How to use the sinon.useFakeTimers function in sinon

it("should generate a token", function() {
          // Reinit mockMQTTClientObject
          mockMQTTClientObject.reInitCommandCalled();
          mockMQTTClientObject.resetPublishedMessage();
          // Faking timer
          var clock = sinon.useFakeTimers();
          // Faking callback
          var fakeCallback = sinon.spy();
          // Init thingShadowClient
          var thingShadows = thingShadow( {
            keyPath:'test/data/private.pem.key',
            certPath:'test/data/certificate.pem.crt',
            caPath:'test/data/root-CA.crt',
            clientId:'dummy-client-1',
            host:'XXXX.iot.us-east-1.amazonaws.com'
          }, {  
            operationTimeout:1000 // Set operation timeout to be 1 sec
          } );
          // Register callback
          thingShadows.on('timeout', fakeCallback);
          // Register a thing
          thingShadows.register('testShadow3');

it('should provide minimum throughput', () => {
    let initialDate = new Date(2011, 9, 1).getTime();
    let clock = sinon.useFakeTimers(initialDate);
    let sampler = new GuaranteedThroughputSampler(2, 0);
    clock = sinon.useFakeTimers(initialDate + 20000);

    let expectedTags = { 'sampler.type': 'lowerbound', 'sampler.param': 0 };
    [true, true, false].forEach(expectedDecision => {
      let actualTags = {};
      let decision = sampler.isSampled('testOperationName', actualTags);
      // We asked for 2 traces per second and 0% probability for the rest.
      // Since the test runs under one second, we expect 2 successful samples
      // and one unsuccessful.
      if (expectedDecision) {
        assert.isTrue(decision, 'must sample');
        assert.deepEqual(expectedTags, actualTags);
      } else {
        assert.isFalse(decision, 'must not sample');
        assert.deepEqual({}, actualTags);

it('update balance', () => {
    let initialDate = new Date(2011, 9, 1).getTime();
    let clock = sinon.useFakeTimers(initialDate);
    let limiter = new RateLimiter(0.1, 1);
    assert.equal(
      true,
      limiter._balance <= 1 && limiter._balance >= 0,
      'balance should be initialized to a random value between [0:1]'
    );
    limiter._balance = 1.0;
    assert.equal(limiter.checkCredit(1), true, 'expected checkCredit to be true');

    limiter.update(0.1, 3);
    clock.restore();
    // move time 20s forward, enough to accumulate credits for 2 messages
    clock = sinon.useFakeTimers(initialDate + 20000);
    assert.equal(limiter.checkCredit(1), true, 'expected checkCredit to be true');
    assert.equal(limiter.checkCredit(1), true, 'expected checkCredit to be true');
    assert.equal(limiter.checkCredit(1), false, 'expected checkCredit to be false');

    // move time 30s forward, enough to accumulate credits for another message (should have
    // enough credits for 3 at this point)
    clock = sinon.useFakeTimers(initialDate + 50000);
    assert.equal(limiter.checkCredit(1), true, 'expected checkCredit to be true');
    assert.equal(limiter._balance, 2, 'balance should be at 2 after spending 1');

    // move time 5s forward, not enough to accumulate credits for another message
    clock = sinon.useFakeTimers(initialDate + 55000);
    // reduce the maxBalance so the limiter is capped at 1
    limiter.update(0.1, 1);
    assert.equal(limiter._balance, 2.5 / 3.0, 'balance should be proportional to the original range');
    assert.equal(limiter.checkCredit(1), false, 'expected checkCredit to be false');

it('should be able to dispatch actions from the other module', () => {
    const asyncTimeToDelay = 2000
    const timer = Sinon.useFakeTimers()
    @Module('Foo')
    class FooModule extends Ayanami<{ foo: string }> {
      defaultState = {
        foo: '1',
      }

      @Reducer()
      set(state: { foo: string }, payload: string) {
        return { ...state, foo: payload }
      }
    }

    @Module('Bar')
    class BarModule extends Ayanami<{}> {
      defaultState = {}

beforeEach(() => {
  clock = sinon.useFakeTimers();
});

beforeEach(function () {
        this.clock = sinon.useFakeTimers();
        reconstruct_fake_publish_engine();
    });

global.window = {
			addEventListener: sinon.stub(),
			parent: {
				postMessage: sinon.stub()
			}
		};
		global.document = {
			addEventListener: sinon.stub(),
			body: {
				scrollHeight: 100
			}
		};
		client = new Client({syncLang: false, syncTitle: false});
		sendEvent = sinon.stub(client, 'sendEvent');
		sendMessage = sinon.stub(client, '_sendMessage');
		clock = sinon.useFakeTimers();
	});

    before(() => clock = sinon.useFakeTimers());
    after(() => clock.restore());

beforeEach(function () {
        clock = sinon.useFakeTimers();
    });

beforeEach(function () {
    shipit = createShipitInstance();
    clock = sinon.useFakeTimers(1397730698075);
  });
  afterEach(function () {