angular-docs-cn/modules/@angular/core/testing/fake_async.ts

90 lines
2.5 KiB
TypeScript

import {BaseException} from '../index';
import {getTestInjector} from './test_injector';
let _FakeAsyncTestZoneSpecType = Zone['FakeAsyncTestZoneSpec'];
/**
* Wraps a function to be executed in the fakeAsync zone:
* - microtasks are manually executed by calling `flushMicrotasks()`,
* - timers are synchronous, `tick()` simulates the asynchronous passage of time.
*
* If there are any pending timers at the end of the function, an exception will be thrown.
*
* Can be used to wrap inject() calls.
*
* ## Example
*
* {@example testing/ts/fake_async.ts region='basic'}
*
* @param fn
* @returns {Function} The function wrapped to be executed in the fakeAsync zone
*/
export function fakeAsync(fn: Function): Function {
if (Zone.current.get('FakeAsyncTestZoneSpec') != null) {
throw new BaseException('fakeAsync() calls can not be nested');
}
let fakeAsyncTestZoneSpec = new _FakeAsyncTestZoneSpecType();
let fakeAsyncZone = Zone.current.fork(fakeAsyncTestZoneSpec);
return function(...args) {
let res = fakeAsyncZone.run(() => {
let res = fn(...args);
flushMicrotasks();
return res;
});
if (fakeAsyncTestZoneSpec.pendingPeriodicTimers.length > 0) {
throw new BaseException(`${fakeAsyncTestZoneSpec.pendingPeriodicTimers.length} ` +
`periodic timer(s) still in the queue.`);
}
if (fakeAsyncTestZoneSpec.pendingTimers.length > 0) {
throw new BaseException(
`${fakeAsyncTestZoneSpec.pendingTimers.length} timer(s) still in the queue.`);
}
return res;
};
}
function _getFakeAsyncZoneSpec(): any {
let zoneSpec = Zone.current.get('FakeAsyncTestZoneSpec');
if (zoneSpec == null) {
throw new Error('The code should be running in the fakeAsync zone to call this function');
}
return zoneSpec;
}
/**
* Clear the queue of pending timers and microtasks.
* Tests no longer need to call this explicitly.
*
* @deprecated
*/
export function clearPendingTimers(): void {
// Do nothing.
}
/**
* Simulates the asynchronous passage of time for the timers in the fakeAsync zone.
*
* The microtasks queue is drained at the very start of this function and after any timer callback
* has been executed.
*
* ## Example
*
* {@example testing/ts/fake_async.ts region='basic'}
*
* @param {number} millis Number of millisecond, defaults to 0
*/
export function tick(millis: number = 0): void {
_getFakeAsyncZoneSpec().tick(millis);
}
/**
* Flush any pending microtasks.
*/
export function flushMicrotasks(): void {
_getFakeAsyncZoneSpec().flushMicrotasks();
}