React Testing Library & Jest-React Testing Library Guide

Example

render(<MyComponent />)

Scenario

Use render from RTL to render your React components in a virtual DOM for testing. This helps in verifying if the component renders without crashing and interacts correctly with user events.

Example

screen.getByText('Submit')

Scenario

RTL provides various query methods like getByText, getByRole, getByLabelText to find elements in the rendered component. These methods help in asserting the presence or absence of elements as a user would perceive them.

Example

fireEvent.click(button)

Scenario

fireEvent and userEvent from RTL allow simulating user interactions such as clicks, typing, and form submissions. This is crucial for testing component behavior in response to user actions.

Example

jest.mock('axios')

Scenario

Jest provides powerful mocking capabilities to replace real modules with mock implementations. This is particularly useful for isolating the component under test and controlling the data it interacts with.

Example

expect(element).toBeInTheDocument()

Scenario

Jest's extensive assertion library, combined with custom matchers like toBeInTheDocument from @testing-library/jest-dom, enables precise and expressive validation of component states and behaviors.