@coriolis/coriolis/src/test/lib/rx/broadcastSubject.spec.js

Event sourced effect management

import { Subject } from 'rxjs'

import { createBroadcastSubject } from '../../../lib/rx/broadcastSubject'

describe('broadcastSubject', () => {
  it('Possible to add a target', () => {
    const results = []
    const { broadcastSubject, addTarget } = createBroadcastSubject()

    addTarget((value) => results.push(value))

    broadcastSubject.next('test')

    expect(results).to.deep.equal(['test'])
  })

  it('Broadcasts events to all targets', () => {
    const results1 = []
    const results2 = []
    const { broadcastSubject, addTarget } = createBroadcastSubject()

    addTarget((value) => results1.push(value))
    addTarget((value) => results2.push(value))

    broadcastSubject.next('testA')
    broadcastSubject.next('testB')

    expect(results1).to.deep.equal(['testA', 'testB'])
    expect(results2).to.deep.equal(['testA', 'testB'])
  })

  it('Possible to remove a target', () => {
    const results1 = []
    const results2 = []
    const results3 = []
    const { broadcastSubject, addTarget } = createBroadcastSubject()

    const removeTarget1 = addTarget((value) => results1.push(value))
    const removeTarget2 = addTarget((value) => results2.push(value))

    broadcastSubject.next('testA')

    const removeTarget3 = addTarget((value) => results3.push(value))

    broadcastSubject.next('testB')

    removeTarget2()

    broadcastSubject.next('testC')

    removeTarget3()

    broadcastSubject.next('testD')

    removeTarget1()

    broadcastSubject.next('testE')

    expect(results1).to.deep.equal(['testA', 'testB', 'testC', 'testD'])
    expect(results2).to.deep.equal(['testA', 'testB'])
    expect(results3).to.deep.equal(['testB', 'testC'])
  })

  it('A target can dispatch feedbacks', () => {
    const feedbacks = []
    const results = []

    const { broadcastSubject, addTarget } = createBroadcastSubject()

    // catch events emitted by targets (could be logging reports...)
    broadcastSubject.subscribe((value) => feedbacks.push(value))

    const feedbackSubject = new Subject()
    const targetInput = {
      next: (value) => {
        results.push(value)
        feedbackSubject.next('got it')
      },
    }
    const targetSubject = Subject.create(targetInput, feedbackSubject)

    const removeTarget1 = addTarget(targetSubject)

    broadcastSubject.next('testA')

    broadcastSubject.next('testB')

    removeTarget1()

    broadcastSubject.next('testC')

    expect(feedbacks).to.deep.equal(['got it', 'got it'])
    expect(results).to.deep.equal(['testA', 'testB'])
  })

  it('A target`s feedback error leads to error for all feedback observable')
})