Move shared test helpers into their own file

test/unit/helpers.js

@@ -0,0 +1,32 @@
+/**
+ * Copyright 2018 Google Inc. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {queueMicrotask, rIC} from '../../lib/utilities';
+
+
+export const when = async (fn, intervalMillis = 100, retries = 20) => {
+  for (let i = 0; i < retries; i++) {
+    const result = await fn();
+    if (result) {
+      return;
+    }
+    await new Promise((resolve) => setTimeout(resolve, intervalMillis));
+  }
+  throw new Error(`${fn} didn't return true after ${retries} retries.`);
+};
+
+export const nextMicroTask = () => new Promise((res) => queueMicrotask(res));
+export const nextIdleCallback = () => new Promise((res) => rIC(res));

test/unit/idle-queue-test.js

@@ -16,8 +16,10 @@
 
 
 import {dispatch} from 'dom-utils';
+import {nextMicroTask, nextIdleCallback, when} from './helpers';
 import IdleQueue from '../../lib/idle-queue';
-import {isSafari, queueMicrotask, rIC} from '../../lib/utilities';
+import {isSafari, rIC} from '../../lib/utilities';
+
 
 const sandbox = sinon.createSandbox();
 
@@ -49,20 +51,6 @@ const blockingSpy = (ms) => {
   });
 };
 
-const when = async (fn, intervalMillis = 100, retries = 20) => {
-  for (let i = 0; i < retries; i++) {
-    const result = await fn();
-    if (result) {
-      return;
-    }
-    await new Promise((resolve) => setTimeout(resolve, intervalMillis));
-  }
-  throw new Error(`${fn} didn't return true after ${retries} retries.`);
-};
-
-const nextMicroTask = () => new Promise((res) => queueMicrotask(res));
-const nextIdleCallback = () => new Promise((res) => rIC(res));
-
 describe('IdleQueue', () => {
   beforeEach(() => {
     sandbox.restore();