BranchSubscriber.test.js

import { NativeModules } from 'react-native'
const { RNBranch } = NativeModules
import { BranchSubscriber } from 'react-native-branch'

test('default initializes with no options', () => {
  const subscriber = new BranchSubscriber(null)
  expect(subscriber.options).toEqual({})
})

test('stores options passed to the constructor', () => {
  const subscriber = new BranchSubscriber({
    checkCachedEvents: false
  })

  expect(subscriber.options).toEqual({ checkCachedEvents: false })
})

test('subscribes to init session start events', () => {
  const subscriber = new BranchSubscriber({
    checkCachedEvents: false,
    onOpenStart: ({uri}) => {},
  })
  subscriber._nativeEventEmitter.addListener = jest.fn((eventType, listener) => {})
  subscriber.subscribe()

  expect(subscriber._nativeEventEmitter.addListener.mock.calls.length).toBe(1)
  expect(subscriber._nativeEventEmitter.addListener.mock.calls[0][0]).toBe(RNBranch.INIT_SESSION_START)
  expect(subscriber._nativeEventEmitter.addListener.mock.calls[0][1]).toBe(subscriber.options.onOpenStart)
})

test('subscribes to init session success & error events', () => {
  const subscriber = new BranchSubscriber({
    checkCachedEvents: false,
    onOpenComplete: ({params, error, uri}) => {},
  })
  subscriber._nativeEventEmitter.addListener = jest.fn((eventType, listener) => {})
  subscriber.subscribe()

  expect(subscriber._nativeEventEmitter.addListener.mock.calls.length).toBe(2)

  // This comparison ignores the call order.
  const mockArgs = subscriber._nativeEventEmitter.addListener.mock.calls.map(call => call[0]).sort()
  expect(mockArgs).toEqual([
    RNBranch.INIT_SESSION_ERROR,
    RNBranch.INIT_SESSION_SUCCESS,
  ])
  expect(subscriber._nativeEventEmitter.addListener.mock.calls[0][1]).toBe(subscriber.options.onOpenComplete)
  expect(subscriber._nativeEventEmitter.addListener.mock.calls[1][1]).toBe(subscriber.options.onOpenComplete)
})

// async test
test('will return a cached event when appropriate', done => {
  const mockResult = {
    params: {
      '+clicked_branch_link': false,
      '+is_first_session': false,
    },
    error: null,
    uri: null,
  }

  //* Mock promise from redeemInitSessionResult
  RNBranch.redeemInitSessionResult.mockReturnValueOnce(Promise.resolve(mockResult))
  // */

  // Set up subscriber, mocking the callbacks
  const subscriber = new BranchSubscriber({
    checkCachedEvents: true,
    onOpenStart: jest.fn(({uri}) => {}),
    onOpenComplete: jest.fn(({params, error, uri}) => {}),
  })

  // mock subscriber._nativeEventEmitter.addListener.

  // TODO: Brittle test
  // Expect first onOpenStart, then onOpenComplete, then _nativeEventEmitter.addListener three times,
  // with INIT_SESSION_ERROR last.
  subscriber._nativeEventEmitter.addListener = (eventType, listener) => {
    if (eventType !== RNBranch.INIT_SESSION_ERROR) return

    // --- Check results ---

    // Expect onOpenStart and onOpenComplete both to be called

    // uri passed to onOpenStart
    expect(subscriber.options.onOpenStart.mock.calls.length).toBe(1)
    expect(subscriber.options.onOpenStart.mock.calls[0][0]).toEqual({uri: null})

    // full result passed to onOpenComplete
    expect(subscriber.options.onOpenComplete.mock.calls.length).toBe(1)
    expect(subscriber.options.onOpenComplete.mock.calls[0][0]).toEqual(mockResult)

    // state cleared
    expect(subscriber._checkCachedEvents).toBe(false)

    done()
  }
  expect(subscriber._checkCachedEvents).toBe(true)

  // --- Code under test ---
  subscriber.subscribe()
})