runTasksUntilStableAsync

Runs Angular change detection and processes tasks until the component fixture is stable using async/await.

This is the recommended default for new tests. It works with both zoneful and zoneless Angular applications and supports asynchronous response getters (Promises).

It does the following operations:

1. Runs change detection.
2. Responds to HTTP requests.
3. Waits for the fixture to become stable (via real time or a fake timer callback).
4. Runs the cycle again until both the fixture is stable and no HTTP requests remain.

Signature

await runTasksUntilStableAsync(
  fixture: ComponentFixture<unknown>,
  params?: RunTasksUntilStableAsyncParams
): Promise<void>

Parameters

fixture

The component fixture to stabilize.

params

Optional configuration object:

Property	Type	Default	Description
httpCallInstructions	HttpCallInstructionAsync[]	[]	Instructions for matching and responding to HTTP requests.
advanceTimers	(delayMs: number) => void | Promise<void>	—	Callback to advance fake timers during stabilization.
componentLongRunTimeout	number	10000	Timeout in ms after which a LongRunningComponentError is thrown.
debug	boolean	false	Logs warnings when setInterval is detected.

Throws

• LongRunningComponentError — when the component does not stabilize within componentLongRunTimeout.
• HttpInstructionWasNotExecutedDuringFixtureStabilizationError — when an instruction was never matched.
• NoMatchingHttpInstructionForRequestFoundError — when an HTTP request did not match any instruction.

Example

import {runTasksUntilStableAsync, predefinedHttpCallInstructionsAsync} from 'ngx-testbox/testing';

it('should load users', async () => {
  const fixture = TestBed.createComponent(UserListComponent);

  await runTasksUntilStableAsync(fixture, {
    httpCallInstructions: [
      predefinedHttpCallInstructionsAsync.get.success('/api/users', () => [
        {id: 1, name: 'Alice'},
      ]),
    ],
  });

  expect(fixture.componentInstance.users.length).toBe(1);
});

Using with fake timers

If your test uses fake timers, provide advanceTimers (example with Jasmine):

it('should handle debounced input', async () => {
  jasmine.clock().install();

  await runTasksUntilStableAsync(fixture, {
    httpCallInstructions: [searchSuccess],
    advanceTimers: (ms) => jasmine.clock().tick(ms),
  });

  jasmine.clock().uninstall();
});

Remarks

• This function processes only HTTP requests made using Angular HttpClient.
• Unlike runTasksUntilStable, this variant does not require fakeAsync and does not use tick().
• Response getters may return a Promise.
• The timeout default is 10 seconds. Increase componentLongRunTimeout for slow-loading components.

---

ResponseGetterAsync

The function that generates an HTTP response. May be synchronous or return a Promise.

type ResponseGetterAsync = (
  httpRequest: HttpRequest<unknown>,
  searchParams: URLSearchParams
) => Promise<HttpResponse<any>> | HttpResponse<any>;

HttpCallInstructionAsync

A tuple defining how to match and respond to an HTTP request in async mode:

type HttpCallInstructionAsync =
  | [HttpCallChecker, ResponseGetterAsync]
  | [HttpCallChecker, ResponseGetterAsync, HttpCallInstructionExtraParams];