Support resolution-mode overrides in type-only constructs in all moduleResolution modes

src/compiler/checker.ts

@@ -39766,16 +39766,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         checkSourceElement(node.argument);
 
         if (node.attributes) {
-            const override = getResolutionModeOverride(node.attributes, grammarErrorOnNode);
-            const errorNode = node.attributes;
-            if (override && errorNode && getEmitModuleResolutionKind(compilerOptions) !== ModuleResolutionKind.Node16 && getEmitModuleResolutionKind(compilerOptions) !== ModuleResolutionKind.NodeNext) {
-                grammarErrorOnNode(
-                    errorNode,
-                    node.attributes.token === SyntaxKind.WithKeyword
-                        ? Diagnostics.The_resolution_mode_attribute_is_only_supported_when_moduleResolution_is_node16_or_nodenext
-                        : Diagnostics.resolution_mode_assertions_are_only_supported_when_moduleResolution_is_node16_or_nodenext,
-                );
-            }
+            getResolutionModeOverride(node.attributes, grammarErrorOnNode);
         }
         checkTypeReferenceOrImport(node);
     }
@@ -45212,14 +45203,6 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             const override = getResolutionModeOverride(node, validForTypeAttributes ? grammarErrorOnNode : undefined);
             const isImportAttributes = declaration.attributes.token === SyntaxKind.WithKeyword;
             if (validForTypeAttributes && override) {
-                if (getEmitModuleResolutionKind(compilerOptions) !== ModuleResolutionKind.Node16 && getEmitModuleResolutionKind(compilerOptions) !== ModuleResolutionKind.NodeNext) {
-                    return grammarErrorOnNode(
-                        node,
-                        isImportAttributes
-                            ? Diagnostics.The_resolution_mode_attribute_is_only_supported_when_moduleResolution_is_node16_or_nodenext
-                            : Diagnostics.resolution_mode_assertions_are_only_supported_when_moduleResolution_is_node16_or_nodenext,
-                    );
-                }
                 return; // Other grammar checks do not apply to type-only imports with resolution mode assertions
             }
 

src/compiler/diagnosticMessages.json

@@ -1480,10 +1480,6 @@
         "category": "Error",
         "code": 1451
     },
-    "'resolution-mode' assertions are only supported when `moduleResolution` is `node16` or `nodenext`.": {
-        "category": "Error",
-        "code": 1452
-    },
     "`resolution-mode` should be either `require` or `import`.": {
         "category": "Error",
         "code": 1453
@@ -1520,10 +1516,6 @@
         "category": "Message",
         "code": 1461
     },
-    "The 'resolution-mode' attribute is only supported when 'moduleResolution' is 'node16' or 'nodenext'.": {
-        "category": "Error",
-        "code": 1462
-    },
     "'resolution-mode' is the only valid key for type import attributes.": {
         "category": "Error",
         "code": 1463

src/compiler/program.ts

@@ -865,7 +865,6 @@ export function getModeForResolutionAtIndex(file: SourceFile, index: number): Re
 // eslint-disable-next-line @typescript-eslint/unified-signatures
 export function getModeForResolutionAtIndex(file: SourceFileImportsList, index: number): ResolutionMode;
 export function getModeForResolutionAtIndex(file: SourceFileImportsList, index: number): ResolutionMode {
-    if (file.impliedNodeFormat === undefined) return undefined;
     // we ensure all elements of file.imports and file.moduleAugmentations have the relevant parent pointers set during program setup,
     // so it's safe to use them even pre-bind
     return getModeForUsageLocation(file, getModuleNameStringLiteralAt(file, index));
@@ -892,7 +891,6 @@ export function isExclusivelyTypeOnlyImportOrExport(decl: ImportDeclaration | Ex
  * @returns The final resolution mode of the import
  */
 export function getModeForUsageLocation(file: { impliedNodeFormat?: ResolutionMode; }, usage: StringLiteralLike) {
-    if (file.impliedNodeFormat === undefined) return undefined;
     if ((isImportDeclaration(usage.parent) || isExportDeclaration(usage.parent))) {
         const isTypeOnly = isExclusivelyTypeOnlyImportOrExport(usage.parent);
         if (isTypeOnly) {
@@ -908,6 +906,7 @@ export function getModeForUsageLocation(file: { impliedNodeFormat?: ResolutionMo
             return override;
         }
     }
+    if (file.impliedNodeFormat === undefined) return undefined;
     if (file.impliedNodeFormat !== ModuleKind.ESNext) {
         // in cjs files, import call expressions are esm format, otherwise everything is cjs
         return isImportCall(walkUpParenthesizedExpressions(usage.parent)) ? ModuleKind.ESNext : ModuleKind.CommonJS;
@@ -3863,14 +3862,6 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
             const fileName = toFileNameLowerCase(ref.fileName);
             resolutionsInFile.set(fileName, getModeForFileReference(ref, file.impliedNodeFormat), resolvedTypeReferenceDirective);
             const mode = ref.resolutionMode || file.impliedNodeFormat;
-            if (mode && getEmitModuleResolutionKind(options) !== ModuleResolutionKind.Node16 && getEmitModuleResolutionKind(options) !== ModuleResolutionKind.NodeNext) {
-                (fileProcessingDiagnostics ??= []).push({
-                    kind: FilePreprocessingDiagnosticsKind.ResolutionDiagnostics,
-                    diagnostics: [
-                        createDiagnosticForRange(file, ref, Diagnostics.resolution_mode_assertions_are_only_supported_when_moduleResolution_is_node16_or_nodenext),
-                    ],
-                });
-            }
             processTypeReferenceDirective(fileName, mode, resolvedTypeReferenceDirective, { kind: FileIncludeKind.TypeReferenceDirective, file: file.path, index });
         }
     }

tests/baselines/reference/nodeModulesTripleSlashReferenceModeOverrideOldResolutionError.js

@@ -22,7 +22,7 @@ declare global {
 //// [index.ts]
 /// <reference types="pkg" resolution-mode="require" />
 /// <reference types="pkg" resolution-mode="import" />
-foo; // `resolution-mode` is an error in old resolution settings, which resolves is arbitrary
+foo;
 bar;
 export {};
 
@@ -31,5 +31,5 @@ export {};
 Object.defineProperty(exports, "__esModule", { value: true });
 /// <reference types="pkg" resolution-mode="require" />
 /// <reference types="pkg" resolution-mode="import" />
-foo; // `resolution-mode` is an error in old resolution settings, which resolves is arbitrary
+foo;
 bar;

tests/baselines/reference/nodeModulesTripleSlashReferenceModeOverrideOldResolutionError.symbols

@@ -1,9 +1,28 @@
 //// [tests/cases/conformance/node/nodeModulesTripleSlashReferenceModeOverrideOldResolutionError.ts] ////
 
 === /index.ts ===
-
 /// <reference types="pkg" resolution-mode="require" />
 /// <reference types="pkg" resolution-mode="import" />
-foo; // `resolution-mode` is an error in old resolution settings, which resolves is arbitrary
+foo;
+>foo : Symbol(foo, Decl(import.d.ts, 2, 7))
+
 bar;
+>bar : Symbol(bar, Decl(require.d.ts, 2, 7))
+
+export {};
+=== /node_modules/pkg/import.d.ts ===
 export {};
+declare global {
+>global : Symbol(global, Decl(import.d.ts, 0, 10))
+
+    var foo: number;
+>foo : Symbol(foo, Decl(import.d.ts, 2, 7))
+}
+=== /node_modules/pkg/require.d.ts ===
+export {};
+declare global {
+>global : Symbol(global, Decl(require.d.ts, 0, 10))
+
+    var bar: number;
+>bar : Symbol(bar, Decl(require.d.ts, 2, 7))
+}

tests/baselines/reference/nodeModulesTripleSlashReferenceModeOverrideOldResolutionError.types

@@ -3,10 +3,26 @@
 === /index.ts ===
 /// <reference types="pkg" resolution-mode="require" />
 /// <reference types="pkg" resolution-mode="import" />
-foo; // `resolution-mode` is an error in old resolution settings, which resolves is arbitrary
->foo : any
+foo;
+>foo : number
 
 bar;
->bar : any
+>bar : number
 
 export {};
+=== /node_modules/pkg/import.d.ts ===
+export {};
+declare global {
+>global : typeof global
+
+    var foo: number;
+>foo : number
+}
+=== /node_modules/pkg/require.d.ts ===
+export {};
+declare global {
+>global : typeof global
+
+    var bar: number;
+>bar : number
+}

tests/baselines/reference/resolutionModeImportType1(moduleresolution=bundler).symbols

@@ -0,0 +1,36 @@
+//// [tests/cases/conformance/moduleResolution/resolutionModeImportType1.ts] ////
+
+=== /node_modules/@types/foo/index.d.mts ===
+export declare const x: "module";
+>x : Symbol(x, Decl(index.d.mts, 0, 20))
+
+=== /node_modules/@types/foo/index.d.cts ===
+export declare const x: "script";
+>x : Symbol(x, Decl(index.d.cts, 0, 20))
+
+=== /app.ts ===
+type Default = typeof import("foo").x;
+>Default : Symbol(Default, Decl(app.ts, 0, 0))
+>x : Symbol(x, Decl(index.d.mts, 0, 20))
+
+type Import = typeof import("foo", { assert: { "resolution-mode": "import" } }).x;
+>Import : Symbol(Import, Decl(app.ts, 0, 38))
+>x : Symbol(x, Decl(index.d.mts, 0, 20))
+
+type Require = typeof import("foo", { assert: { "resolution-mode": "require" } }).x;
+>Require : Symbol(Require, Decl(app.ts, 1, 82))
+>x : Symbol(x, Decl(index.d.cts, 0, 20))
+
+// resolution-mode does not enforce file extension in `bundler`, just sets conditions
+type ImportRelative = typeof import("./other", { assert: { "resolution-mode": "import" } }).x;
+>ImportRelative : Symbol(ImportRelative, Decl(app.ts, 2, 84))
+>x : Symbol(x, Decl(other.ts, 0, 12))
+
+type RequireRelative = typeof import("./other", { assert: { "resolution-mode": "require" } }).x;
+>RequireRelative : Symbol(RequireRelative, Decl(app.ts, 4, 94))
+>x : Symbol(x, Decl(other.ts, 0, 12))
+
+=== /other.ts ===
+export const x = "other";
+>x : Symbol(x, Decl(other.ts, 0, 12))
+

tests/baselines/reference/resolutionModeImportType1(moduleresolution=bundler).types

@@ -0,0 +1,37 @@
+//// [tests/cases/conformance/moduleResolution/resolutionModeImportType1.ts] ////
+
+=== /node_modules/@types/foo/index.d.mts ===
+export declare const x: "module";
+>x : "module"
+
+=== /node_modules/@types/foo/index.d.cts ===
+export declare const x: "script";
+>x : "script"
+
+=== /app.ts ===
+type Default = typeof import("foo").x;
+>Default : "module"
+>x : error
+
+type Import = typeof import("foo", { assert: { "resolution-mode": "import" } }).x;
+>Import : "module"
+>x : error
+
+type Require = typeof import("foo", { assert: { "resolution-mode": "require" } }).x;
+>Require : "script"
+>x : error
+
+// resolution-mode does not enforce file extension in `bundler`, just sets conditions
+type ImportRelative = typeof import("./other", { assert: { "resolution-mode": "import" } }).x;
+>ImportRelative : "other"
+>x : error
+
+type RequireRelative = typeof import("./other", { assert: { "resolution-mode": "require" } }).x;
+>RequireRelative : "other"
+>x : error
+
+=== /other.ts ===
+export const x = "other";
+>x : "other"
+>"other" : "other"
+

tests/baselines/reference/resolutionModeImportType1(moduleresolution=classic).errors.txt

@@ -0,0 +1,46 @@
+error TS2688: Cannot find type definition file for 'foo'.
+  The file is in the program because:
+    Entry point for implicit type library 'foo'
+/app.ts(1,30): error TS2792: Cannot find module 'foo'. Did you mean to set the 'moduleResolution' option to 'nodenext', or to add aliases to the 'paths' option?
+/app.ts(2,29): error TS2792: Cannot find module 'foo'. Did you mean to set the 'moduleResolution' option to 'nodenext', or to add aliases to the 'paths' option?
+/app.ts(3,30): error TS2792: Cannot find module 'foo'. Did you mean to set the 'moduleResolution' option to 'nodenext', or to add aliases to the 'paths' option?
+
+
+!!! error TS2688: Cannot find type definition file for 'foo'.
+!!! error TS2688:   The file is in the program because:
+!!! error TS2688:     Entry point for implicit type library 'foo'
+==== /node_modules/@types/foo/package.json (0 errors) ====
+    {
+      "name": "@types/foo",
+      "version": "1.0.0",
+      "exports": {
+        ".": {
+          "import": "./index.d.mts",
+          "require": "./index.d.cts"
+        }
+      }
+    }
+
+==== /node_modules/@types/foo/index.d.mts (0 errors) ====
+    export declare const x: "module";
+
+==== /node_modules/@types/foo/index.d.cts (0 errors) ====
+    export declare const x: "script";
+
+==== /app.ts (3 errors) ====
+    type Default = typeof import("foo").x;
+                                 ~~~~~
+!!! error TS2792: Cannot find module 'foo'. Did you mean to set the 'moduleResolution' option to 'nodenext', or to add aliases to the 'paths' option?
+    type Import = typeof import("foo", { assert: { "resolution-mode": "import" } }).x;
+                                ~~~~~
+!!! error TS2792: Cannot find module 'foo'. Did you mean to set the 'moduleResolution' option to 'nodenext', or to add aliases to the 'paths' option?
+    type Require = typeof import("foo", { assert: { "resolution-mode": "require" } }).x;
+                                 ~~~~~
+!!! error TS2792: Cannot find module 'foo'. Did you mean to set the 'moduleResolution' option to 'nodenext', or to add aliases to the 'paths' option?
+    // resolution-mode does not enforce file extension in `bundler`, just sets conditions
+    type ImportRelative = typeof import("./other", { assert: { "resolution-mode": "import" } }).x;
+    type RequireRelative = typeof import("./other", { assert: { "resolution-mode": "require" } }).x;
+
+==== /other.ts (0 errors) ====
+    export const x = "other";
+

tests/baselines/reference/resolutionModeImportType1(moduleresolution=classic).symbols

@@ -0,0 +1,33 @@
+//// [tests/cases/conformance/moduleResolution/resolutionModeImportType1.ts] ////
+
+=== /node_modules/@types/foo/index.d.mts ===
+export declare const x: "module";
+>x : Symbol(x, Decl(index.d.mts, 0, 20))
+
+=== /node_modules/@types/foo/index.d.cts ===
+export declare const x: "script";
+>x : Symbol(x, Decl(index.d.cts, 0, 20))
+
+=== /app.ts ===
+type Default = typeof import("foo").x;
+>Default : Symbol(Default, Decl(app.ts, 0, 0))
+
+type Import = typeof import("foo", { assert: { "resolution-mode": "import" } }).x;
+>Import : Symbol(Import, Decl(app.ts, 0, 38))
+
+type Require = typeof import("foo", { assert: { "resolution-mode": "require" } }).x;
+>Require : Symbol(Require, Decl(app.ts, 1, 82))
+
+// resolution-mode does not enforce file extension in `bundler`, just sets conditions
+type ImportRelative = typeof import("./other", { assert: { "resolution-mode": "import" } }).x;
+>ImportRelative : Symbol(ImportRelative, Decl(app.ts, 2, 84))
+>x : Symbol(x, Decl(other.ts, 0, 12))
+
+type RequireRelative = typeof import("./other", { assert: { "resolution-mode": "require" } }).x;
+>RequireRelative : Symbol(RequireRelative, Decl(app.ts, 4, 94))
+>x : Symbol(x, Decl(other.ts, 0, 12))
+
+=== /other.ts ===
+export const x = "other";
+>x : Symbol(x, Decl(other.ts, 0, 12))
+