eslint-plugin-react-hooks

The eslint-plugin-react-hooks is a linting plugin for ESLint that provides rules for ensuring the correct usage of React Hooks. With the eslint-plugin-react-hooks, you can catch errors and enforce best practices when using Hooks in your React application.

Installation

To install the eslint-plugin-react-hooks plugin, you can use the npm package manager:

npm install eslint-plugin-react-hooks --save-dev

Usage

To use the eslint-plugin-react-hooks plugin in your ESLint configuration, you need to add it to the plugins array and enable the rules that you want to use:

// .eslintrc.js
module.exports = {
  // ...
  plugins: ['react-hooks'],
  rules: {
    'react-hooks/rules-of-hooks': 'error',
    'react-hooks/exhaustive-deps': 'warn',
  },
};

The plugin provides two rules:

• rules-of-hooks: This rule enforces that Hooks are called in the top level of a functional component or a custom Hook. It reports an error if Hooks are called in loops, conditions, or nested functions.
• exhaustive-deps: This rule enforces that all dependencies of a Hook are declared in the dependency array. It reports a warning if a dependency is missing.

Examples

Here are some examples of how the eslint-plugin-react-hooks plugin can be used in your ESLint configuration:

Example 1: Enforce rules of Hooks

To enforce the rules of Hooks in your application, you can enable the rules-of-hooks rule:

// .eslintrc.js
module.exports = {
  // ...
  plugins: ['react-hooks'],
  rules: {
    'react-hooks/rules-of-hooks': 'error',
  },
};

With this rule enabled, you will get an error if you use Hooks in loops, conditions, or nested functions:

// This will trigger the error: "React Hooks must be called in the exact same order in every component render"
function MyComponent(props) {
  const [count, setCount] = useState(0);

  if (count === 0) {
    useEffect(() => {
      // ...
    });
  }

  return <div>{count}</div>;
}

Example 2: Check exhaustive dependencies

To check that all dependencies of a Hook are declared in the dependency array, you can enable the exhaustive-deps rule:

// .eslintrc.js
module.exports = {
  // ...
  plugins: ['react-hooks'],
  rules: {
    'react-hooks/exhaustive-deps': 'warn',
  },
};

With this rule enabled, you will get a warning if you forget to add a dependency to the dependency array:

// This will trigger the warning: "React Hook useEffect has a missing dependency: 'count'"
function MyComponent(props) {
  const [count, setCount] = useState(0);

  useEffect(() => {
    // ...
  }, []);
  
  return <div>{count}</div>;
}

Conclusion

The eslint-plugin-react-hooks is a powerful tool that can help you write better React code by enforcing best practices and catching errors in your Hooks. By using this plugin, you can ensure that your React components are efficient, easy to maintain, and bug-free.