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---
title: "Testing"
description:
"Best practices for testing React components using Vitest and Jest."
---
When writing tests with Vitest or Jest, use the following practices to get the
best results.
:::note
In general, we recommend using [Vitest](https://vitest.dev/) over
[Jest](https://jestjs.io/) but the setup are similar.
:::
## Setup
Before writing tests, ensure your project has the necessary dependencies:
```sh
npm install --save-dev vitest jsdom @testing-library/dom @testing-library/jest-dom @testing-library/react @testing-library/user-event
```
## Configuration
Create the `vite.config.ts` file to configure Vitest.
```ts
import { defineConfig } from "vitest/config"
export default defineConfig({
// ...
test: {
globals: true,
environment: "jsdom",
setupFiles: "./setup-test.ts",
},
})
```
Setting `globals: true` will automatically import the Vitest globals and removes
the need to import `expect`, `test`, `describe`, etc.
## Setup Test File
Create the `setup-test.ts` file to configure the testing environment and mock
unimplemented APIs.
Here's a common example for Chakra v3 projects:
```ts
import "@testing-library/jest-dom/vitest"
import { JSDOM } from "jsdom"
import ResizeObserver from "resize-observer-polyfill"
import { vi } from "vitest"
import "vitest-axe/extend-expect"
const { window } = new JSDOM()
// ResizeObserver mock
vi.stubGlobal("ResizeObserver", ResizeObserver)
window["ResizeObserver"] = ResizeObserver
// IntersectionObserver mock
const IntersectionObserverMock = vi.fn(() => ({
disconnect: vi.fn(),
observe: vi.fn(),
takeRecords: vi.fn(),
unobserve: vi.fn(),
}))
vi.stubGlobal("IntersectionObserver", IntersectionObserverMock)
window["IntersectionObserver"] = IntersectionObserverMock
// Scroll Methods mock
window.Element.prototype.scrollTo = () => {}
window.Element.prototype.scrollIntoView = () => {}
// requestAnimationFrame mock
window.requestAnimationFrame = (cb) => setTimeout(cb, 1000 / 60)
// URL object mock
window.URL.createObjectURL = () => "https://i.pravatar.cc/300"
window.URL.revokeObjectURL = () => {}
// navigator mock
Object.defineProperty(window, "navigator", {
value: {
clipboard: {
writeText: vi.fn(),
},
},
})
// Override globalThis
Object.assign(global, { window, document: window.document })
```
## Custom Render
First, you need to create a custom render function to wrap your component in the
ChakraProvider.
```tsx title="test-utils/render.tsx"
// ./testing/render.tsx
import { Provider } from "@/components/ui/provider"
import { render as rtlRender } from "@testing-library/react"
export function render(ui: React.ReactNode) {
return rtlRender(<>{ui}</>, {
wrapper: (props: React.PropsWithChildren) => (
<Provider>{props.children}</Provider>
),
})
}
```
## Testing Components
Now, you can use the `render` function to test your components.
```tsx title="testing/render.tsx"
import { Button } from "@chakra-ui/react"
import { render } from "./testing/render"
test("renders a button", () => {
render(<Button>Click me</Button>)
expect(screen.getByText("Click me")).toBeInTheDocument()
})
```