Steps to Test Custom Hooks
Step 1: Install the necessary package in your application using the following command.
npm install --save-dev jest @testing-library/react-hooks
Step 2: Write a test file: For example, if you have a custom hook named useCustomHook
in a file named customHook.js
, you can create a corresponding test file like customHook.test.js
.
Step 3: Write Test Cases: Import renderHook
and act
from @testing-library/react-hooks
. Use renderHook
to render the custom hook in a testing environment. Write test cases to assert the correctness of values and handle changes.
import { renderHook } from '@testing-library/react-hooks';
import useCustomHook from './useCustomHook';
Step 4: Run Tests: Execute tests using your preferred test runner, usually Jest.
npm test
Adjust tests based on the specific behavior of your custom hook. The act
function is used to trigger side effects like function calls within the hook.
How to test custom Hooks in React ?
Custom Hooks in React are JavaScript functions that utilize built-in React hooks or other custom hooks to encapsulate reusable logic in functional components. They follow a naming convention where the function name starts with “use” (e.g., useCustomHook
). Custom hooks allow users to abstract complex logic into reusable units, promoting code reusability and maintainability in React applications.
Testing custom hooks is similar to testing regular functions, and you can use testing libraries like Jest along with testing utilities for React like @testing-library/react-hooks