Repository: vercel/next.js
Pull request: fix: use .js extension for relative imports

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Changed files:
filename: packages/next/src/server/lib/router-utils/typegen.ts
patch: @@ -392,7 +392,9 @@ export function generateValidatorFile(
             : type
         return `// Validate ${filePath}
 {
-  const handler = {} as typeof import(${JSON.stringify(importPath)})
+  const handler = {} as typeof import(${JSON.stringify(
+    importPath.replace(/\.tsx?$/, '.js')
+  )})
   handler satisfies ${typeWithRoute}
 }`
       })
@@ -551,7 +553,7 @@ declare global {
     params: Promise<ParamMap[AppRoute]>
     searchParams: Promise<Record<string, string | string[] | undefined>>
   }
-  
+
   /**
    * Props for Next.js App Router layout components
    * @example

filename: test/e2e/app-dir/typed-routes-validator/typed-routes-validator.test.ts
patch: @@ -13,19 +13,19 @@ describe('typed-routes-validator', () => {
   it('should generate route validation correctly', async () => {
     const dts = await next.readFile('.next/types/validator.ts')
     expect(dts).toMatch(
-      /const handler = {} as typeof import\(".*\/app\/page.tsx"\)\s+handler satisfies AppPageConfig<"\/">/
+      /const handler = {} as typeof import\(".*\/app\/page.js"\)\s+handler satisfies AppPageConfig<"\/">/
     )
     expect(dts).toMatch(
-      /const handler = {} as typeof import\(".*\/app\/send-email\/route.ts"\)\s+handler satisfies RouteHandlerConfig<"\/send-email">/
+      /const handler = {} as typeof import\(".*\/app\/send-email\/route.js"\)\s+handler satisfies RouteHandlerConfig<"\/send-email">/
     )
     expect(dts).toMatch(
-      /const handler = {} as typeof import\(".*\/pages\/about.tsx"\)\s+handler satisfies PagesPageConfig/
+      /const handler = {} as typeof import\(".*\/pages\/about.js"\)\s+handler satisfies PagesPageConfig/
     )
     expect(dts).toMatch(
-      /const handler = {} as typeof import\(".*\/pages\/api\/test-route.ts"\)\s+handler satisfies ApiRouteConfig/
+      /const handler = {} as typeof import\(".*\/pages\/api\/test-route.js"\)\s+handler satisfies ApiRouteConfig/
     )
     expect(dts).toMatch(
-      /const handler = {} as typeof import\(".*\/app\/layout.tsx"\)\s+handler satisfies LayoutConfig<"\/">/
+      /const handler = {} as typeof import\(".*\/app\/layout.js"\)\s+handler satisfies LayoutConfig<"\/">/
     )
   })