Testing with JEST : Redux Actions and Thunks

testing.jest.reduxactions.thunks.js

/* =============== CONSTANTS ============================ */

export   const AWS_SIGN_UP_SAVING = 'AWS_SIGNUP_SAVE';
export   const AWS_SIGN_UP_FAIL = 'AWS_SIGN_UP_FAIL';
export   const AWS_SIGN_UP_SUCCESS = 'AWS_SIGN_UP_SUCCESS';
export   const THROW_ERROR = 'THROW_ERROR';
export   const CLEAR_ERROR = 'CLEAR_ERROR';



/* ==================  ACTIONS ================================= */
import {
    THROW_ERROR, 
    CLEAR_ERROR,
    AWS_SIGN_UP_SAVING,
    AWS_SIGN_UP_FAIL,
    AWS_SIGN_UP_SUCCESS
} from '../_constants/actionTypes.js'

export function throwError(data) {
        return {
            type: THROW_ERROR,
            data
        }
    };
export function clearError(data) {
        return {
            type: CLEAR_ERROR,
            data
        }
    };
export function awsSignUpUser(data) {
        return {
            type: AWS_SIGN_UP_SAVING,
            data
        }
    };
export function awsSignUpUserFailed(data){
        return {
            type: AWS_SIGN_UP_FAIL,
            data
        }
}
export function awsSignUpUserSuccess(data){
    return {
        type: AWS_SIGN_UP_SUCCESS,
        data
    }
}


/** 
 * THUNKS
 */
export function AWS_SignUpUser(username, password) {
    return (dispatch => {
        const data = {username, password};
        return dispatch(this.awsSignUpUser(data));
    });
};


/* ====================== TESTS ============================== */

import * as ActionTypes from '../../_constants/actionTypes';
import * as ActionCreators from '../registerActions';

describe('Actions', () => {
    let username = "fake@fake.com";
    let password = "@Password1";

    it("Should start the process of registering a user", () => {
        const dispatch = jest.fn();
        const expected = {
            type: ActionTypes.AWS_SIGN_UP_SAVING,
            data: {username, password}
        };

        //we expect this to return a function since it is a thunk
        expect(typeof (ActionCreators.AWS_SignUpUser(username, password))).toEqual('function');

        //then we simulate calling it with dispatch as the store would do
        ActionCreators.AWS_SignUpUser(username, password)(dispatch);

        //finally assert that the dispatch was called with our expected action
        expect(dispatch).toBeCalledWith(expected);
    });

    it("should create an action to fail a signup", () => {
        const data =  {errorCode: 500, message: 'User already exists'};
        const expected = {
            type: ActionTypes.AWS_SIGN_UP_FAIL,
            data: data
        }

       const actual = ActionCreators.awsSignUpUserFailed(data);
        
       expect(actual).toEqual(expected);

    });

    it("should create an action to signup a user", () => {
        const data = {cognito_user: 'fake@fake.com'};
        const expected = {
            type: ActionTypes.AWS_SIGN_UP_SUCCESS,
            data
        }

       const actual = ActionCreators.awsSignUpUserSuccess(data);
        
       expect(actual).toEqual(expected);

    });

    it("should create an action to throw an error", () => {
        const data = {error: {code:500, mesage: 'Something went wrong'}};
        const expected = {
            type: ActionTypes.THROW_ERROR,
            data
        }

       const actual = ActionCreators.throwError(data);
        
       expect(actual).toEqual(expected);

    });

    it("should create an action to clear an error", () => {
        const data = {error: null}
        const expected = {
            type: ActionTypes.CLEAR_ERROR,
            data
        }

       const actual = ActionCreators.clearError(data);
        
       expect(actual).toEqual(expected);

    });

});