Fix stale dev types causing build failure after route deletion

gaojude · gaojude · commit b6673b4c7d72 · 2025-11-24T22:17:02.000-05:00
diff --git a/apps/bundle-analyzer/next-env.d.ts b/apps/bundle-analyzer/next-env.d.ts
@@ -1,6 +1,6 @@
 /// <reference types="next" />
 /// <reference types="next/image-types/global" />
-import './.next/types/routes.d.ts'
+import "./.next/types/routes.d.ts";
 
 // NOTE: This file should not be edited
 // see https://nextjs.org/docs/app/api-reference/config/typescript for more information.
diff --git a/packages/next/src/lib/typescript/runTypeCheck.ts b/packages/next/src/lib/typescript/runTypeCheck.ts
@@ -20,14 +20,25 @@ export async function runTypeCheck(
   distDir: string,
   tsConfigPath: string,
   cacheDir?: string,
-  isAppDirEnabled?: boolean
+  isAppDirEnabled?: boolean,
+  isolatedDevBuild?: boolean
 ): Promise<TypeCheckResult> {
   const effectiveConfiguration = await getTypeScriptConfiguration(
     typescript,
     tsConfigPath
   )
 
-  if (effectiveConfiguration.fileNames.length < 1) {
+  // When isolatedDevBuild is enabled, tsconfig includes both .next/types and
+  // .next/dev/types to avoid config churn between dev/build modes. During build,
+  // we filter out .next/dev/types files to prevent stale dev types from causing
+  // errors when routes have been deleted since the last dev session.
+  let fileNames = effectiveConfiguration.fileNames
+  if (isolatedDevBuild !== false) {
+    const devTypesPattern = /[/\\]\.next[/\\]dev[/\\]types[/\\]/
+    fileNames = fileNames.filter((fileName) => !devTypesPattern.test(fileName))
+  }
+
+  if (fileNames.length < 1) {
     return {
       hasWarnings: false,
       inputFilesCount: 0,
@@ -57,7 +68,7 @@ export async function runTypeCheck(
     }
     incremental = true
     program = typescript.createIncrementalProgram({
-      rootNames: effectiveConfiguration.fileNames,
+      rootNames: fileNames,
       options: {
         ...options,
         composite: false,
@@ -66,10 +77,7 @@ export async function runTypeCheck(
       },
     })
   } else {
-    program = typescript.createProgram(
-      effectiveConfiguration.fileNames,
-      options
-    )
+    program = typescript.createProgram(fileNames, options)
   }
 
   const result = program.emit()
@@ -147,7 +155,7 @@ export async function runTypeCheck(
   return {
     hasWarnings: true,
     warnings,
-    inputFilesCount: effectiveConfiguration.fileNames.length,
+    inputFilesCount: fileNames.length,
     totalFilesCount: program.getSourceFiles().length,
     incremental,
   }
diff --git a/packages/next/src/lib/verify-typescript-setup.ts b/packages/next/src/lib/verify-typescript-setup.ts
@@ -158,7 +158,8 @@ export async function verifyTypeScriptSetup({
         distDir,
         resolvedTsConfigPath,
         cacheDir,
-        hasAppDir
+        hasAppDir,
+        isolatedDevBuild
       )
     }
     return { result, version: typescriptVersion }
diff --git a/test/development/stale-dev-types/app/layout.tsx b/test/development/stale-dev-types/app/layout.tsx
@@ -0,0 +1,11 @@
+export default function RootLayout({
+  children,
+}: {
+  children: React.ReactNode
+}) {
+  return (
+    <html>
+      <body>{children}</body>
+    </html>
+  )
+}
diff --git a/test/development/stale-dev-types/app/page.tsx b/test/development/stale-dev-types/app/page.tsx
@@ -0,0 +1,3 @@
+export default function Page() {
+  return <div>Home Page</div>
+}
diff --git a/test/development/stale-dev-types/app/temp-route/page.tsx b/test/development/stale-dev-types/app/temp-route/page.tsx
@@ -0,0 +1,3 @@
+export default function TempPage() {
+  return <div>Temporary Page</div>
+}
diff --git a/test/development/stale-dev-types/next.config.js b/test/development/stale-dev-types/next.config.js
@@ -0,0 +1,6 @@
+/**
+ * @type {import('next').NextConfig}
+ */
+const nextConfig = {}
+
+module.exports = nextConfig
diff --git a/test/development/stale-dev-types/stale-dev-types.test.ts b/test/development/stale-dev-types/stale-dev-types.test.ts
@@ -0,0 +1,44 @@
+import { nextTestSetup } from 'e2e-utils'
+import { nextBuild } from 'next-test-utils'
+
+describe('stale-dev-types', () => {
+  const { next, skipped } = nextTestSetup({
+    files: __dirname,
+    skipDeployment: true,
+  })
+
+  if (skipped) {
+    return
+  }
+
+  it('should not fail build when .next/dev has stale types from deleted routes', async () => {
+    // Step 1: Ensure dev server has generated .next/dev/types/validator.ts
+    // The nextTestSetup in dev mode automatically starts the dev server
+    // Wait for types to be generated
+    await new Promise((resolve) => setTimeout(resolve, 3000))
+
+    // Verify .next/dev/types/validator.ts was generated with temp-route reference
+    const validatorTs = await next.readFile('.next/dev/types/validator.ts')
+    expect(validatorTs).toContain('/temp-route')
+
+    // Step 2: Stop the dev server
+    await next.stop()
+
+    // Step 3: Delete the route that was included in .next/dev/types/validator.ts
+    await next.deleteFile('app/temp-route/page.tsx')
+
+    // Step 4: Run build - it should NOT fail due to stale .next/dev types
+    // The bug is that build picks up .next/dev/types/validator.ts which references
+    // the deleted route, causing a type error
+    const result = await nextBuild(next.testDir, [], {
+      stdout: true,
+      stderr: true,
+    })
+
+    // Build should succeed - it should not type-check .next/dev
+    expect(result.stdout + result.stderr).not.toContain(
+      "Cannot find module '../../../app/temp-route/page"
+    )
+    expect(result.code).toBe(0)
+  })
+})

Original file line number	Diff line number	Diff line change
`@@ -158,7 +158,8 @@ export async function verifyTypeScriptSetup({`
`158`	`158`	`distDir,`
`159`	`159`	`resolvedTsConfigPath,`
`160`	`160`	`cacheDir,`
`161`		`- hasAppDir`
	`161`	`+ hasAppDir,`
	`162`	`+ isolatedDevBuild`
`162`	`163`	`)`
`163`	`164`	`}`
`164`	`165`	`return { result, version: typescriptVersion }`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+export default function Page() {`
	`2`	`+ return <div>Home Page</div>`
	`3`	`+}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+export default function TempPage() {`
	`2`	`+ return <div>Temporary Page</div>`
	`3`	`+}`