ReactCreateElement-test.js — react Source File

Source Code

/**
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @emails react-core
 */

'use strict';

let act;

let React;
let ReactDOMClient;
let assertConsoleErrorDev;
let assertConsoleWarnDev;

// NOTE: This module tests the old, "classic" JSX runtime, React.createElement.
// Do not use JSX syntax in this module; call React.createElement directly.
describe('ReactCreateElement', () => {
  let ComponentClass;

  beforeEach(() => {
    jest.resetModules();

    ({
      act,
      assertConsoleErrorDev,
      assertConsoleWarnDev,
    } = require('internal-test-utils'));

    React = require('react');
    ReactDOMClient = require('react-dom/client');
    ComponentClass = class extends React.Component {
      render() {
        return React.createElement('div');
      }
    };
  });

  it('returns a complete element according to spec', () => {
    const element = React.createElement(ComponentClass);
    expect(element.type).toBe(ComponentClass);
    expect(element.key).toBe(null);
    expect(element.ref).toBe(null);
    if (__DEV__) {
      expect(Object.isFrozen(element)).toBe(true);
      expect(Object.isFrozen(element.props)).toBe(true);
    }
    expect(element.props).toEqual({});
  });

  it('should warn when `key` is being accessed on composite element', async () => {
    class Child extends React.Component {
      render() {
        return React.createElement('div', null, this.props.key);
      }
    }
    class Parent extends React.Component {
// ... (385 more lines)