feat(optimizer): show a friendly warning with 404 instead of 504 outdated optimize dep

packages/vite/src/node/plugins/optimizedDeps.ts

@@ -10,6 +10,8 @@ import { cleanUrl } from '../../shared/utils'
 export const ERR_OPTIMIZE_DEPS_PROCESSING_ERROR =
   'ERR_OPTIMIZE_DEPS_PROCESSING_ERROR'
 export const ERR_OUTDATED_OPTIMIZED_DEP = 'ERR_OUTDATED_OPTIMIZED_DEP'
+export const ERR_FILE_NOT_FOUND_IN_OPTIMIZED_DEP_DIR =
+  'ERR_FILE_NOT_FOUND_IN_OPTIMIZED_DEP_DIR'
 
 const debug = createDebugger('vite:optimize-deps')
 
@@ -68,8 +70,12 @@ export function optimizedDepsPlugin(config: ResolvedConfig): Plugin {
         try {
           return await fsp.readFile(file, 'utf-8')
         } catch (e) {
-          // Outdated non-entry points (CHUNK), loaded after a rerun
-          throwOutdatedRequest(id)
+          const newMetadata = depsOptimizer.metadata
+          if (optimizedDepInfoFromFile(newMetadata, file)) {
+            // Outdated non-entry points (CHUNK), loaded after a rerun
+            throwOutdatedRequest(id)
+          }
+          throwFileNotFoundInOptimizedDep(id)
         }
       }
     },
@@ -97,3 +103,15 @@ export function throwOutdatedRequest(id: string): never {
   // send a 504 status code request timeout
   throw err
 }
+
+export function throwFileNotFoundInOptimizedDep(id: string): never {
+  const err: any = new Error(
+    `The file does not exist at "${id}" which is in the optimize deps directory. ` +
+      `The dependency might be incompatible with the dep optimizer. ` +
+      `Try adding it to \`optimizeDeps.exclude\`.`,
+  )
+  err.code = ERR_FILE_NOT_FOUND_IN_OPTIMIZED_DEP_DIR
+  // This error will be caught by the transform middleware that will
+  // send a 404 status code not found
+  throw err
+}

packages/vite/src/node/server/middlewares/transform.ts

@@ -27,6 +27,7 @@ import {
   isDirectRequest,
 } from '../../plugins/css'
 import {
+  ERR_FILE_NOT_FOUND_IN_OPTIMIZED_DEP_DIR,
   ERR_OPTIMIZE_DEPS_PROCESSING_ERROR,
   ERR_OUTDATED_OPTIMIZED_DEP,
 } from '../../plugins/optimizedDeps'
@@ -253,6 +254,15 @@ export function transformMiddleware(
         // error but a normal part of the missing deps discovery flow
         return
       }
+      if (e?.code === ERR_FILE_NOT_FOUND_IN_OPTIMIZED_DEP_DIR) {
+        // Skip if response has already been sent
+        if (!res.writableEnded) {
+          res.statusCode = 404
+          res.end()
+        }
+        server.config.logger.warn(colors.yellow(e.message))
+        return
+      }
       if (e?.code === ERR_LOAD_URL) {
         // Let other middleware handle if we can't load the url via transformRequest
         return next()

playground/optimize-deps/__tests__/optimize-deps.spec.ts

@@ -319,3 +319,11 @@ test('long file name should work', async () => {
     `hello world`,
   )
 })
+
+test.runIf(isServe)('warn on incompatible dependency', () => {
+  expect(serverLogs).toContainEqual(
+    expect.stringContaining(
+      'The dependency might be incompatible with the dep optimizer.',
+    ),
+  )
+})

playground/optimize-deps/dep-incompatible/index.js

@@ -0,0 +1,3 @@
+const subUrl = new URL('./sub.js', import.meta.url)
+
+export default () => import(subUrl)

playground/optimize-deps/dep-incompatible/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "@vitejs/test-dep-incompatible",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "main": "index.js"
+}

playground/optimize-deps/dep-incompatible/sub.js

@@ -0,0 +1 @@
+export default 'sub'

playground/optimize-deps/index.html

@@ -263,3 +263,8 @@ <h2>Long file name import works</h2>
   text('.clonedeep-slash', cloneDeepSlash({ name: 'clonedeep-slash' }).name)
   text('.clonedeep-dot', cloneDeepDot({ name: 'clonedeep-dot' }).name)
 </script>
+
+<script type="module">
+  import loadSub from '@vitejs/test-dep-incompatible'
+  loadSub() // should show an error that tells there's an incompatible dep
+</script>

playground/optimize-deps/package.json

@@ -20,6 +20,7 @@
     "@vitejs/test-dep-cjs-with-assets": "file:./dep-cjs-with-assets",
     "@vitejs/test-dep-css-require": "file:./dep-css-require",
     "@vitejs/test-dep-esbuild-plugin-transform": "file:./dep-esbuild-plugin-transform",
+    "@vitejs/test-dep-incompatible": "file:./dep-incompatible",
     "@vitejs/test-dep-linked": "link:./dep-linked",
     "@vitejs/test-dep-linked-include": "link:./dep-linked-include",
     "@vitejs/test-dep-node-env": "file:./dep-node-env",