test: use arrow functions instead of bind

PR-URL: #17070 Reviewed-By: Michaël Zasso <targos@protonmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Lance Ball <lball@redhat.com> Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com> Reviewed-By: Khaidi Chu <i@2333.moe>

Author: tniessen

test/parallel/test-stream-push-strings.js

@@ -36,15 +36,15 @@ class MyStream extends Readable {
  case 0:
  return this.push(null);
  case 1:
- return setTimeout(function() {
+ return setTimeout(() => {
  this.push('last chunk');
- }.bind(this), 100);
+ }, 100);
  case 2:
  return this.push('second to last chunk');
  case 3:
- return process.nextTick(function() {
+ return process.nextTick(() => {
  this.push('first chunk');
- }.bind(this));
+ });
  default:
  throw new Error('?');
  }

test/parallel/test-stream2-transform.js

@@ -211,14 +211,14 @@ const Transform = require('_stream_transform');
  if (!chunk)
  chunk = '';
  const s = chunk.toString();
- setTimeout(function() {
+ setTimeout(() => {
  this.state += s.charAt(0);
  if (this.state.length === 3) {
  pt.push(Buffer.from(this.state));
  this.state = '';
  }
  cb();
- }.bind(this), 10);
+ }, 10);
  };
 
  pt._flush = function(cb) {