test: cleanup test-child-process-buffering.js

PR-URL: https://github.com/nodejs/node/pull/8578
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ilkka Myller <ilkka.myller@nodefield.com>

test/parallel/test-child-process-buffering.js

@@ -1,10 +1,10 @@
 'use strict';
-var common = require('../common');
+const common = require('../common');
-var assert = require('assert');
+const assert = require('assert');
 
 function pwd(callback) {
-  var output = '';
+  let output = '';
-  var child = common.spawnPwd();
+  const child = common.spawnPwd();
 
   child.stdout.setEncoding('utf8');
   child.stdout.on('data', function(s) {
@@ -14,7 +14,7 @@ function pwd(callback) {
 
   child.on('exit', common.mustCall(function(c) {
     console.log('exit: ' + c);
-    assert.equal(0, c);
+    assert.strictEqual(0, c);
   }));
 
   child.on('close', common.mustCall(function() {
@@ -25,6 +25,6 @@ function pwd(callback) {
 
 pwd(function(result) {
   console.dir(result);
-  assert.equal(true, result.length > 1);
+  assert.strictEqual(true, result.length > 1);
-  assert.equal('\n', result[result.length - 1]);
+  assert.strictEqual('\n', result[result.length - 1]);
 });