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/** @jest-environment jsdom */import { cancelCallback, requestCallback } from "../src";import "./MessageChannel";
describe("requestCallback basics", () => {  test("queue a task", done => {    requestCallback(() => {      done();    });  });
  test("queue a task in correct order", done => {    let count = 0;    requestCallback(() => {      expect(count).toBe(2);      done();    });    requestCallback(      () => {        count++;        expect(count).toBe(1);      },      { timeout: 10 }    );    requestCallback(      () => {        count++;        expect(count).toBe(2);      },      { timeout: 40 }    );  });
  test("supports cancelling a callback", done => {    const task = requestCallback(() => { done(new Error('should not be called')) });    cancelCallback(task);    requestCallback(done);  });
});