Own delay implementation

Author: dex4er

package.json

@@ -41,8 +41,7 @@
     "tap-given": "^0.6.0",
     "tslint": "^5.10.0",
     "tslint-config-standard": "^7.1.0",
-    "typescript": "^2.9.2",
-    "util.promisify": "^1.0.0"
+    "typescript": "^2.9.2"
   },
   "scripts": {
     "pretest": "eslint . && tsc --noEmit --pretty && tslint -t stylish -p . && echo markdownlint *.md",

test/file-timestamp-stream.js

@@ -2,10 +2,6 @@
 
 process.env.TZ = 'GMT'
 
-const promisify = require('util.promisify')
-
-const delay = promisify(setTimeout)
-
 const FileTimestampStream = require('../lib/file-timestamp-stream').FileTimestampStream
 const mockFs = require('../mock/mock-fs')
 
@@ -15,6 +11,12 @@ require('tap-given')(t)
 const chai = require('chai')
 chai.should()
 
+function delay (ms) {
+  return new Promise((resolve) => {
+    setTimeout(resolve, ms)
+  })
+}
+
 Feature('Test file-timestamp-stream module', () => {
   Scenario('Write lines to different files', () => {
     let filename1