Add native fs.copyFile to copy()

lib/copy/copy.js

@@ -75,7 +75,7 @@ function onFile (srcStat, src, dest, opts, cb) {
   checkDest(dest, (err, resolvedPath) => {
     if (err) return cb(err)
     if (resolvedPath === notExist) {
-      return cpFile(srcStat, src, dest, opts, cb)
+      return copyFile(srcStat, src, dest, opts, cb)
     } else if (resolvedPath === existsReg) {
       return mayCopyFile(srcStat, src, dest, opts, cb)
     } else {
@@ -89,30 +89,41 @@ function mayCopyFile (srcStat, src, dest, opts, cb) {
   if (opts.overwrite) {
     fs.unlink(dest, err => {
       if (err) return cb(err)
-      return cpFile(srcStat, src, dest, opts, cb)
+      return copyFile(srcStat, src, dest, opts, cb)
     })
   } else if (opts.errorOnExist) {
     return cb(new Error(`'${dest}' already exists`))
   } else return cb()
 }
 
-function cpFile (srcStat, src, dest, opts, cb) {
+function copyFile (srcStat, src, dest, opts, cb) {
+  if (typeof fs.copyFile === 'function') {
+    return fs.copyFile(src, dest, err => {
+      if (err) return cb(err)
+      return handleDestModeAndTimestamps(srcStat, dest, opts, cb)
+    })
+  }
+  return copyFileFallback(srcStat, src, dest, opts, cb)
+}
+
+function copyFileFallback (srcStat, src, dest, opts, cb) {
   const rs = fs.createReadStream(src)
   const ws = fs.createWriteStream(dest, { mode: srcStat.mode })
 
   rs.on('error', err => cb(err))
   ws.on('error', err => cb(err))
 
-  ws.on('open', () => {
-    rs.pipe(ws)
-  }).once('close', () => {
-    fs.chmod(dest, srcStat.mode, err => {
-      if (err) return cb(err)
-      if (opts.preserveTimestamps) {
-        return utimes(dest, srcStat.atime, srcStat.mtime, cb)
-      }
-      return cb()
-    })
+  ws.on('open', () => rs.pipe(ws))
+    .once('close', () => handleDestModeAndTimestamps(srcStat, dest, opts, cb))
+}
+
+function handleDestModeAndTimestamps (srcStat, dest, opts, cb) {
+  fs.chmod(dest, srcStat.mode, err => {
+    if (err) return cb(err)
+    if (opts.preserveTimestamps) {
+      return utimes(dest, srcStat.atime, srcStat.mtime, cb)
+    }
+    return cb()
   })
 }
 
@@ -131,7 +142,7 @@ function onDir (srcStat, src, dest, opts, cb) {
       return mayCopyDir(src, dest, opts, cb)
     } else {
       if (src === resolvedPath) return cb()
-      return cpDir(src, dest, opts, cb)
+      return copyDir(src, dest, opts, cb)
     }
   })
 }
@@ -142,7 +153,7 @@ function mayCopyDir (src, dest, opts, cb) {
     if (!st.isDirectory()) {
       return cb(new Error(`Cannot overwrite non-directory '${dest}' with directory '${src}'.`))
     }
-    return cpDir(src, dest, opts, cb)
+    return copyDir(src, dest, opts, cb)
   })
 }
 
@@ -151,24 +162,24 @@ function mkDirAndCopy (srcStat, src, dest, opts, cb) {
     if (err) return cb(err)
     fs.chmod(dest, srcStat.mode, err => {
       if (err) return cb(err)
-      return cpDir(src, dest, opts, cb)
+      return copyDir(src, dest, opts, cb)
     })
   })
 }
 
-function cpDir (src, dest, opts, cb) {
+function copyDir (src, dest, opts, cb) {
   fs.readdir(src, (err, items) => {
     if (err) return cb(err)
-    return cpDirItems(items, src, dest, opts, cb)
+    return copyDirItems(items, src, dest, opts, cb)
   })
 }
 
-function cpDirItems (items, src, dest, opts, cb) {
+function copyDirItems (items, src, dest, opts, cb) {
   const item = items.pop()
   if (!item) return cb()
   startCopy(path.join(src, item), path.join(dest, item), opts, err => {
     if (err) return cb(err)
-    return cpDirItems(items, src, dest, opts, cb)
+    return copyDirItems(items, src, dest, opts, cb)
   })
 }
 
@@ -201,27 +212,27 @@ function onLink (src, dest, opts, cb) {
           if (st.isDirectory() && isSrcSubdir(resolvedDestPath, resolvedSrcPath)) {
             return cb(new Error(`Cannot overwrite '${resolvedDestPath}' with '${resolvedSrcPath}'.`))
           }
-          return cpLink(resolvedSrcPath, dest, cb)
+          return copyLink(resolvedSrcPath, dest, cb)
         })
       }
     })
   })
 }
 
-function cpLink (resolvedSrcPath, dest, cb) {
+function copyLink (resolvedSrcPath, dest, cb) {
   fs.unlink(dest, err => {
     if (err) return cb(err)
     return fs.symlink(resolvedSrcPath, dest, cb)
   })
 }
 
-// check dest to see if it exists and/or is a symlink
+// check if dest exists and/or is a symlink
 function checkDest (dest, cb) {
   fs.readlink(dest, (err, resolvedPath) => {
     if (err) {
       if (err.code === 'ENOENT') return cb(null, notExist)
 
-      // dest exists and is a regular file or directory, Windows throws UNKNOWN error.
+      // dest exists and is a regular file or directory, Windows may throw UNKNOWN error.
       if (err.code === 'EINVAL' || err.code === 'UNKNOWN') return cb(null, existsReg)
 
       return cb(err)