text: import deepFreeze from 'deep-freeze';
  import reducer from '../../app/assets/javascripts/reducers/course_alerts';
  import {
    RECEIVE_ONBOARDING_ALERT
  } from '../../app/assets/javascripts/constants/course_alerts';
  import '../testHelper';
  
  describe('Course Alerts reducer', () => {
    let initialState;
    beforeEach(() => {
      initialState = {
        onboardingAlert: null
      };
      deepFreeze(initialState);
    });
    test('should return the initial state', () => {
      const state = reducer(undefined, { type: null });
      expect(state).toEqual(initialState);
    });
    describe('Onboarding Alert', () => {
      test('should merge the alert when received as an object', () => {
        const action = {
          type: RECEIVE_ONBOARDING_ALERT,
          data: { alerts: [{ message: 'Onboarding alert message' }] }
        };
        const state = reducer(initialState, action);
        const [alert] = action.data.alerts;
        expect(state.onboardingAlert).toEqual(alert);
      });
      test('should replace an existing alert when another is received', () => {
        const firstAction = {
          type: RECEIVE_ONBOARDING_ALERT,
          data: { alerts: [{ message: 'Alert Message One' }] }
        };
        const firstState = reducer(initialState, firstAction);
        const secondAction = {
          type: RECEIVE_ONBOARDING_ALERT,
          data: { alerts: [{ message: 'Alert Message Two' }] }
        };
        const secondState = reducer(firstState, secondAction);
        const [alert] = secondAction.data.alerts;
        expect(secondState.onboardingAlert).toEqual(alert);
      });
    });
  });
  