act does not support async callback
See original GitHub issueVersions
"react": "16.8.3"
"react-native": "0.59.5"
"react-test-renderer": "16.8.3"
"react-native-testing-library": "1.7.0"
Description
Unable to use async function as act
callback without console errors.
Either a console.error is emitted when not using act
in the test (see Demo 1)
or the test fails by using async callback in act
(see Demo 2)
Now supported in react-testing-library
:
https://github.com/testing-library/react-testing-library/releases/tag/v6.1.0
Demo 1 (not wrapping in act
)
import { render, act } from 'react-native-testing-library';
import Dialog from '...';
const Component = () => {
const [result, setResult] = React.useState(null);
return (
<View>
<Text>{result}</Text>
<Dialog
onSubmit={async value => {
setResult(await doSomethingAsync(value));
}}
/>
</View>
);
};
// ... then in test
const elem = render(<Component />);
const dialog = elem.getByType(Dialog);
await dialog.props.onSubmit('value');
Emits console error: <span style="color:red">
Warning: An update to Component inside a test was not wrapped in act(...).
When testing, code that causes React state updates should be wrapped into act(...):
act(() => {
/* fire events that update state */
});
/* assert on the output */
This ensures that you're testing the behavior the user would see in the browser. Learn more at https://fb.me/react-wrap-tests-with-act
</span>
Demo 2 (wrapping with act
-> test failure)
import { render, act } from 'react-native-testing-library';
import Dialog from '...';
const Component = () => {
const [result, setResult] = React.useState(null);
return (
<View>
<Text>{result}</Text>
<Dialog
onSubmit={async value => {
setResult(await doSomethingAsync(value));
}}
/>
</View>
);
};
// ... then in test
const elem = render(<Component />);
const dialog = elem.getByType(Dialog);
await act(() => dialog.props.onSubmit('value'));
test failure with error: <span style="color:red">
Warning: The callback passed to TestRenderer.act(...) function must not return anything.
It looks like you wrote TestRenderer.act(async () => ...) or returned a Promise from it's callback. Putting asynchronous logic inside TestRenderer.act(...) is not supported.
console.error node_modules/react-test-renderer/cjs/react-test-renderer.development.js:102
Warning: Do not await the result of calling TestRenderer.act(...), it is not a Promise.
</span>Issue Analytics
- State:
- Created 4 years ago
- Comments:5 (1 by maintainers)
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For now I am using the
jest --silent
to disable react logginghttps://github.com/facebook/jest/issues/7151