Use fs.realpathSync.native if available (#5031)

* Pass in encoding to `realpath` call

Fixes #5030

* Use `fs.realpathSync.native` if it exists

* update changelog

CHANGELOG.md

@@ -16,6 +16,8 @@
   ([#4494](https://github.com/facebook/jest/pull/4494))
 * `[jest-cli]` Throw if `maxWorkers` doesn't have a value
   ([#4591](https://github.com/facebook/jest/pull/4591))
+* `[jest-cli]` Use `fs.realpathSync.native` if available
+  ([#5031](https://github.com/facebook/jest/pull/5031))
 * `[jest-config]` Fix `--passWithNoTests`
   ([#4639](https://github.com/facebook/jest/pull/4639))
 * `[jest-config]` Support `rootDir` tag in testEnvironment

packages/jest-cli/src/cli/index.js

@@ -15,6 +15,7 @@ import {
   Console,
   clearLine,
   createDirectory,
+  realpath,
   validateCLIOptions,
 } from 'jest-util';
 import {readConfig} from 'jest-config';
@@ -143,8 +144,7 @@ const getProjectListFromCLIArgs = (argv, project: ?Path) => {
 
   if (!projects.length && process.platform === 'win32') {
     try {
-      // $FlowFixMe
-      projects.push(process.binding('fs').realpath(process.cwd()));
+      projects.push(realpath(process.cwd()));
     } catch (err) {
       // do nothing, just catch error
       // process.binding('fs').realpath can throw, e.g. on mapped drives

packages/jest-runtime/src/script_transformer.js

@@ -17,7 +17,7 @@ import type {
 import crypto from 'crypto';
 import path from 'path';
 import vm from 'vm';
-import {createDirectory} from 'jest-util';
+import {createDirectory, realpath} from 'jest-util';
 import fs from 'graceful-fs';
 import {transform as babelTransform} from 'babel-core';
 import babelPluginIstanbul from 'babel-plugin-istanbul';
@@ -184,8 +184,7 @@ export default class ScriptTransformer {
 
   _getRealPath(filepath: Path): Path {
     try {
-      // $FlowFixMe
-      return process.binding('fs').realpath(filepath) || filepath;
+      return realpath(filepath) || filepath;
     } catch (err) {
       return filepath;
     }

packages/jest-util/src/index.js

@@ -8,6 +8,7 @@
  */
 
 import mkdirp from 'mkdirp';
+import fs from 'fs';
 
 import BufferedConsole from './buffered_console';
 import clearLine from './clear_line';
@@ -30,6 +31,15 @@ const createDirectory = (path: string) => {
   }
 };
 
+const realpath = (filepath: string) => {
+  if (typeof fs.realpathSync.native === 'function') {
+    return fs.realpathSync.native(filepath);
+  }
+
+  // $FlowFixMe: This is need for node@<9.2
+  return process.binding('fs').realpath(filepath, 'utf8');
+};
+
 module.exports = {
   BufferedConsole,
   Console,
@@ -40,6 +50,7 @@ module.exports = {
   formatTestResults,
   getConsoleOutput,
   installCommonGlobals,
+  realpath,
   setGlobal,
   validateCLIOptions,
 };