fix: support process each out dir when there are two or more

packages/vite/src/node/build.ts

@@ -491,28 +491,30 @@ async function doBuild(
       libOptions,
       config.logger
     )
+    const normalizedOutputs: OutputOptions[] = []
+
+    if (Array.isArray(outputs)) {
+      for (const resolvedOutput of outputs) {
+        normalizedOutputs.push(buildOutputOptions(resolvedOutput))
+      }
+    } else {
+      normalizedOutputs.push(buildOutputOptions(outputs))
+    }
+
+    const outDirs = normalizedOutputs.map(({ dir }) => resolve(dir!))
 
     // watch file changes with rollup
     if (config.build.watch) {
       config.logger.info(colors.cyan(`\nwatching for file changes...`))
 
-      const output: OutputOptions[] = []
-      if (Array.isArray(outputs)) {
-        for (const resolvedOutput of outputs) {
-          output.push(buildOutputOptions(resolvedOutput))
-        }
-      } else {
-        output.push(buildOutputOptions(outputs))
-      }
-
       const resolvedChokidarOptions = resolveChokidarOptions(
         config.build.watch.chokidar
       )
 
       const { watch } = await import('rollup')
       const watcher = watch({
         ...rollupOptions,
-        output,
+        output: normalizedOutputs,
         watch: {
           ...config.build.watch,
           chokidar: resolvedChokidarOptions
@@ -523,7 +525,7 @@ async function doBuild(
         if (event.code === 'BUNDLE_START') {
           config.logger.info(colors.cyan(`\nbuild started...`))
           if (options.write) {
-            prepareOutDir(outDir, options.emptyOutDir, config)
+            prepareOutDir(outDirs, options.emptyOutDir, config)
           }
         } else if (event.code === 'BUNDLE_END') {
           event.result.close()
@@ -542,55 +544,65 @@ async function doBuild(
     parallelBuilds.push(bundle)
 
     const generate = (output: OutputOptions = {}) => {
-      return bundle[options.write ? 'write' : 'generate'](
-        buildOutputOptions(output)
-      )
+      return bundle[options.write ? 'write' : 'generate'](output)
     }
 
     if (options.write) {
-      prepareOutDir(outDir, options.emptyOutDir, config)
+      prepareOutDir(outDirs, options.emptyOutDir, config)
     }
 
-    if (Array.isArray(outputs)) {
-      const res = []
-      for (const output of outputs) {
-        res.push(await generate(output))
-      }
-      return res
-    } else {
-      return await generate(outputs)
+    const res = []
+    for (const output of normalizedOutputs) {
+      res.push(await generate(output))
     }
+    return Array.isArray(outputs) ? res : res[0]
   } catch (e) {
     outputBuildError(e)
     throw e
   }
 }
 
 function prepareOutDir(
-  outDir: string,
+  outDirs: string[],
   emptyOutDir: boolean | null,
   config: ResolvedConfig
 ) {
-  if (fs.existsSync(outDir)) {
-    if (
-      emptyOutDir == null &&
-      !normalizePath(outDir).startsWith(config.root + '/')
-    ) {
-      // warn if outDir is outside of root
-      config.logger.warn(
-        colors.yellow(
-          `\n${colors.bold(`(!)`)} outDir ${colors.white(
-            colors.dim(outDir)
-          )} is not inside project root and will not be emptied.\n` +
-            `Use --emptyOutDir to override.\n`
+  for (const outDir of outDirs) {
+    if (fs.existsSync(outDir)) {
+      if (
+        emptyOutDir == null &&
+        !normalizePath(outDir).startsWith(config.root + '/')
+      ) {
+        // warn if outDir is outside of root
+        config.logger.warn(
+          colors.yellow(
+            `\n${colors.bold(`(!)`)} outDir ${colors.white(
+              colors.dim(outDir)
+            )} is not inside project root and will not be emptied.\n` +
+              `Use --emptyOutDir to override.\n`
+          )
         )
-      )
-    } else if (emptyOutDir !== false) {
-      emptyDir(outDir, ['.git'])
+      } else if (emptyOutDir !== false) {
+        // skip those other outDirs which are nested in current outDir
+        const skipDirs = outDirs
+          .map((dir) => {
+            const relative = path.relative(outDir, dir)
+            if (
+              relative &&
+              !relative.startsWith('..') &&
+              !path.isAbsolute(relative)
+            ) {
+              return relative
+            }
+            return ''
+          })
+          .filter(Boolean)
+        emptyDir(outDir, [...skipDirs, '.git'])
+      }
+    }
+    if (config.publicDir && fs.existsSync(config.publicDir)) {
+      copyDir(config.publicDir, outDir)
     }
-  }
-  if (config.publicDir && fs.existsSync(config.publicDir)) {
-    copyDir(config.publicDir, outDir)
   }
 }
 

packages/vite/src/node/utils.ts

@@ -534,15 +534,35 @@ export function isFileReadable(filename: string): boolean {
 
 /**
  * Delete every file and subdirectory. **The given directory must exist.**
- * Pass an optional `skip` array to preserve files in the root directory.
+ * Pass an optional `skip` array to preserve files under the root directory.
  */
-export function emptyDir(dir: string, skip?: string[]): void {
+export function emptyDir(dir: string, skip: string[] = []): void {
+  let nested: Map<string, string[]> | null = null
+  skip = skip.map(slash)
   for (const file of fs.readdirSync(dir)) {
-    if (skip?.includes(file)) {
+    const matched = skip.find((f) => f === file || f.startsWith(`${file}/`))
+    if (matched) {
+      if (matched !== file) {
+        nested ??= new Map()
+        let nestedSkip = nested.get(`${dir}/${file}`)
+        if (!nestedSkip) {
+          nestedSkip = []
+          nested.set(`${dir}/${file}`, nestedSkip)
+        }
+        const skipPath = matched.replace(`${file}/`, '')
+        if (!nestedSkip.includes(skipPath)) {
+          nestedSkip.push(skipPath)
+        }
+      }
       continue
     }
     fs.rmSync(path.resolve(dir, file), { recursive: true, force: true })
   }
+  if (nested?.size) {
+    for (const [dir, nestedSkip] of nested) {
+      emptyDir(dir, nestedSkip)
+    }
+  }
 }
 
 export function copyDir(srcDir: string, destDir: string): void {