How to test react-router with enzyme

Question

I am using enzyme+mocha+chai to test my react-redux project. Enzyme provides shallow to test component behavior. But I didn\'t find a way to test the router. I am using reac

Answer 1

This will only pass if the component is rendered successfully: It works with Redux and react-router including hooks.

import React from "react";

import { expect } from "chai";
import { mount } from "enzyme";
import { MemoryRouter, Route } from "react-router-dom";
import { createMockStore } from "redux-test-utils";
import { Provider } from "react-redux";


...
describe("<MyComponent />", () => {
    it("renders the component", () => {
    let props = {
      index: 1,
      value: 1
    };
    let state = {};

    const wrapper = mount(
      <Provider store={createMockStore(state)}>
        <MemoryRouter initialEntries={["/s/parameter1"]}>
          <Route path="/s/:camera">
            <MyComponent {...props} />
          </Route>
        </MemoryRouter>
      </Provider>
    );

    expect(wrapper.find(ProcessedFrames.WrappedComponent)).to.have.lengthOf(1);
  });
});

Answer 2

You can wrap your router inside a component in order to test it.

Routes.jsx

export default props => (
  <Router history={browserHistory}>
    ...
    <Route path="nurse/authorization" component{NurseAuthorization}/>
    ...
  </Route>
)

index.js

import Routes from './Routes.jsx';
...

ReactDOM.render(<Routes />, document.getElementById('root'));

Then you have to shallow render your Routes component, and you are able to create an object map to check the correspondance between path and related component.

Routes.test.js

import { shallow } from 'enzyme';
import { Route } from 'react-router';
import Routes from './Routes.jsx';
import NurseAuthorization from './NurseAuthorization.jsx';

it('renders correct routes', () => {
  const wrapper = shallow(<Routes />);
  const pathMap = wrapper.find(Route).reduce((pathMap, route) => {
    const routeProps = route.props();
    pathMap[routeProps.path] = routeProps.component;
    return pathMap;
  }, {});
  // { 'nurse/authorization' : NurseAuthorization, ... }

  expect(pathMap['nurse/authorization']).toBe(NurseAuthorization);
});

EDIT

In case you want to additionally handle the case of render props:

const pathMap = wrapper.find(Route).reduce((pathMap, route) => {
  const routeProps = route.props();
  if (routeProps.component) {
    pathMap[routeProps.path] = routeProps.component;
  } else if (routeProps.render) {
    pathMap[routeProps.path] = routeProps.render({}).type;
  }
  return pathMap;
}, {});

It will work only in case you render directly the component you want to test (without extra wrapper).

<Route path="nurse/authorization" render{() => <NurseAuthorization />}/>

Answer 3

I had my paths defined in another file for the dynamic router, so I am also testing that all the routes I am rendering as Routes are defined in my paths.js constants:

it('Routes should only have paths declared in src/routing/paths.js', () => {
  const isDeclaredInPaths = (element, index, array) => {
    return pathsDefined.indexOf(array[index]) >= 0;
  }
  expect(routesDefined.every(isDeclaredInPaths)).to.be.true;
});