ReactJS TestRenderer.create() Method

React.js library is all about splitting the app into several components. Each Component has its own lifecycle. React provides us some in-built methods that we can override at particular stages in the life-cycle of the component.

In this article, we will know how to use TestRenderer.create() method. This method is used to create a TestRenderer instance with the passed React element.

Creating React Application And Installing Module:

• Step 1: Create a React application using the following command

  
  
  

  npx create-react-app foldername

• Step 2: After creating your project folder i.e. foldername, move to it using the following command.

  cd foldername

• Step 3: Install the required module using the following command.

  npm install react-test-renderer

Project Structure: It will look like the following.

Example 1: Write down the following code in the App.js file. Here, App is our default component where we have written our code.

App.js

import React from 'react';
import TestRenderer from 'react-test-renderer';

// Defining our App Component
const App = () => {

  // Function to demonstrate TestRenderer.create() method
  function testRenderFun() {
    const renderer = TestRenderer.create(
      <div>GeeksforGeeks
      TestRenderer.create() method
      </div>
    );
    console.log(renderer);
  }

  // Function Call
  testRenderFun();

  // Returning our JSX code
  return <>
    <p>
      GeeksforGeeks TestRenderer.create() method
    </p>

  </>;
}

// Exporting your Default App Component
export default App

Step to Run Application: Run the application using the following command from the root directory of the project:

npm start

Output: Now open your browser and go to http://localhost:3000/, you will see the following output:

Example 2: Write down the following code in the App.js file. Here, App is our default component where we have written our code.

App.js

import React from 'react';
import TestRenderer from 'react-test-renderer';

// Defining our App Component
const App = () => {

  // Function to demonstrate TestRenderer.create() method
  function testRenderFun() {
    const renderer = TestRenderer.create(
      <div>GeeksforGeeks
      TestRenderer.create() method
      </div>
    );

    // Calling toJSON function to our rendered object
    console.log(renderer.toJSON());
  }

  // Function Call
  testRenderFun();

  // Returning our JSX code
  return <>
    <p>
      GeeksforGeeks TestRenderer.create() method
    </p>

  </>;
}

// Exporting your Default App Component
export default App

Step to Run Application: Run the application using the following command from the root directory of the project:

npm start

Output: Now open your browser and go to http://localhost:3000/, you will see the following output:

Reference: https://reactjs.org/docs/test-renderer.html#testrenderercreate