fix: requested changes

Author: kalvenschraut

packages/vue-language-core/src/languageModule.ts

@@ -52,6 +52,8 @@ export function createLanguage(
 		vueCompilerOptions,
 		codegenStack,
 	);
+	patchResolveModuleNames(ts, vueCompilerOptions);
+
 	const sharedTypesSnapshot = ts.ScriptSnapshot.fromString(sharedTypes.getTypesCode(vueCompilerOptions));
 	const languageModule: Language = {
 		createVirtualFile(fileName, snapshot, languageId) {
@@ -108,7 +110,7 @@ export function createLanguage(
 				) {
 					return moduleLiterals.map((moduleLiteral) => {
 						let moduleName = moduleLiteral.text;
-						if (sourceFile.impliedNodeFormat === ts.ModuleKind.ESNext && moduleName.endsWith('.vue')) {
+						if (sourceFile.impliedNodeFormat === ts.ModuleKind.ESNext && vueCompilerOptions.extensions.some(ext => moduleName.endsWith(ext))) {
 							moduleName = `${moduleName}.js`;
 						}
 						return ts.resolveModuleName(
@@ -146,3 +148,25 @@ export function createLanguages(
 		...vueCompilerOptions.experimentalAdditionalLanguageModules?.map(module => require(module)) ?? [],
 	];
 }
+
+function patchResolveModuleNames(
+	ts: typeof import('typescript/lib/tsserverlibrary'),
+	vueCompilerOptions: VueCompilerOptions,
+) {
+	try {
+		// from https://github.com/vuejs/language-tools/pull/1543
+		if (!((ts as any).__vuePatchResolveModuleNames)) {
+			(ts as any).__vuePatchResolveModuleNames = true;
+			const resolveModuleNames = ts.resolveModuleName;
+			ts.resolveModuleName = (...args) => {
+				if (args[6] === ts.ModuleKind.ESNext && vueCompilerOptions.extensions.some(ext => args[0].endsWith(ext))) {
+					args[6] = ts.ModuleKind.CommonJS;
+				}
+				return resolveModuleNames(...args);
+			};
+		}
+	}
+	catch (e) {
+		// console.warn('[volar] patchResolveModuleNames failed', e);
+	}
+}