Here is my code for a tooltip that toggles the CSS property display: block on MouseOver and on Mouse Out display: none.
it('should show and hide the message using onMouseOver and onMouseOut events respectively', () => {
const { queryByTestId, queryByText } = render(
<Tooltip id="test" message="test" />,
)
fireEvent.mouseOver(queryByTestId('tooltip'))
expect(queryByText('test')).toBeInTheDocument()
fireEvent.mouseOut(queryByTestId('tooltip'))
expect(queryByText('test')).not.toBeInTheDocument()
cleanup()
})
I keep getting the error TypeError: expect(...).toBeInTheDocument is not a function
Has anyone got any ideas why this is happening? My other tests to render and snapshot the component all work as expected. As do the queryByText and queryByTestId.
As mentioned by Giorgio, you need to install jest-dom. Here is what worked for me:
(I was using typescript)
npm i --save-dev @testing-library/jest-dom
Then add an import to your setupTests.ts
import '@testing-library/jest-dom/extend-expect';
Then in your jest.config.js you can load it via:
"setupFilesAfterEnv": [
"<rootDir>/src/setupTests.ts"
]
When you do npm i @testing-library/react make sure there is a setupTests.js file with the following statement in it
import '@testing-library/jest-dom/extend-expect';