test helper for promise and vuex

test_helper.js

// TEST PROMISE OBJECT TO BE FULFILLED OR REJECTED
// ---
// describe('promise', () => {
//   it('should be fulfilled', () => {
//     return shouldFulfilled(promise()).then((value) => {
//       expect(velue).to.be.true
//     })
//   })
// })
//
// describe('promise', () => {
//   it('should be rejected', () => {
//     return shouldRejected(promise()).catch((error) => {
//       expect(error).have.property('message')
//       .and.equal('error')
//     })
//   })
// })

export function shouldRejected (promise) {
  return {
    'catch': (fn) => {
      return promise.then(
        () => { throw new Error('Expected promise to be rejected but it was fulfilled') },
        (reason) => { fn.call(promise, reason) }
      )
    }
  }
}

export function shouldFulfilled (promise) {
  return {
    'then': (fn) => {
      return promise.then(
        (value) => { fn.call(promise, value) },
        (reason) => { throw reason }
      )
    }
  }
}

// TEST VUEX ACTION
// ---
// describe('actions', () => {
//   it('getAllProducts', done => {
//     testAction(actions.getAllProducts, null, {}, [
//       { type: 'REQUEST_PRODUCTS' },
//       { type: 'RECEIVE_PRODUCTS', payload: { /* ... */ } }
//     ], done)
//   })
// })

export function testAction (action, payload, state, expectedMutations, done) {
  let count = 0

  const commit = (type, payload) => {
    const mutation = expectedMutations[count]
    try {
      expect(mutation.type).to.equal(type)
      if (mutation.payload) {
        expect(mutation.payload).to.deep.equal(payload)
      }
    } catch (error) {
      done(error)
    }
    count++

    if (count >= expectedMutations.length) {
      done()
    }
  }

  action({ commit, state }, payload)

  if (expectedMutations.length === 0) {
    expect(count).to.equal(0)
    done()
  }
}