add assertResources sanitizer to cli/js/ unit tests (#4161)

cli/js/workers_test.ts

@@ -1,23 +1,11 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
-import { test, testPerm, assert, assertEquals } from "./test_util.ts";
-
-export interface ResolvableMethods<T> {
-  resolve: (value?: T | PromiseLike<T>) => void;
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  reject: (reason?: any) => void;
-}
-
-export type Resolvable<T> = Promise<T> & ResolvableMethods<T>;
-
-export function createResolvable<T>(): Resolvable<T> {
-  let methods: ResolvableMethods<T>;
-  const promise = new Promise<T>((resolve, reject): void => {
-    methods = { resolve, reject };
-  });
-  // TypeScript doesn't know that the Promise callback occurs synchronously
-  // therefore use of not null assertion (`!`)
-  return Object.assign(promise, methods!) as Resolvable<T>;
-}
+import {
+  test,
+  testPerm,
+  assert,
+  assertEquals,
+  createResolvable
+} from "./test_util.ts";
 
 test(async function workersBasic(): Promise<void> {
   const promise = createResolvable();