bindActionCreators.spec.js

import { bindActionCreators, createStore } from '../'
import { todos } from './helpers/reducers'
import * as actionCreators from './helpers/actionCreators'

describe('bindActionCreators', () => {
  let store
  let actionCreatorFunctions

  beforeEach(() => {
    store = createStore(todos)
    actionCreatorFunctions = { ...actionCreators }
    Object.keys(actionCreatorFunctions).forEach(key => {
      if (typeof actionCreatorFunctions[key] !== 'function') {
        delete actionCreatorFunctions[key]
      }
    })
  })

  it('wraps the action creators with the dispatch function', () => {
    const boundActionCreators = bindActionCreators(actionCreators, store.dispatch)
    expect(
      Object.keys(boundActionCreators)
    ).toEqual(
      Object.keys(actionCreatorFunctions)
    )

    const action = boundActionCreators.addTodo('Hello')
    expect(action).toEqual(
      actionCreators.addTodo('Hello')
    )
    expect(store.getState()).toEqual([
      { id: 1, text: 'Hello' }
    ])
  })

  it('wraps action creators transparently', () => {
    const uniqueThis = {}
    const argArray = [1, 2, 3]
    function actionCreator() {
      return { type: 'UNKNOWN_ACTION', this: this, args: [...arguments] }
    }
    const boundActionCreator = bindActionCreators(actionCreator, store.dispatch)

    const boundAction = boundActionCreator.apply(uniqueThis,argArray)
    const action = actionCreator.apply(uniqueThis,argArray)
    expect(boundAction).toEqual(action)
    expect(boundAction.this).toBe(uniqueThis)
    expect(action.this).toBe(uniqueThis)
  })

  it('skips non-function values in the passed object', () => {
    const boundActionCreators = bindActionCreators({
      ...actionCreators,
      foo: 42,
      bar: 'baz',
      wow: undefined,
      much: {},
      test: null
    }, store.dispatch)
    expect(
      Object.keys(boundActionCreators)
    ).toEqual(
      Object.keys(actionCreatorFunctions)
    )
  })

  it('supports wrapping a single function only', () => {
    const actionCreator = actionCreators.addTodo
    const boundActionCreator = bindActionCreators(actionCreator, store.dispatch)

    const action = boundActionCreator('Hello')
    expect(action).toEqual(actionCreator('Hello'))
    expect(store.getState()).toEqual([
      { id: 1, text: 'Hello' }
    ])
  })

  it('throws for an undefined actionCreator', () => {
    expect(() => {
      bindActionCreators(undefined, store.dispatch)
    }).toThrow(
      'bindActionCreators expected an object or a function, instead received undefined. ' +
      'Did you write "import ActionCreators from" instead of "import * as ActionCreators from"?'
    )
  })

  it('throws for a null actionCreator', () => {
    expect(() => {
      bindActionCreators(null, store.dispatch)
    }).toThrow(
      'bindActionCreators expected an object or a function, instead received null. ' +
      'Did you write "import ActionCreators from" instead of "import * as ActionCreators from"?'
    )
  })

  it('throws for a primitive actionCreator', () => {
    expect(() => {
      bindActionCreators('string', store.dispatch)
    }).toThrow(
      'bindActionCreators expected an object or a function, instead received string. ' +
      'Did you write "import ActionCreators from" instead of "import * as ActionCreators from"?'
    )
  })
})