fix(deps): watch asset files in linked optimized dependencies

packages/vite/src/node/optimizer/index.ts

@@ -272,6 +272,10 @@ export interface DepOptimizationMetadata {
    * OptimizedDepInfo list
    */
   depInfoList: OptimizedDepInfo[]
+  /**
+   * Directories and files to watch for changes
+   */
+  watchFiles?: string[]
 }
 
 /**
@@ -728,6 +732,29 @@ export function runOptimizeDeps(
           }
         }
 
+        // Gather directories of linked monorepo packages to watch for changes
+        metadata.watchFiles ??= []
+        for (const depInfo of Object.values(metadata.optimized)) {
+          if (depInfo.src) {
+            try {
+              const realPath = fs.realpathSync(depInfo.src)
+              if (!realPath.includes('node_modules')) {
+                const pkgPath = lookupFile(path.dirname(realPath), [
+                  'package.json',
+                ])
+                if (pkgPath) {
+                  const pkgDir = path.dirname(pkgPath)
+                  if (!metadata.watchFiles.includes(pkgDir)) {
+                    metadata.watchFiles.push(pkgDir)
+                  }
+                }
+              }
+            } catch (_e) {
+              // Ignore
+            }
+          }
+        }
+
         clearTimeout(bundleTimer)
 
         debug?.(
@@ -1014,15 +1041,22 @@ function parseDepsOptimizerMetadata(
   jsonMetadata: string,
   depsCacheDir: string,
 ): DepOptimizationMetadata | undefined {
-  const { hash, lockfileHash, configHash, browserHash, optimized, chunks } =
-    JSON.parse(jsonMetadata, (key: string, value: string) => {
-      // Paths can be absolute or relative to the deps cache dir where
-      // the _metadata.json is located
-      if (key === 'file' || key === 'src') {
-        return normalizePath(path.resolve(depsCacheDir, value))
-      }
-      return value
-    })
+  const {
+    hash,
+    lockfileHash,
+    configHash,
+    browserHash,
+    optimized,
+    chunks,
+    watchFiles,
+  } = JSON.parse(jsonMetadata, (key: string, value: string) => {
+    // Paths can be absolute or relative to the deps cache dir where
+    // the _metadata.json is located
+    if (key === 'file' || key === 'src') {
+      return normalizePath(path.resolve(depsCacheDir, value))
+    }
+    return value
+  })
   if (
     !chunks ||
     Object.values(optimized).some((depInfo: any) => !depInfo.fileHash)
@@ -1039,6 +1073,7 @@ function parseDepsOptimizerMetadata(
     discovered: {},
     chunks: {},
     depInfoList: [],
+    watchFiles: watchFiles || [],
   }
   for (const id of Object.keys(optimized)) {
     addOptimizedDepInfo(metadata, 'optimized', {
@@ -1068,14 +1103,22 @@ function stringifyDepsOptimizerMetadata(
   metadata: DepOptimizationMetadata,
   depsCacheDir: string,
 ) {
-  const { hash, configHash, lockfileHash, browserHash, optimized, chunks } =
-    metadata
+  const {
+    hash,
+    configHash,
+    lockfileHash,
+    browserHash,
+    optimized,
+    chunks,
+    watchFiles,
+  } = metadata
   return JSON.stringify(
     {
       hash,
       configHash,
       lockfileHash,
       browserHash,
+      watchFiles,
       optimized: Object.fromEntries(
         Object.values(optimized).map(
           ({ id, src, file, fileHash, needsInterop, isDynamicEntry }) => [

packages/vite/src/node/server/environment.ts

@@ -271,6 +271,11 @@ export class DevEnvironment extends BaseEnvironment {
   async listen(server: ViteDevServer): Promise<void> {
     this.hot.listen()
     await Promise.all([this.bundledDev?.listen(), this.depsOptimizer?.init()])
+
+    if (this.depsOptimizer?.metadata.watchFiles) {
+      server.watcher.add(this.depsOptimizer.metadata.watchFiles)
+    }
+
     warmupFiles(server, this)
   }
 

packages/vite/src/node/server/index.ts

@@ -903,8 +903,34 @@ export async function _createServer(
     }
   }
 
+  const checkOptimizedDepSource = async (file: string) => {
+    let isOptimizedDepSource = false
+    for (const environment of Object.values(server.environments)) {
+      if (
+        environment.depsOptimizer?.metadata.watchFiles?.some(
+          (id) => file === id || file.startsWith(id + '/'),
+        )
+      ) {
+        isOptimizedDepSource = true
+        break
+      }
+    }
+    if (isOptimizedDepSource) {
+      server.config.logger.info(
+        colors.green(
+          `optimized dependency source changed, restarting server...`,
+        ),
+        { clear: true, timestamp: true },
+      )
+      await server.restart(true)
+      return true
+    }
+    return false
+  }
+
   const onFileAddUnlink = async (file: string, isUnlink: boolean) => {
     file = normalizePath(file)
+    if (await checkOptimizedDepSource(file)) return
     reloadOnTsconfigChange(server, file)
 
     await Promise.all(
@@ -943,6 +969,7 @@ export async function _createServer(
 
   const onFileChange = async (file: string) => {
     file = normalizePath(file)
+    if (await checkOptimizedDepSource(file)) return
     reloadOnTsconfigChange(server, file)
 
     await Promise.all(