SchedulerPostTask-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
 * @jest-environment node
 */

/* eslint-disable no-for-of-loops/no-for-of-loops */

'use strict';

let Scheduler;
let runtime;
let performance;
let cancelCallback;
let scheduleCallback;
let ImmediatePriority;
let NormalPriority;
let UserBlockingPriority;
let LowPriority;
let IdlePriority;
let shouldYield;

// The Scheduler postTask implementation uses a new postTask browser API to
// schedule work on the main thread. This test suite mocks all browser methods
// used in our implementation. It assumes as little as possible about the order
// and timing of events.
describe('SchedulerPostTask', () => {
  beforeEach(() => {
    jest.resetModules();
    jest.mock('scheduler', () =>
      jest.requireActual('scheduler/unstable_post_task'),
    );

    runtime = installMockBrowserRuntime();
    performance = window.performance;
    Scheduler = require('scheduler');
    cancelCallback = Scheduler.unstable_cancelCallback;
    scheduleCallback = Scheduler.unstable_scheduleCallback;
    ImmediatePriority = Scheduler.unstable_ImmediatePriority;
    UserBlockingPriority = Scheduler.unstable_UserBlockingPriority;
    NormalPriority = Scheduler.unstable_NormalPriority;
    LowPriority = Scheduler.unstable_LowPriority;
    IdlePriority = Scheduler.unstable_IdlePriority;
    shouldYield = Scheduler.unstable_shouldYield;
  });

  afterEach(() => {
    if (!runtime.isLogEmpty()) {
      throw Error('Test exited without clearing log.');
    }
  });

  function installMockBrowserRuntime() {
    let taskQueue = new Map();
    let eventLog = [];

// ... (355 more lines)