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Full code here: https://gist.github.com/js08/0ec3d70dfda76d7e9fb4

Hi,

  • I have an application where it shows different templates for desktop and mobile on basis of build environment.
  • I am successfully able to develop it where I need to hide the navigation menu for my mobile template.
  • right now I am able to write one test case where it fetches all the values through the proptypes and renders correctly
  • but not sure how to write the unit test cases when its mobile it should not render nav component.
  • I tried but I am facing an error...can you tell me how to fix it.
  • provding code below.

Test case

import {expect} from 'chai';
import React from 'react';
import TestUtils from 'react-addons-test-utils';
import {SportsTopPortion} from '../../../src/components/sports-top-portion/sports-top-portion.jsx';
require('../../test-utils/dom');


describe('"sports-top-portion" Unit Tests', function() {
    let shallowRenderer = TestUtils.createRenderer();

    let sportsContentContainerLayout ='mobile';
    let sportsContentContainerProfile = {'exists': 'hasSidebar'};
    let sportsContentContainerAuthExchange = {hasValidAccessToken: true};
    let sportsContentContainerHasValidAccessToken ='test'; 

    it('should render correctly', () => {
        shallowRenderer.render(<SportsTopPortion sportsWholeFramework={sportsContentContainerLayout} sportsPlayers={sportsContentContainerProfile} sportsAuthentication={sportsContentContainerAuthExchange} sportsUpperBar={{activeSportsLink:'test'}} />);
        //shallowRenderer.render(<SportsTopPortion sportsWholeFramework={sportsContentContainerLayout} sportsPlayers={sportsContentContainerProfile} hasValidAccessToken={sportsContentContainerHasValidAccessToken}  />);

        let renderedElement = shallowRenderer.getRenderOutput();
        console.log("renderedElement------->" + JSON.stringify(renderedElement));

        expect(renderedElement).to.exist;
    });

    it('should not render sportsNavigationComponent when sports.build is mobile', () => {
        let sportsNavigationComponent = TestUtils.renderIntoDocument(<SportsTopPortion sportsWholeFramework={sportsContentContainerLayout} sportsPlayers={sportsContentContainerProfile} sportsAuthentication={sportsContentContainerAuthExchange} sportsUpperBar={{activeSportsLink:'test'}} />);
        console.log("sportsNavigationComponent------->" + JSON.stringify(sportsNavigationComponent));

        //let footnoteContainer = TestUtils.findRenderedDOMComponentWithClass(sportsNavigationComponent, 'linkPack--standard');

        //expect(footnoteContainer).to.exist;
    });

});

Code snippet where test case need to be written

if (sports.build === 'mobile') {
    sportsNavigationComponent = <div />;
    sportsSideMEnu = <div />;
    searchComponent = <div />;
    sportsPlayersWidget = <div />;
}

Error

1) "sports-top-portion" Unit Tests should not render sportsNavigationComponent when sports.build is mobile:
     Invariant Violation: Could not find "store" in either the context or props of "Connect(SportsDatabase)". Either wrap the root component in a <Provider>, or explicitly pass "store" as a prop to "Connect(SportsDatabase)".
      at Object.invariant [as default] (C:\sports-whole-page\node_modules\invariant\invariant.js:42:15)
      at new Connect (C:\sports-whole-page\node_modules\react-redux\lib\components\createConnect.js:135:33)
      at [object Object].ReactCompositeComponentMixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactCompositeComponent.js:148:18)
      at [object Object].wrapper [as mountComponent] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at ReactDOMComponent.ReactMultiChild.Mixin.mountChildren (C:\sports-whole-page\node_modules\react\lib\ReactMultiChild.js:241:44)
      at ReactDOMComponent.Mixin._createContentMarkup (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:591:32)
      at ReactDOMComponent.Mixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:479:29)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at ReactDOMComponent.ReactMultiChild.Mixin.mountChildren (C:\sports-whole-page\node_modules\react\lib\ReactMultiChild.js:241:44)
      at ReactDOMComponent.Mixin._createContentMarkup (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:591:32)
      at ReactDOMComponent.Mixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:479:29)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at [object Object].ReactCompositeComponentMixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactCompositeComponent.js:225:34)
      at [object Object].wrapper [as mountComponent] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at ReactDOMComponent.ReactMultiChild.Mixin.mountChildren (C:\sports-whole-page\node_modules\react\lib\ReactMultiChild.js:241:44)
      at ReactDOMComponent.Mixin._createContentMarkup (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:591:32)
      at ReactDOMComponent.Mixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:479:29)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at [object Object].ReactCompositeComponentMixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactCompositeComponent.js:225:34)
      at [object Object].wrapper [as mountComponent] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at ReactDOMComponent.ReactMultiChild.Mixin.mountChildren (C:\sports-whole-page\node_modules\react\lib\ReactMultiChild.js:241:44)
      at ReactDOMComponent.Mixin._createContentMarkup (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:591:32)
      at ReactDOMComponent.Mixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactDOMComponent.js:479:29)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at [object Object].ReactCompositeComponentMixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactCompositeComponent.js:225:34)
      at [object Object].wrapper [as mountComponent] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at [object Object].ReactCompositeComponentMixin.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactCompositeComponent.js:225:34)
      at [object Object].wrapper [as mountComponent] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactReconciler.mountComponent (C:\sports-whole-page\node_modules\react\lib\ReactReconciler.js:37:35)
      at mountComponentIntoNode (C:\sports-whole-page\node_modules\react\lib\ReactMount.js:266:32)
      at ReactReconcileTransaction.Mixin.perform (C:\sports-whole-page\node_modules\react\lib\Transaction.js:136:20)
      at batchedMountComponentIntoNode (C:\sports-whole-page\node_modules\react\lib\ReactMount.js:282:15)
      at ReactDefaultBatchingStrategyTransaction.Mixin.perform (C:\sports-whole-page\node_modules\react\lib\Transaction.js:136:20)
      at Object.ReactDefaultBatchingStrategy.batchedUpdates (C:\sports-whole-page\node_modules\react\lib\ReactDefaultBatchingStrategy.js:62:19)
      at Object.batchedUpdates (C:\sports-whole-page\node_modules\react\lib\ReactUpdates.js:94:20)
      at Object.ReactMount._renderNewRootComponent (C:\sports-whole-page\node_modules\react\lib\ReactMount.js:476:18)
      at Object.wrapper [as _renderNewRootComponent] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactMount._renderSubtreeIntoContainer (C:\sports-whole-page\node_modules\react\lib\ReactMount.js:550:32)
      at Object.ReactMount.render (C:\sports-whole-page\node_modules\react\lib\ReactMount.js:570:23)
      at Object.wrapper [as render] (C:\sports-whole-page\node_modules\react\lib\ReactPerf.js:66:21)
      at Object.ReactTestUtils.renderIntoDocument (C:\sports-whole-page\node_modules\react\lib\ReactTestUtils.js:76:21)
      at Context.<anonymous> (C:/codebase/sports-whole-page/test/components/sports-top-portion/sports-top-portion-unit-tests.js:28:41)
      at callFn (C:\sports-whole-page\node_modules\mocha\lib\runnable.js:286:21)
      at Test.Runnable.run (C:\sports-whole-page\node_modules\mocha\lib\runnable.js:279:7)
      at Runner.runTest (C:\sports-whole-page\node_modules\mocha\lib\runner.js:421:10)
      at C:\sports-whole-page\node_modules\mocha\lib\runner.js:528:12
      at next (C:\sports-whole-page\node_modules\mocha\lib\runner.js:341:14)
      at C:\sports-whole-page\node_modules\mocha\lib\runner.js:351:7
      at next (C:\sports-whole-page\node_modules\mocha\lib\runner.js:283:14)
      at Immediate._onImmediate (C:\sports-whole-page\node_modules\mocha\lib\runner.js:319:5)

10 Answers10

225

It's pretty simple. You're trying to test the wrapper component generated by calling connect()(MyPlainComponent). That wrapper component expects to have access to a Redux store. Normally that store is available as context.store, because at the top of your component hierarchy you'd have a <Provider store={myStore} />. However, you're rendering your connected component by itself, with no store, so it's throwing an error.

You've got a few options:

  • Create a store and render a <Provider> around your connected component
  • Create a store and directly pass it in as <MyConnectedComponent store={store} /> , as the connected component will also accept "store" as a prop
  • Don't bother testing the connected component. Export the "plain", unconnected version, and test that instead. If you test your plain component and your mapStateToProps function, you can safely assume the connected version will work correctly.

You probably want to read through the "Testing" page in the Redux docs: https://redux.js.org/recipes/writing-tests.

edit:

After actually seeing that you posted source, and re-reading the error message, the real problem is not with the SportsTopPane component. The problem is that you're trying to "fully" render SportsTopPane, which also renders all of its children, rather than doing a "shallow" render like you were in the first case. The line searchComponent = <SportsDatabase sportsWholeFramework="desktop" />; is rendering a component that I assume is also connected, and therefore expects a store to be available in React's "context" feature.

At this point, you have two new options:

  • Only do "shallow" rendering of SportsTopPane, so that you're not forcing it to fully render its children
  • If you do want to do "deep" rendering of SportsTopPane, you'll need to provide a Redux store in context. I highly suggest you take a look at the Enzyme testing library, which lets you do exactly that. See http://airbnb.io/enzyme/docs/api/ReactWrapper/setContext.html for an example.

Overall, I would note that you might be trying to do too much in this one component and might want to consider breaking it into smaller pieces with less logic per component.

Aakash
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markerikson
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  • I tried but not sure how to do...can you update in my test cases –  Mar 25 '16 at 16:13
  • 1
    I'm assuming that in SportsTopPortion.js, you have `let SportsTopPortion = connect(mapStateToProps)(SomeOtherComponent)`. The easiest answer is to test that _other_ component, not the component returned by `connect`. – markerikson Mar 25 '16 at 16:38
  • 1
    Aha. Now I see what's happening. The problem is not with SportsTopPane itself. The problem is that you're doing a "full" render of SportsTopPane, not a "shallow" render, so React is trying to fully render all children. The error message refers to the line `searchComponent = ;`. _That_ is the connected component that is expecting a store and breaking. So, two new suggestions: either only do shallow rendering of SportsTopPane, or use a library like Enzyme to test. See http://airbnb.io/enzyme/docs/api/ReactWrapper/setContext.html . – markerikson Mar 25 '16 at 16:44
  • can you tell me how to write the test case for this scenario ``` but not sure how to write the unit test cases when its mobile it should not render nav component. ``` –  Mar 25 '16 at 17:52
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    Answering someone who is stuck or puzzled with the phrase "it's pretty simple" can come off as disparaging or harsh. Please use sparingly. – jayqui May 06 '19 at 21:05
  • It seems one of the options has been removed since this answer was posted. Trying to add `store={Store}` fails with `Invariant Violation: Passing redux store in props has been removed and does not do anything. To use a custom Redux store for specific components, create a custom React context with React.createContext(), and pass the context object to React Redux's Provider and specific components like: . You may also pass a {context : MyContext} option to connect` – ssc Jul 26 '19 at 17:26
  • @ssc : please update to React-Redux v7.x. That option was removed in v6, and re-added in v7, due to internal implementation changes. – markerikson Jul 27 '19 at 22:37
  • Good one on the edit update! This was my problem. Why is this not marked as the answered?! – ianbeks Sep 24 '19 at 13:07
120

Possible solution that worked for me with jest

import React from "react";
import { shallow } from "enzyme";
import { Provider } from "react-redux";
import configureMockStore from "redux-mock-store";
import TestPage from "../TestPage";

const mockStore = configureMockStore();
const store = mockStore({});

describe("Testpage Component", () => {
    it("should render without throwing an error", () => {
        expect(
            shallow(
                <Provider store={store}>
                    <TestPage />
                </Provider>
            ).exists(<h1>Test page</h1>)
        ).toBe(true);
    });
});
codeislife
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    works well, instead of having to pass props one by one. – gema Nov 26 '18 at 12:10
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    Thank you, a very nice solution. I had this problem because I am using a top-level App component with routing and the store is provided to the child app in each route so I don't have to pass props into the router. I changed it a little for my use. const wrapper = shallow(); expect(wrapper.contains()).toBe(true); – Little Brain Dec 26 '18 at 00:24
78

As the official docs of redux suggest, better to export the unconnected component as well.

In order to be able to test the App component itself without having to deal with the decorator, we recommend you to also export the undecorated component:

import { connect } from 'react-redux'

// Use named export for unconnected component (for tests)
export class App extends Component { /* ... */ }
 
// Use default export for the connected component (for app)
export default connect(mapStateToProps)(App)

Since the default export is still the decorated component, the import statement pictured above will work as before so you won't have to change your application code. However, you can now import the undecorated App components in your test file like this:

// Note the curly braces: grab the named export instead of default export
import { App } from './App'

And if you need both:

import ConnectedApp, { App } from './App'

In the app itself, you would still import it normally:

import App from './App'

You would only use the named export for tests.

Erowlin
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Peter
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7

When we put together a react-redux application we should expect to see a structure where at the top we have the Provider tag which has an instance of a redux store.

That Provider tag then renders your parent component, lets call it the App component which in turn renders every other component inside the application.

Here is the key part, when we wrap a component with the connect() function, that connect() function expects to see some parent component within the hierarchy that has the Provider tag.

So the instance you put the connect() function in there, it will look up the hierarchy and try to find the Provider.

Thats what you want to have happen, but in your test environment that flow is breaking down.

Why?

Why?

When we go back over to the assumed sportsDatabase test file, you must be the sportsDatabase component by itself and then trying to render that component by itself in isolation.

So essentially what you are doing inside that test file is just taking that component and just throwing it off in the wild and it has no ties to any Provider or store above it and thats why you are seeing this message.

There is not store or Provider tag in the context or prop of that component and so the component throws an error because it want to see a Provider tag or store in its parent hierarchy.

So that’s what that error means.

Daniel
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6

in my case just

const myReducers = combineReducers({
  user: UserReducer
});

const store: any = createStore(
  myReducers,
  applyMiddleware(thunk)
);

shallow(<Login />, { context: { store } });

jose920405
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6

For me it was import issue, hope it helps. default import by WebStorm was wrong.

replace

import connect from "react-redux/lib/connect/connect";

with

import {connect} from "react-redux";
ATQSHL
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6

This happened to me when I upgraded. I had to downgrade back.

react-redux ^5.0.6 → ^7.1.3

codie
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3

jus do this import { shallow, mount } from "enzyme";

const store = mockStore({
  startup: { complete: false }
});

describe("==== Testing App ======", () => {
  const setUpFn = props => {
    return mount(
      <Provider store={store}>
        <App />
      </Provider>
    );
  };

  let wrapper;
  beforeEach(() => {
    wrapper = setUpFn();
  });
Hilal Aissani
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2

in the end of your Index.js need to add this Code:

import React from 'react';
import ReactDOM from 'react-dom';
import { BrowserRouter  } from 'react-router-dom';

import './index.css';
import App from './App';

import { Provider } from 'react-redux';
import { createStore, applyMiddleware, compose, combineReducers } from 'redux';
import thunk from 'redux-thunk';

///its your redux ex
import productReducer from './redux/reducer/admin/product/produt.reducer.js'

const rootReducer = combineReducers({
    adminProduct: productReducer
   
})
const composeEnhancers = window._REDUX_DEVTOOLS_EXTENSION_COMPOSE_ || compose;
const store = createStore(rootReducer, composeEnhancers(applyMiddleware(thunk)));


const app = (
    <Provider store={store}>
        <BrowserRouter   basename='/'>
            <App />
        </BrowserRouter >
    </Provider>
);
ReactDOM.render(app, document.getElementById('root'));
Mehrdad
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0

Add mock of library method which is causing this. In my case it was happening for useIsConnected of react-native-offline. So I mocked it like below:

jest.mock("react-native-offline", () => ({ useIsConnected: jest.fn() }));
Yuvraj Patil
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