angular-docs-cn/packages/core/testing/src/async.ts

45 lines
1.3 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {asyncFallback} from './async_fallback';
/**
* Wraps a test function in an asynchronous test zone. The test will automatically
* complete when all asynchronous calls within this zone are done. Can be used
* to wrap an {@link inject} call.
*
* Example:
*
* ```
* it('...', async(inject([AClass], (object) => {
* object.doSomething.then(() => {
* expect(...);
* })
* });
* ```
*
* @publicApi
*/
export function async(fn: Function): (done: any) => any {
const _Zone: any = typeof Zone !== 'undefined' ? Zone : null;
if (!_Zone) {
return function() {
return Promise.reject(
'Zone is needed for the async() test helper but could not be found. ' +
'Please make sure that your environment includes zone.js/dist/zone.js');
};
}
const asyncTest = _Zone && _Zone[_Zone.__symbol__('asyncTest')];
if (typeof asyncTest === 'function') {
return asyncTest(fn);
}
// not using new version of zone.js
// TODO @JiaLiPassion, remove this after all library updated to
// newest version of zone.js(0.8.25)
return asyncFallback(fn);
}