react jest mock useNavigate()

Question

"react-router-dom": "^6.0.0-alpha.5",

I have tried nearly everything.

I just want to mock this navigate() call from the useNavigate() hook. that's it. Simple. Nothing working.

No, i do not want to use Link. useNavigate is used programmatically in other places as well and I want to mock them too

import React from 'react'
import { useNavigate } from "react-router-dom"

export const Detail = () => {
    const navigate = useNavigate();
    return (
        <span onClick={() => navigate('/some/specific/route')}>
            some Text
        </span>
    )
}

I have tried these:

jest.mock('react-router-dom', () => {
    // Require the original module to not be mocked...
    const originalModule = jest.requireActual('react-router-dom');

    return {
        __esModule: true,
        ...originalModule,
        // add your noops here
        useNavigate: jest.fn(() => 'bar')
    };
});

import * as ReactRouterDom from "react-router-dom";
...
// cannot redefine property
          Object.defineProperty(ReactRouterDom, 'useNavigate', {
              configurable: true,
              value: jest.fn(() => 'bar')
          });

// doesnt work
          jest.mock('react-router-dom', () => ({
              useNavigate: jest.fn(() => jest.fn),
          }))

// doesnt work
jest.spyOn(ReactRouterDom, 'useNavigate', 'get').mockReturnValue(jest.fn(() => jest.fn));

// doesnt work
jest.spyOn(ReactRouterDom, 'useNavigate').mockReturnValue(jest.fn(() => jest.fn));

// doesnt work
const mockedUsedNavigate = jest.fn();

jest.mock('react-router-dom', () => ({
   ...jest.requireActual('react-router-dom') as any,
  useNavigate: () => mockedUsedNavigate,
}));

all of these either show "Cannot redefine Property 'useNavigate'", or that useNavigate() may be used only in the context of a <Router> component.

Seriously, any other import mock works fine.

What am I doing wrong?

MY MINIMUM RECREATED PROJECT: https://github.com/zacharytyhacz/useNavigateBug

Fraya

Answer 1

I had a similar concern that was fixed with this issue from react router

I would suggest you change the mock as is:

// pay attention to write it at the top level of your file
const mockedUsedNavigate = jest.fn();

jest.mock('react-router-dom', () => ({
   ...jest.requireActual('react-router-dom') as any,
  useNavigate: () => mockedUsedNavigate,
}));


// your describe/it/test blocks go down there

Hathcock

What error did it throw? Can you point to your example repo or show your test file? – Hathcock

it says same error in original post useNavigate() may be used only in the context of a <Router> component. – Fraya

Mind pasting your test file? – Hathcock

Here's my minimal project of the issue: github.com/zacharytyhacz/useNavigateBug – Fraya

Your mokedUseNavigate and jest mock(github.com/zacharytyhacz/useNavigateBug/blob/…) should be at the top level of the file, not inside "test", "it" or "describe": See this for reference: github.com/ReactTraining/react-router/issues/7811 – Hathcock

can you edit your answer / post new answer mentiong that?, I gotchu on this bounty – Fraya

@Fraya please try render(<BrowserRouter><YourComponent /></BrowserRouter>) – Impractical

Working, THX a lot. – Infield

Why does the jest.mock('react-router-dom'... have to be at the top level of the file? – Rutty

I already have that implementation but I can't make the navigate mock to be called. Here it is all the details of my issue. Please help. Thanks in advance. – Vorticella

Answer 2

Here's how I mock and assert on navigate() calls in my component tests:

import * as router from 'react-router'

const navigate = jest.fn()

beforeEach(() => {
  jest.spyOn(router, 'useNavigate').mockImplementation(() => navigate)
})

it('...', () => {
  ...
  expect(navigate).toHaveBeenCalledWith('/path')
})

Lucinalucinda

Testing implementation is only a workaround and is advised against mostly, but since I can't make it work with the accepted answer, I'll have to use such approach... – Barbate

@Enfieldli totally agree. However, there are situations where your component might do a redirect via navigate() when it receives certain prop(s). For such situations asserting on a call to navigate() in a unit test is totally fine, imo. On the other hand, for navigation events done via clicking, testing it a higher level (via cypress, for example) is advised. – Harmaning

Answer 3

You should be able to spy on useNavigate normally if you change your import from:

import { useNavigate } from "react-router-dom"

to

import { useNavigate } from "react-router"

Colourable

This is the only thing that worked for me. Otherwise I was blocked by TypeError: Cannot redefine property: useNavigate at Function.defineProperty (<anonymous>) – Hellcat

Answer 4

I'm using React testing Library. Per the documentation, I have a test utils file which exports a custom render method. The custom render method wraps the rendered component in mocked providers as well as a router. This enables me to do the following:

 it('redirects when span is clicked', async () => {
    const span = await screen.findByText('some text')
    await userEvent.click(span)
    await waitFor(() => expect(window.location.href).toContain('/some/sepcific/route'))
  })

To be fair, it's a different approach than what the OP asked specifically about. However, I think it's worth mentioning.

Levy

This answer saved me, at least for now. – Uralaltaic