What is React strict mode and what are its benefits?

TL;DR

React strict mode is a development tool that helps identify potential problems in an application. It activates additional checks and warnings for its descendants. It doesn't render any visible UI and doesn't affect the production build. The benefits include identifying unsafe lifecycle methods, warning about legacy string ref API usage, detecting unexpected side effects, and ensuring that components are resilient to future changes.

What is React strict mode and what are its benefits?

What is React strict mode?

React strict mode is a feature in React that helps developers identify potential problems in their applications. It is a wrapper component that you can use to wrap parts of your application to enable additional checks and warnings. It does not render any visible UI and does not affect the production build.

To use React strict mode, you can wrap your component tree with the StrictMode component:

import React from 'react';
import ReactDOM from 'react-dom';

ReactDOM.render(
  <React.StrictMode>
    <App />
  </React.StrictMode>,
  document.getElementById('root')
);

Benefits of React strict mode

Identifying unsafe lifecycle methods

React strict mode helps identify components that use unsafe lifecycle methods, such as componentWillMount, componentWillReceiveProps, and componentWillUpdate. These methods are considered unsafe because they can lead to bugs and unexpected behavior. React strict mode will warn you if any of your components use these methods.

Warning about legacy string ref API usage

React strict mode warns you if you are using the legacy string ref API. The string ref API is considered legacy and is not recommended for use in new code. Instead, you should use the callback ref API or the React.createRef API.

Detecting unexpected side effects

React strict mode helps detect unexpected side effects by intentionally double-invoking certain lifecycle methods and functions. This helps ensure that your components are resilient to future changes and that they do not rely on side effects that may not always be executed.

Ensuring components are resilient to future changes

By enabling React strict mode, you can ensure that your components are more resilient to future changes in React. The additional checks and warnings help you identify potential issues early, making it easier to maintain and update your codebase.

What is React strict mode and what are its benefits?

TL;DR