The devDependency react-native was updated from 0.57.5 to 0.57.6.

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react-native is a devDependency of this project. It might not break your production code or affect downstream projects, but probably breaks your build or test tools, which may prevent deploying or publishing.

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Hey there,

I'm using a FlatList with a ListHeaderComponent in a component and I'm having issues getting render to work without errors. The error is below:

    Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: object.

      at invariant (node_modules/fbjs/lib/invariant.js:42:15)
      at getFiberTagFromObjectType (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:1693:9)
      at createFiberFromElement (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:1653:20)
      at reconcileSingleElement (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:4670:23)
      at reconcileChildFibers (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:4727:35)
      at reconcileChildrenAtExpirationTime (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:5098:28)
      at reconcileChildren (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:5089:3)
      at mountIndeterminateComponent (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:5524:5)
      at beginWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:5903:14)
      at performUnitOfWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:7949:12)

More detail:

  console.error node_modules/react-test-renderer/cjs/react-test-renderer.development.js:6309
    The above error occurred in one of your React components:
        in Unknown (at VirtualizedList.js:761)
        in View (created by View)
        in View (at VirtualizedList.js:767)
        in VirtualizedCellWrapper (at VirtualizedList.js:764)
        in View (created by View)
        in View (at ScrollViewMock.js:31)
        in RCTScrollView (created by _class)
        in _class (at ScrollViewMock.js:29)
        in ScrollView (at VirtualizedList.js:1062)
        in VirtualizedList (at FlatList.js:663)

Associated code:

https://github.com/facebook/react-native/blob/master/Libraries/Lists/VirtualizedList.js#L753

Versions:

"react": "16.6.3",
"react-native": "0.57.8",

Repro:

https://github.com/wmcbain/RNTestingTestingRepro

Is there a suggested way to mock this in order to get past the error?

Ask your Question

I'd like to know how to test context-api with react-native-testing-library.
It is supported int react-testing-library as in #296. Also, [useContext] could be covered which was addressed in #283.

I searched for api doc and I am not seeing any use-case for this one.

Linaria recently adopted release-it: callstack/linaria#241
We should explore this too :)

Hi,
I have this component:

import {
	Container,
	Content,
	Text,
} from 'native-base';


<Container style={styles.container}>			
	<Content padder>
		<Text testID={'emptyCasesList'}>Cases list is empty</Text>
	</Content>
</Container>

But the test can't find the 'emptyCasesList' element. when I run debug.deep, I can't see the <Content/> element nor the <Text>.
BUT - when I remove the <Content/> element (leaving just the <Text/>), test passes and I see the <Text/> element.
If the answer is something like "NativeBase is mocking the <Content/> in tests" - could you please elaborate further?

Thanks.

I think we'll go with CircleCI

Hooks work fine even without it, but you'll likely need to add asynchrony to your code. With act() you'll be able to achieve the same results in synchronous manner.

See: https://reactjs.org/blog/2019/02/06/react-v16.8.0.html#testing-hooks

I'm using wix's react-native-ui-lib with react-native-testing-library. They have extended some core rn elements (eg Text) so that their elements are used instead. Example: https://github.com/wix/react-native-ui-lib/wiki/USAGE

When I use Text element from react-native-ui-lib, the getByText helper fails to find the text. However, when I switch to the RN Text component, the tests pass as I expect.

Not sure what the right way forward is here so thought I would log an issue to discuss.

(Right now I'm just using toJSON and a string regex to assert that the text was found.)

The devDependency @types/react was updated from 16.7.8 to 16.7.9.

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Your Greenkeeper Bot 🌴

I'm trying to figure out why it seems like the fireEvent.press function always seem to trigger a callback even though it shouldn't be registered. My use case is that I'm trying to write a test that makes sure that onPress isn't called if the component is "disabled".

Trying to mimic the behaviour below...

  const MyComponent = _props => (
    <View>
      <TouchableHighlight testID={'touchable'}>
        <Text>{'Foo'}</Text>
      </TouchableHighlight>
    </View>
  )

  const pressedCallback = jest.fn()
  const { getByTestId } = render(<MyComponent onPress={() => pressedCallback('bar')} />)
  fireEvent.press(getByTestId('touchable'))
  expect(pressedCallback).not.toBeCalled() //Expected mock function not to be called but it was called with: ["bar"]

If i have the following component setup and then render(<SignUp />); in a test file. Trying to check if the event fires on press does not register.

export class SignUp extends Component {
  handleSignUp = () => ({})

  render() {
    return (
      <View>
        <TouchableOpacity testID="sign-up-button" onPress={this.handleSignUp}>
          <Text>Sign up</Text>
        </TouchableOpacity>
      </View>
    )
  }
}

test('should invoke specified event', () => {
  const handleSignUp = jest.fn();
  const { getByTestId } = render(<SignUp />);
  fireEvent(getByTestId('sign-up-button'), 'press');
  expect(handleSignUp).toHaveBeenCalled();
});

Expected mock function to have been called, but it was not called.

As discussed in this thread:

https://twitter.com/thymikee/status/1050432901945483265

It would be good to both spell out that Enzyme can be set up with deep rendering with mount(), which I plan to update documentation for here:

enzymejs/enzyme#1375

But it would also be good to highlight the benefits of using react-native-testing-library at the same time. As @thymikee mentioned:

Yup, but I don't want to use jsdom as RN is not web. Also Enzyme makes it too easy to write bad tests that assert on implementation details. [...]

I might be able to help with documentation here soon if no one else wants to pick this up, though I might try out the library myself first when I get a chance so I can better speak to it.

I am trying to run simple test case in TypeScript project but I am getting

> mocha
/myApp/node_modules/react-native-testing-library/src/index.js:2
import render from './render';
^^^^^^
SyntaxError: Unexpected token import

This means that you guys are publishing the project code in ES6 even though node_modules should be released as ES5.

Could you compile the library code to ES5 and republish that :)

Hi, thank you for a great testing library!
Is there any additional setup I need to do to make the snapshot testing work smoothly with [styled-components](https://github.com/styled-components/styled-components)?

The generated snapshots are not useful as they're missing the entire CSS.

Snapshot with react-test-renderer:

// Jest Snapshot v1, https://goo.gl/fbAQLP

exports[`Component SubmitButton renders correctly 1`] = `
<View
  accessible={true}
  isTVSelectable={true}
  onResponderGrant={[Function]}
  onResponderMove={[Function]}
  onResponderRelease={[Function]}
  onResponderTerminate={[Function]}
  onResponderTerminationRequest={[Function]}
  onStartShouldSetResponder={[Function]}
  style={
    Object {
      "alignItems": "center",
      "backgroundColor": "#006a35",
      "borderColor": "rgba(0, 0, 0, 0)",
      "borderRadius": 24,
      "borderWidth": 1.5,
      "height": 48,
      "justifyContent": "center",
      "marginBottom": 40,
      "marginHorizontal": 36,
      "opacity": 1,
    }
  }
>
  <Text
    labelColor="#fff"
    style={
      Array [
        Object {
          "color": "#fff",
          "fontFamily": "UniversLTPro-65Bold",
          "fontSize": 12,
          "letterSpacing": 1,
          "lineHeight": 14,
        },
      ]
    }
  >
   
  </Text>
</View>
`;

Snapshot with react-native-testing-library:

// Jest Snapshot v1, https://goo.gl/fbAQLP

exports[`Component SubmitButton renders correctly 1`] = `
Object {
  "output": <ForwardRef
    disabled={false}
    onPress={[Function]}
  >
    <ForwardRef
      labelColor="#fff"
    >
      
    </ForwardRef>
  </ForwardRef>,
}
`;

As you can see, the snapshot spits out a bunch of ForwardRef components and doesn't list the CSS so the snapshot test only shows props passed to components and is not really useful.

Is there any additional setup I need here or do we need to add support for this in react-native-testing-library or styled-components?

We should either

1. make it explicit to install the typings using flow-typed or
2. add node_modules/react-native-testing-library/flow-typed/ to [libs] in .flowconfig
3. move the ReactTestInstance/ReactTestRendererJSON to our codebase.

I'm leaning towards options 1 & 2 as both make sense in some scenarios.

cc @Esemesek

The devDependency release-it was updated from 10.0.8 to 10.0.9.

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Your Greenkeeper Bot 🌴

Hi guys, thanks for cool library!
Have a question for you:
Is there any way I can test onPressIn and onPressOut?

I'm using React Native Elements and testing my components using react-native-testing-library. However, when I try to use the getByType/getAllByType/queryByType/queryAllByType APIs, TypeScript complains about props that are marked by the component as required. One example of a component with a required attribute is the Icon component from React Native Elements.

Consider this example:

// Icon has a required prop `name`
import { Icon, Input } from 'react-native-elements';

// Current signature used by getByType/getAllByType/queryByType/queryAllByType
// getByType: (type: React.ComponentType) => ReactTestInstance;
// getAllByType: (type: React.ComponentType) => Array<ReactTestInstance>
// queryByType: (type: React.ComponentType) => ReactTestInstance | null;
// queryAllByType: (type: React.ComponentType) => Array<ReactTestInstance> | [];

const inst = render(<Input leftIcon={{ name: 'visibility-off' }} />);
// TypeScript fails!
const icon = inst.getByType(Icon);

Error shown

[ts]
Argument of type 'typeof Icon' is not assignable to parameter of type 'ComponentType<{}>'.
  Type 'typeof Icon' is not assignable to type 'ComponentClass<{}, any>'.
    Types of parameters 'props' and 'props' are incompatible.
      Type '{}' is not assignable to type 'Readonly<IconProps>'.
        Property 'name' is missing in type '{}'. [2345]

I started using the library in our react-native project and I keep facing problems to wait until ApolloClient finish loading. Why don't we implement a waitForElementToDiminish so we can always add the loading label/testID and simplify our waits.

Versions

• Expo v32.0.0
• jest-expo v32.0.0
• React v16.5.0
• NativeBase v2.12.1
• react-native-testing-library v1.6.1
• react-test-renderer v16.8.4
• OS: multiple

Description

As of v1.6.1, I am receiving the following error when trying to test a NativeBase Picker using getByText (the same tests pass in v1.6.0):

Currently the only supported library to search by text is "react-native".

Cannot read property 'toString' of null

This only seems to happen when there are multiple tests.

Reproducible Demo

https://github.com/wKovacs64/rntl-161-repro

I'm attempting to create a "Hello World" component to try out RNTL with Mocha and I'm getting an error attempting to render the component.

Full reproduction repo: https://github.com/CodingItWrong/RNTLTestMocha

Component:

import React from 'react';
import { View, Text } from 'react-native';

export default function Hello() {
  return <View>
    <Text>asdf</Text>
  </View>;
}

Test:

import { expect } from 'chai';
import React from 'react';
import { render, fireEvent } from 'react-native-testing-library';

import Hello from '../Hello';

describe('Hello', () => {
  it('displays the message', () => {
    const { debug, getByText } = render(<Hello />);

    debug();

    expect(getByText('asdf')).not.to.be.null;
  });
});

Error:

  1) Hello
       displays the message:
     Error: Cannot find module 'View'
      at require (internal/module.js:11:18)
      at Object.get View [as View] (node_modules/react-native/Libraries/react-native/react-native-implementation.js:167:12)
      at Hello (Hello.js:5:11)
      at mountIndeterminateComponent (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:6889:13)

I have react-test-renderer installed. Does RNTL work with Mocha? Am I missing another dependency? If it's Jest-only I think it would be good to add a note in the README; I can PR that if so.

The render section of the README says:

For convenience it also returns react-test-renderer's instance and renderer objects, in case you need more control.

But it doesn't. But it should! 🙂 Looks like they were removed in e6ac5ad, but I think they would be valuable (at least renderer). Was there a reason they were removed?

PR incoming to add them back.

There's never too little. As a part of it we could show examples with Redux, Apollo, Relay, React Navigation, etc.

The devDependency conventional-changelog-cli was updated from 2.0.5 to 2.0.7.

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Your Greenkeeper Bot 🌴

We use Flow internally, because that's what React Native comes with by default. Would be cool to add TS typings though :)

I love to have react-native-testing testing approach in RN, and I'm starting to use it.

I can render almost any RN element, unless FlatList and SectionList. Somehow they are never renderer when I try to access the elements I render with renderItem, additionally when I check with debug() is like if they are omitted from the rendering.

What should I do to get them working?

There's a lot of information in the Readme right now. We should move the API and examples into separate files and then maybe generate a website out of it with Docusaurus.

I wrote a helper function to retrieve state after a changeText or press event. Is there a better way to do this?

My components are all wrapped in styled-component tags as well..

const getState = instance => {
  const [ReactTestInstance] = instance.children;
  const {
    stateNode: { state },
  } = ReactTestInstance['_fiber'].memoizedProps.children['_owner'];
  return state;
};

In React Native it is okay to pass a number as a child for a <Text /> element. So

<Text>2<Text />

is the same as

<Text>{"2"}<Text />

or

<Text>2.toString()<Text />

But since getByText only accepts a string as it's input, you can't find the element if it's being rendered in the first way.

This took me quite some time to debug and I think it's very counter-intuitive. Maybe there is a good solution so getByText finds everything rendered between <Text /> tags?

The devDependency eslint was updated from 5.14.0 to 5.14.1.

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Your Greenkeeper Bot 🌴

💅

I get an error

Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: object.

when I test a component that looks something like this

<View>{this.props.children({ status: this.state.status })}</View>

import React from 'react';
import { render, fireEvent } from 'react-native-testing-library';
import Providers from '../../../containers/Providers';
import SignIn from '../../../components/views/SignIn';

test('basic form validation and jwt retrieval', () => {
  const element = React.createElement(Providers,null, React.createElement(SignIn));

  const { getByText, getByTestId, getByName } = render(element);
  const component = getByName('StyledNativeComponent');
  const username = getByTestId('username');
  const password = getByTestId('password');
  const signIn = getByText(/sign in/i);

  // submit valid user
  fireEvent.changeText(username, 'USER');
  fireEvent.changeText(password, 'PASS');
  fireEvent.press(signIn);
});

How can I access the result from fireEvent.press(signIn)? The result is a promise (JWT) that has token etc in it.

What's the best approach to handle this kind of a test that has promises in it?

I have a TextInput component being rendered by a redux-form Field component.

When I call fireEvent.changeText(input, 'hello') on my component it works if I've fetched the input using getByPlaceholder, but fails if I use getByTestId. The error:

No handler function found for event: changeText

Here's code to reproduce the issue:

import React from 'react'
import { Field, reduxForm } from 'redux-form'
import { TextInput } from 'react-native'

const BaseInput = props => (
  <TextInput onChangeText={() => console.log('text changed')} {...props} />
)

const ReduxFormField = props => <Field component={BaseInput} {...props} />

const Input = () => (
  <ReduxFormField name="test" placeholder="placeholder" testID="testID" />
)

export default reduxForm({ form: 'DemoForm' })(Input)

And the tests:

...
import Input from '..'

describe('<Input>', () => {
  it('should be found by placeholder', () => {
    const { getByPlaceholder, unmount } = render(<Input />)
    const input = getByPlaceholder('placeholder')
    expect(input).toBeDefined()
    fireEvent.changeText(input, 'hello')
    unmount()
  })
  it('should be found by testID', () => {
    const { getByTestId, unmount } = render(<Input />)
    const input = getByTestId('testID')
    expect(input).toBeDefined()
    fireEvent.changeText(input, 'hello')
    unmount()
  })
})

I noticed this when I removed the placeholder from an input and needed to fetch it in a different way. I didn't expect any behaviour to be different when getting the same component with different queries.

I am not sure if this is a problem of react-native-testing-library or react-native-vector-icons.

Versions

"react": "^16.8.1",
"react-native": "^0.58.4",
"react-native-testing-library": "^1.5.0",
"react-test-renderer": "^16.8.1"

Description

    TypeError: Cannot read property 'default' of undefined

      at new Icon (node_modules/react-native-vector-icons/lib/create-icon-set.js:30:104)
      at constructClassInstance (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:3422:22)
      at updateClassComponent (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:6592:9)
      at beginWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:7549:20)
      at performUnitOfWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:11218:16)
      at workLoop (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:11250:28)
      at renderRoot (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:11333:11)
      at performWorkOnRoot (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:12221:11)
      at performWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:12133:11)
      at performSyncWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:12107:7)

Reproducible Demo

The test where the error happens:

MenuItems/test.tsx

describe("Prop: onPress", () => {
    const onPressMock = jest.fn();

    it("calls the passed callback when the menuItems(TouchableOpacity) was pressed", () => {
      const { getByTestId } = render(
        <MenuItems
          {...testProps}
          setModalVisible={onPressMock}
          setView={onPressMock}
        />
      );

      fireEvent.press(getByTestId("123"));
      expect(onPressMock).toHaveBeenCalledTimes(1);
    });
  });

MenuItems/index.tsx

export default class MenuItems extends Component<IProps> {
  public render() {
    return (
      <View style={styles.containerWrapper}>
        {this.props.icons.map(item => (
          <TouchableOpacity
            onPress={() => {
              this.props.setModalVisible();
              this.props.setView(item.id);
            }}
            key={item.id}
            style={styles.container}
          >
            <Icon name={item.icon} size={30} style={styles.icon} />
            <Text style={styles.text}>{item.name}</Text>
          </TouchableOpacity>
        ))}
      </View>
    );
  }
}

Took this code straight from your examples, but instead of looking for testId, I tried to look for the text:

  const {  getByText } = render(
    <ScrollView testID="scroll-view">
      <Text>XD</Text>
    </ScrollView>
  );

  getByText("XD");

Changing ScrollView to View makes it pass.

Am I doing something wrong?

See https://github.com/kentcdodds/react-testing-library#fireeventeventnamenode-htmlelement-eventproperties-object.

In RN world we could use it like

fireEvent.press(button);
fireEvent.doublePress(button);
fireEvent.changeText(textInput);
fireEvent.scroll(scrollView);

I'd like this to only have events that can be triggered by the user on core components.
Since any "basic" component like Picker, Checkbox, RadioButton can (and usually is) be implemented in user-land, I don't think there's room for so many events as in DOM world.

Accessing props directly would still be possible, because we probably shouldn't care about underlying native implementation (e.g. for gesture handlers)

The devDependency react-native was updated from 0.57.7 to 0.57.8.

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Your Greenkeeper Bot 🌴

Currently we use shallow rendering as a way to generate small snapshots, e.g. for snapshot-diff lib.
As much as I'm a fan of deep rendering I think in some cases, e.g. if one wants to test components as units, or speed up some tests that don't require deep rendering, it may make sense to assert on shallow output.
However, due to shallow renderer limitations, one couldn't rely on all lifecycle methods (which may be less relevant once Hooks take over the scene, still an implementation detail though).

In terms of API, shallow would just mimic render, so it should be easy to swap in certain conditions.

Testing eventListener in componentDidMount

Hey folks,

I have a react-native component that is listening to Linking url event. How would I fire that Event with react-native-testing-library?

Example:

import React, { PureComponent } from 'react';
import { View, Text, Linking, ActivityIndicator } from 'react-native';
import SafariView from 'react-native-safari-view';

class WebAuthView extends Component<Props, State> {
  componentDidMount() {
        Linking.addEventListener('url', this.handleAuthUrl);
        SafariView.addEventListener('onDismiss', this.handleDismiss);
   }

   componentWillUnmount() {
       Linking.removeEventListener('url', this.handleAuthUrl);
       SafariView.removeEventListener('onDismiss', this.handleDismiss);
   }

   handleAuthUrl = ({url}) => {
     // Implementation goes here
   }

   render() {
     // ....
   }
}

The devDependency react-native was updated from 0.57.4 to 0.57.5.

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react-native is a devDependency of this project. It might not break your production code or affect downstream projects, but probably breaks your build or test tools, which may prevent deploying or publishing.

Your Greenkeeper Bot 🌴

I would expect that something like this will be possible.
In my test scenario at first I add text content to the TextInput, then I test if text content exists, then I click on the delete button and I would like to test if input will be clear.

expect(getByText('content')).not.toBeDefined();

but I throw the exception with this No instances found

Created a fresh Expo app and tried to use waitForElement, but it throws. Works fine in vanilla RN app.

Test:

it('renders', async () => {
  const { getByText } = render(<App />);

  await waitForElement(() => getByText(/working/));
});

Result:

TypeError: Promise constructor's argument is not a function

     7 |     const { getByText } = render(<App />);
     8 | 
  >  9 |     await waitForElement(() => getByText(/working/));
    10 |   });
    11 | });
    12 | 
    
    at new Promise (node_modules/promise/lib/core.js:59:11)
    at resolve (node_modules/react-native-testing-library/src/waitForElement.js:8:26)
    at Object.getByText (App.test.js:9:32)
    at tryCatch (node_modules/regenerator-runtime/runtime.js:62:40)
    at Generator.invoke [as _invoke] (node_modules/regenerator-runtime/runtime.js:296:22)
    at Generator.prototype.(anonymous function) [as next] (node_modules/regenerator-runtime/runtime.js:114:21)
    at tryCatch (node_modules/regenerator-runtime/runtime.js:62:40)
    at invoke (node_modules/regenerator-runtime/runtime.js:152:20)
    at node_modules/regenerator-runtime/runtime.js:195:11
    at tryCallTwo (node_modules/promise/lib/core.js:45:5)

I'm assuming it has something to do with Expo's jest-expo preset, but I haven't narrowed it down yet.

Reproduction repo if anyone wants to mess with it: https://github.com/wKovacs64/rntl-expo-test

See https://github.com/kentcdodds/react-testing-library#query-apis.
Basically: instead of throwing, return null.

When I use Picker component of native base, it is not rendered as select in DOM. Is there a work around for that?

I noticed that this library doesn't expose a cleanup function like react-testing-library does. Is this intentional? Could you clear this issue up in the readme?

• CONTRIBUTING.md
• CODE_OF_CONDUCT.md
• LICENSE.md

Hi,
love this library!
just wondering if your planning to get the jest-dom/extend-expect functions converted to Native?
I have a bunch of tests where I introspect text results ...
I can do a getByText but in some cases I need to get all text for a parent Text component that contains a bunch of child Text components.
Thanks for your help,
/Stephen.

Currently we use Metro preset to transpile our files, which does a lot of transforms, that are not really necessary for running in Node 6+ (lowest actively supported version) environment.

It should be totally fine if we transformed our sources with @babel/preset-env with Node 6 target.

Currently the project is tested internally on a project I'm involved.

Technically we could test the library with pure React, without setting up React Native (by mocking some core components), which would massively simplify git checkout and maintenance, so I'm currently drawn into this direction. We can also think about using Expo as a testing example.

Looking forward for simplest, yet comprehensive way of doing this.