 bad.ts(1,10): error TS1484: 'FC' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
 bad.ts(1,10): error TS2865: Import 'FC' conflicts with local value, so must be declared with a type-only import when 'isolatedModules' is enabled.
 
@@ -9,7 +9,7 @@ bad.ts(1,10): error TS2865: Import 'FC' conflicts with local value, so must be d
 ==== bad.ts (3 errors) ====
     import { FC } from "./types";
              ~~
-!!! error TS1286: ESM syntax is not allowed in a CommonJS module when 'verbatimModuleSyntax' is enabled.
+!!! error TS1295: 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.
              ~~
 !!! error TS1484: 'FC' is a type and must be imported using a type-only import when 'verbatimModuleSyntax' is enabled.
              ~~