angular-cn/packages/zone.js/lib/testing/fake-async.ts

154 lines
5.0 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 '../zone-spec/fake-async-test';
Zone.__load_patch('fakeasync', (global: any, Zone: ZoneType, api: _ZonePrivate) => {
const FakeAsyncTestZoneSpec = Zone && (Zone as any)['FakeAsyncTestZoneSpec'];
type ProxyZoneSpec = {
setDelegate(delegateSpec: ZoneSpec): void; getDelegate(): ZoneSpec; resetDelegate(): void;
};
const ProxyZoneSpec: {get(): ProxyZoneSpec; assertPresent: () => ProxyZoneSpec} =
Zone && (Zone as any)['ProxyZoneSpec'];
let _fakeAsyncTestZoneSpec: any = null;
/**
* Clears out the shared fake async zone for a test.
* To be called in a global `beforeEach`.
*
* @experimental
*/
function resetFakeAsyncZone() {
if (_fakeAsyncTestZoneSpec) {
_fakeAsyncTestZoneSpec.unlockDatePatch();
}
_fakeAsyncTestZoneSpec = null;
// in node.js testing we may not have ProxyZoneSpec in which case there is nothing to reset.
ProxyZoneSpec && ProxyZoneSpec.assertPresent().resetDelegate();
}
/**
* 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 core/testing/ts/fake_async.ts region='basic'}
*
* @param fn
* @returns The function wrapped to be executed in the fakeAsync zone
*
* @experimental
*/
function fakeAsync(fn: Function): (...args: any[]) => any {
// Not using an arrow function to preserve context passed from call site
return function(this: unknown, ...args: any[]) {
const proxyZoneSpec = ProxyZoneSpec.assertPresent();
if (Zone.current.get('FakeAsyncTestZoneSpec')) {
throw new Error('fakeAsync() calls can not be nested');
}
try {
// in case jasmine.clock init a fakeAsyncTestZoneSpec
if (!_fakeAsyncTestZoneSpec) {
if (proxyZoneSpec.getDelegate() instanceof FakeAsyncTestZoneSpec) {
throw new Error('fakeAsync() calls can not be nested');
}
_fakeAsyncTestZoneSpec = new FakeAsyncTestZoneSpec();
}
let res: any;
const lastProxyZoneSpec = proxyZoneSpec.getDelegate();
proxyZoneSpec.setDelegate(_fakeAsyncTestZoneSpec);
_fakeAsyncTestZoneSpec.lockDatePatch();
try {
res = fn.apply(this, args);
flushMicrotasks();
} finally {
proxyZoneSpec.setDelegate(lastProxyZoneSpec);
}
if (_fakeAsyncTestZoneSpec.pendingPeriodicTimers.length > 0) {
throw new Error(
`${_fakeAsyncTestZoneSpec.pendingPeriodicTimers.length} ` +
`periodic timer(s) still in the queue.`);
}
if (_fakeAsyncTestZoneSpec.pendingTimers.length > 0) {
throw new Error(
`${_fakeAsyncTestZoneSpec.pendingTimers.length} timer(s) still in the queue.`);
}
return res;
} finally {
resetFakeAsyncZone();
}
};
}
function _getFakeAsyncZoneSpec(): any {
if (_fakeAsyncTestZoneSpec == null) {
_fakeAsyncTestZoneSpec = Zone.current.get('FakeAsyncTestZoneSpec');
if (_fakeAsyncTestZoneSpec == null) {
throw new Error('The code should be running in the fakeAsync zone to call this function');
}
}
return _fakeAsyncTestZoneSpec;
}
/**
* 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 core/testing/ts/fake_async.ts region='basic'}
*
* @experimental
*/
function tick(millis: number = 0): void { _getFakeAsyncZoneSpec().tick(millis); }
/**
* Simulates the asynchronous passage of time for the timers in the fakeAsync zone by
* draining the macrotask queue until it is empty. The returned value is the milliseconds
* of time that would have been elapsed.
*
* @param maxTurns
* @returns The simulated time elapsed, in millis.
*
* @experimental
*/
function flush(maxTurns?: number): number { return _getFakeAsyncZoneSpec().flush(maxTurns); }
/**
* Discard all remaining periodic tasks.
*
* @experimental
*/
function discardPeriodicTasks(): void {
const zoneSpec = _getFakeAsyncZoneSpec();
const pendingTimers = zoneSpec.pendingPeriodicTimers;
zoneSpec.pendingPeriodicTimers.length = 0;
}
/**
* Flush any pending microtasks.
*
* @experimental
*/
function flushMicrotasks(): void { _getFakeAsyncZoneSpec().flushMicrotasks(); }
(Zone as any)[api.symbol('fakeAsyncTest')] = {
resetFakeAsyncZone, flushMicrotasks, discardPeriodicTasks, tick, flush, fakeAsync};
});