Testing Utilities (`ngx-task/testing`)

Testing asynchronous code with timers, network calls, and cancellation usually requires complex fakeAsync, tick(), or flush logic.

ngx-task/testing provides testing utilities designed for clean unit and component tests.

import {
  createControlledTaskHandler,
  createTaskHarness,
  createDeferred,
  createTaskTestClock
} from 'ngx-task/testing';

---

1. createControlledTaskHandler()

Creates a handler function where you manually control when promises resolve or reject:

task.spec.ts

import { createTask } from 'ngx-task';
import { createControlledTaskHandler } from 'ngx-task/testing';

describe('Profile Task', () => {
  it('updates pending signal synchronously when controlled', async () => {
    const controlled = createControlledTaskHandler<string, { id: string }>();
    const task = createTask(controlled.handler, { injector: TestBed.inject(Injector) });

    expect(task.pending()).toBe(false);

    const execution = task.run('user-1');
    expect(task.pending()).toBe(true);

    // Resolve manually
    controlled.resolve({ id: 'user-1' });
    await execution.done;

    expect(task.pending()).toBe(false);
    expect(task.result()).toEqual({ id: 'user-1' });
  });
});

---

2. createTaskHarness()

Provides assertions and helper methods for testing Task instances in Angular component tests:

const harness = createTaskHarness(component.saveTask);

expect(harness.isIdle()).toBe(true);
component.clickSave();
expect(harness.isPending()).toBe(true);

---

3. Pure Test Primitives

• createDeferred<T>(): Creates a deferred object { promise, resolve, reject }.
• createTaskTestClock(): Virtual clock for testing pendingDelay and minimumPendingDuration without waiting real clock time.