autoRun.spec.ts

/* eslint-env jest */
import {filter, skip} from 'rxjs/operators';

import SubX from '../src/index';

describe('autoRun', () => {
  test('default', () => {
    const p = SubX.create({number: 1});
    let count = 0;
    SubX.autoRun(p, () => {
      count += 1;
      return p.number * 10;
    });
    p.number = 2;
    p.number = 3;
    p.number = 4;
    p.number = 5;
    expect(count).toBe(5);
  });

  test('stream', () => {
    const p = SubX.create({number: 1});
    const stream$ = SubX.autoRun(p, () => p.number * 10);
    const data: number[] = [];
    stream$.subscribe(i => data.push(i));
    p.number = 2;
    p.number = 3;
    p.number = 4;
    p.number = 5;
    expect(data).toEqual([10, 20, 30, 40, 50]);
  });

  test('stream complete', () => {
    const p = SubX.create({number: 1});
    let count = 0;
    const stream$ = SubX.autoRun(p, () => {
      count += 1;
      return p.number * 10;
    });
    const data: number[] = [];
    stream$.subscribe(i => data.push(i));
    p.number = 2;
    p.number = 3;
    stream$.complete();
    p.number = 4;
    p.number = 5;
    expect(count).toBe(3);
    expect(data).toEqual([10, 20, 30]);
  });

  test('operators', () => {
    const p = SubX.create({number: 1});
    let count = 0;
    const stream$ = SubX.autoRun(
      p,
      () => {
        count += 1;
        return p.number * 10;
      },
      filter(() => p.number % 2 === 1)
    );
    const data: number[] = [];
    stream$.subscribe(i => data.push(i));
    p.number = 2;
    p.number = 3;
    p.number = 4;
    p.number = 5;
    expect(count).toBe(3);
    expect(data).toEqual([10, 30, 50]);
  });

  test('operators 2', () => {
    const p = SubX.create({number: 1});
    let count = 0;
    const stream$ = SubX.autoRun(
      p,
      () => {
        count += 1;
        return p.number * 10;
      },
      filter(() => p.number % 2 === 0)
    );
    const data: number[] = [];
    stream$.subscribe(i => data.push(i));
    p.number = 2;
    p.number = 3;
    p.number = 4;
    p.number = 5;
    expect(count).toBe(3);
    expect(data).toEqual([10, 20, 40]); // operators doesn't affect first value
  });

  test('operators 3', () => {
    const p = SubX.create({number: 1});
    let count = 0;
    const stream$ = SubX.autoRun(
      p,
      () => {
        count += 1;
        return p.number * 10;
      },
      filter(() => p.number % 2 === 0)
    );
    const data: number[] = [];
    stream$.pipe(skip(1)).subscribe(i => data.push(i));
    p.number = 2;
    p.number = 3;
    p.number = 4;
    p.number = 5;
    expect(count).toBe(3);
    expect(data).toEqual([20, 40]); // we explicitly skip the first value
  });
});