npm and error messages

node_modules/fs-extra/lib/copy-sync/copy-file-sync.js

@@ -0,0 +1,41 @@
+'use strict'
+
+const fs = require('graceful-fs')
+
+const BUF_LENGTH = 64 * 1024
+const _buff = require('../util/buffer')(BUF_LENGTH)
+
+function copyFileSync (srcFile, destFile, options) {
+  const overwrite = options.overwrite
+  const errorOnExist = options.errorOnExist
+  const preserveTimestamps = options.preserveTimestamps
+
+  if (fs.existsSync(destFile)) {
+    if (overwrite) {
+      fs.unlinkSync(destFile)
+    } else if (errorOnExist) {
+      throw new Error(`${destFile} already exists`)
+    } else return
+  }
+
+  const fdr = fs.openSync(srcFile, 'r')
+  const stat = fs.fstatSync(fdr)
+  const fdw = fs.openSync(destFile, 'w', stat.mode)
+  let bytesRead = 1
+  let pos = 0
+
+  while (bytesRead > 0) {
+    bytesRead = fs.readSync(fdr, _buff, 0, BUF_LENGTH, pos)
+    fs.writeSync(fdw, _buff, 0, bytesRead)
+    pos += bytesRead
+  }
+
+  if (preserveTimestamps) {
+    fs.futimesSync(fdw, stat.atime, stat.mtime)
+  }
+
+  fs.closeSync(fdr)
+  fs.closeSync(fdw)
+}
+
+module.exports = copyFileSync