Mock setTimeout jest

MyController.js

exports.foo = (req, res) => {
  const isSuccess = Math.random() < 0.5;

  setTimeout(() => {
    if (isSuccess) {
      return res.send(201);
    }

    res.send(403);
  }, 3000);
};

MyController.test.js

const controller = require("./MyController");

function mockGlobalFunc(funcName, funcMock) {
  const funcOriginal = global[funcName];
  global[funcName] = funcMock;

  return () => {
    global[funcName] = funcOriginal;
  }
}

const setTimeoutRestoreFunction = mockGlobalFunc('setTimeout', callback => callback());

describe("controller", () => {
  afterAll(() => {
    setTimeoutRestoreFunction();
  });

  describe("controller.finish", () => {
    it("success response", async () => {
      jest.spyOn(global.Math, 'random').mockReturnValueOnce(0.12);

      const fakeResponse = {
        send: jest.fn(),
      };

      cartController.foo(undefined, fakeResponse);

      expect(fakeResponse.send).toHaveBeenCalledWith(201);
    });

    it("error response", async () => {
      jest.spyOn(global.Math, 'random').mockReturnValueOnce(0.60);

      const fakeResponse = {
        send: jest.fn(),
      };

      cartController.foo(undefined, fakeResponse);

      expect(fakeResponse.send).toHaveBeenCalledWith(403);
    });
  });
});