React mocha testing props.history

Question

I'm trying to test a function with mocha and nock, but got an error : Cannot read property 'data' of undefined at data

Here is my code

Methode to test:

export const registerUser = (userData, history) => dispatch => {
  axios
    .post("/api/v3/user", userData)
    .then( res => {      
      history.push("/login")
      return res;
    }) 
.catch(err =>
  dispatch({
    type: GET_ERRORS,
    payload: err.response.data
  })
);
};

Test:

describe('Post registerUser', () => {    
beforeEach(() => {
  nock('http://localhost')
    .post('/api/v3/user', userData )
    .reply(200, registerResponseValide);
});

it('Register valide', () => {
    const dispatchSpy = sinon.spy();
     return registerUser(userData, history)(dispatchSpy)
      .then(response => {
        //expect an object back
        expect(typeof response).to.equal('object');
        expect(response.data.id).to.equal(registerResponseValide().id)
      })
  });
});

Thanks for your help

Answer 1

The problem with registerUser is that it doesn't return a promise, this makes testing more complicated.

It should be:

export const registerUser = (userData, history) => dispatch => {
  return axios...
};

history.push should be a stub:

const history = { push: sinon.stub() };
return registerUser(userData, history)(dispatchSpy)...

Then it can be tested that it was called with correct argument.