test: improve child_process tests

Replaced var keyword with const and let in the tests for child process
stdin and stdio.

PR-URL: https://github.com/nodejs/node/pull/8617
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ilkka Myller <ilkka.myller@nodefield.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/test/parallel/test-child-process-stdio.js b/test/parallel/test-child-process-stdio.js
index 2daa748371..e24987ca64 100644
--- a/test/parallel/test-child-process-stdio.js
+++ b/test/parallel/test-child-process-stdio.js
@@ -1,9 +1,9 @@
 'use strict';
-var common = require('../common');
-var assert = require('assert');
+const common = require('../common');
+const assert = require('assert');
 
-var options = {stdio: ['pipe']};
-var child = common.spawnPwd(options);
+let options = {stdio: ['pipe']};
+let child = common.spawnPwd(options);
 
 assert.notEqual(child.stdout, null);
 assert.notEqual(child.stderr, null);