The right way to check rxjs

Question

I brought the book rxjs in actionand just finished the testing section.

Testing rxjs codes is different from regular testing because everything is lazy loading.

In the book, they mention two testing methods: either passing (I use QUNIT, and the asynchronous signal code is complete) or marble diagrams.

My question is which method to choose, which I mentioned above?

Answer 1

. , , RxJs . , , RxJs5, .

RxJs5 RxJs4

RxJs4 5, , , , , TestScheduler . RxJs contributor kwonoj , RxJs5. npm npm install @kwonoj/rxjs-testscheduler-compat. TestScheduler , .startScheduler.

const TestScheduler = require('@kwonoj/rxjs-testscheduler-compat').TestScheduler;
const next = require('@kwonoj/rxjs-testscheduler-compat').next;
const complete = require('@kwonoj/rxjs-testscheduler-compat').complete;

it('works in RxJs5 with the compat package', () => {
  const scheduler = new TestScheduler(); // Note; no longer the Rx.TestScheduler

  const results = scheduler.startScheduler(
    () => Rx.Observable.interval(100, scheduler).take(3),
    { created: 100, subscribed: 200, unsubscribed: 1000 } // NOTE: disposed is now renamed to unsubscribed
  );

  collectionAssert.assertEqual(res.messages, [
    next(200 + 100, 0),
    next(200 + 200, 1),
    next(200 + 300, 2),
    complete(200 + 300)
  ]);
});

RxJs5 Marble

RxJs , , .

var e1 = hot('----a--^--b-------c--|');
var e2 = hot(  '---d-^--e---------f-----|');
var expected =      '---(be)----c-f-----|';

expectObservable(e1.merge(e2)).toBe(expected);

RxJs5. , , . codebase RxJs5, , , . RxJs5. .

Answer 2

, , , ( ) TestScheduler. , , . :

import { TestScheduler } from 'rxjs/testing';

const testScheduler = new TestScheduler((actual, expected) => {
  // asserting the two objects are equal
  // e.g. using chai.
  expect(actual).deep.equal(expected);
});

// This test will actually run *synchronously*
it('generate the stream correctly', () => {
  testScheduler.run(helpers => {
    const { cold, expectObservable, expectSubscriptions } = helpers;
    const e1 =  cold('-a--b--c---|');
    const subs =     '^----------!';
    const expected = '-a-----c---|';

    expectObservable(e1.pipe(throttleTime(3, testScheduler))).toBe(expected);
    expectSubscriptions(e1.subscriptions).toBe(subs);
  });
});

Jasmine, marbleTest() , s-ng-dev-utils:

import { marbleTest } from "s-ng-dev-utils";

it("generate the stream correctly", marbleTest(helpers => {
  const { cold, expectObservable, expectSubscriptions, testScheduler } = helpers;
  const e1 = cold(" -a--b--c---|");
  const subs = "    ^----------!";
  const expected = "-a-----c---|";

  expectObservable(e1.pipe(throttleTime(3, testScheduler))).toBe(expected);
  expectSubscriptions(e1.subscriptions).toBe(subs);
}));