perf(ui): improve get folder list to use Promises instead of sync

packages/@vue/cli-ui/apollo-server/connectors/folders.js

@@ -16,7 +16,7 @@ const cwd = require('./cwd')
 function isDirectory (file) {
   file = file.replace(/\\/g, path.sep)
   try {
-    return fs.statSync(file).isDirectory()
+    return fs.stat(file).then((x) => x.isDirectory())
   } catch (e) {
     if (process.env.VUE_APP_CLI_UI_DEBUG) console.warn(e.message)
   }
@@ -31,21 +31,41 @@ async function list (base, context) {
     }
   }
   const files = await fs.readdir(dir, 'utf8')
-  return files.map(
-    file => {
+
+  const f = await Promise.all(
+    files.map(async (file) => {
       const folderPath = path.join(base, file)
+
+      const [directory, hidden] = await Promise.all([
+        isDirectory(folderPath),
+        isHidden(folderPath)
+      ])
+      if (!directory) {
+        return null
+      }
       return {
         path: folderPath,
         name: file,
-        hidden: isHidden(folderPath)
+        hidden
       }
-    }
-  ).filter(
-    file => isDirectory(file.path)
+    })
   )
+  return f.filter((x) => !!x)
 }
 
-function isHidden (file) {
+async function isHiddenWindows (file) {
+  const windowsFile = file.replace(/\\/g, '\\\\')
+  return new Promise((resolve, reject) => {
+    winattr.get(windowsFile, (file, error) => {
+      if (error) {
+        return reject(error)
+      }
+      resolve(file)
+    })
+  }).then((x) => x.hidden)
+}
+
+async function isHidden (file) {
   try {
     const prefixed = path.basename(file).charAt(0) === hiddenPrefix
     const result = {
@@ -54,11 +74,13 @@ function isHidden (file) {
     }
 
     if (isPlatformWindows) {
-      const windowsFile = file.replace(/\\/g, '\\\\')
-      result.windows = winattr.getSync(windowsFile).hidden
+      result.windows = await isHiddenWindows(file)
     }
 
-    return (!isPlatformWindows && result.unix) || (isPlatformWindows && result.windows)
+    return (
+      (!isPlatformWindows && result.unix) ||
+      (isPlatformWindows && result.windows)
+    )
   } catch (e) {
     if (process.env.VUE_APP_CLI_UI_DEBUG) {
       console.log('file:', file)
@@ -142,9 +164,10 @@ function isVueProject (file, context) {
 }
 
 function listFavorite (context) {
-  return context.db.get('foldersFavorite').value().map(
-    file => generateFolder(file.id, context)
-  )
+  return context.db
+    .get('foldersFavorite')
+    .value()
+    .map((file) => generateFolder(file.id, context))
 }
 
 function isFavorite (file, context) {