lib: tweak use of internal/errors

In addition refactor common.throws to common.expectsError

PR-URL: https://github.com/nodejs/node/pull/13829
Refs: https://github.com/nodejs/node/issues/11273
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

1 files changed, 15 insertions, 10 deletions

diff --git a/lib/internal/util.js b/lib/internal/util.js
index 735f78d4ac..e7b9b958c7 100644
--- a/lib/internal/util.js
+++ b/lib/internal/util.js
@@ -201,15 +201,17 @@ function getConstructorOf(obj) {
 const kCustomPromisifiedSymbol = Symbol('util.promisify.custom');
 const kCustomPromisifyArgsSymbol = Symbol('customPromisifyArgs');
 
-function promisify(orig) {
-  if (typeof orig !== 'function')
+function promisify(original) {
+  if (typeof original !== 'function')
     throw new errors.TypeError('ERR_INVALID_ARG_TYPE', 'original', 'function');
 
-  if (orig[kCustomPromisifiedSymbol]) {
-    const fn = orig[kCustomPromisifiedSymbol];
+  if (original[kCustomPromisifiedSymbol]) {
+    const fn = original[kCustomPromisifiedSymbol];
     if (typeof fn !== 'function') {
-      throw new TypeError('The [util.promisify.custom] property must be ' +
-                          'a function');
+      throw new errors.TypeError('ERR_INVALID_ARG_TYPE',
+                                 'util.promisify.custom',
+                                 'function',
+                                 fn);
     }
     Object.defineProperty(fn, kCustomPromisifiedSymbol, {
       value: fn, enumerable: false, writable: false, configurable: true
@@ -219,12 +221,12 @@ function promisify(orig) {
 
   // Names to create an object from in case the callback receives multiple
   // arguments, e.g. ['stdout', 'stderr'] for child_process.exec.
-  const argumentNames = orig[kCustomPromisifyArgsSymbol];
+  const argumentNames = original[kCustomPromisifyArgsSymbol];
 
   function fn(...args) {
     const promise = createPromise();
     try {
-      orig.call(this, ...args, (err, ...values) => {
+      original.call(this, ...args, (err, ...values) => {
         if (err) {
           promiseReject(promise, err);
         } else if (argumentNames !== undefined && values.length > 1) {
@@ -242,12 +244,15 @@ function promisify(orig) {
     return promise;
   }
 
-  Object.setPrototypeOf(fn, Object.getPrototypeOf(orig));
+  Object.setPrototypeOf(fn, Object.getPrototypeOf(original));
 
   Object.defineProperty(fn, kCustomPromisifiedSymbol, {
     value: fn, enumerable: false, writable: false, configurable: true
   });
-  return Object.defineProperties(fn, Object.getOwnPropertyDescriptors(orig));
+  return Object.defineProperties(
+    fn,
+    Object.getOwnPropertyDescriptors(original)
+  );
 }
 
 promisify.custom = kCustomPromisifiedSymbol;