import * as React from 'react'
import {act, render, fireEvent, screen} from '../'
test('render calls useEffect immediately', () => {
const effectCb = jest.fn()
function MyUselessComponent() {
React.useEffect(effectCb)
return null
}
render()
expect(effectCb).toHaveBeenCalledTimes(1)
})
test('findByTestId returns the element', async () => {
const ref = React.createRef()
render(
)
expect(await screen.findByTestId('foo')).toBe(ref.current)
})
test('fireEvent triggers useEffect calls', () => {
const effectCb = jest.fn()
function Counter() {
React.useEffect(effectCb)
const [count, setCount] = React.useState(0)
return
}
const {
container: {firstChild: buttonNode},
} = render()
effectCb.mockClear()
fireEvent.click(buttonNode)
expect(buttonNode).toHaveTextContent('1')
expect(effectCb).toHaveBeenCalledTimes(1)
})
test('calls to hydrate will run useEffects', () => {
const effectCb = jest.fn()
function MyUselessComponent() {
React.useEffect(effectCb)
return null
}
render(, {hydrate: true})
expect(effectCb).toHaveBeenCalledTimes(1)
})
test('cleans up IS_REACT_ACT_ENVIRONMENT if its callback throws', () => {
global.IS_REACT_ACT_ENVIRONMENT = false
expect(() =>
act(() => {
throw new Error('threw')
}),
).toThrow('threw')
expect(global.IS_REACT_ACT_ENVIRONMENT).toEqual(false)
})
test('cleans up IS_REACT_ACT_ENVIRONMENT if its async callback throws', async () => {
global.IS_REACT_ACT_ENVIRONMENT = false
await expect(() =>
act(async () => {
throw new Error('thenable threw')
}),
).rejects.toThrow('thenable threw')
expect(global.IS_REACT_ACT_ENVIRONMENT).toEqual(false)
})