describe('Clock', function() {
  const NODE_JS =
    typeof process !== 'undefined' &&
    process.versions &&
    typeof process.versions.node === 'string';

  it('does not replace setTimeout until it is installed', function() {
    const fakeSetTimeout = jasmine.createSpy('global setTimeout');
    const fakeGlobal = { setTimeout: fakeSetTimeout };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['scheduleFunction']
    );
    const delayedFn = jasmine.createSpy('delayedFn');
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    fakeGlobal.setTimeout(delayedFn, 0);

    expect(fakeSetTimeout).toHaveBeenCalledWith(delayedFn, 0);
    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();

    fakeSetTimeout.calls.reset();

    clock.install();
    fakeGlobal.setTimeout(delayedFn, 0);

    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalled();
    expect(fakeSetTimeout).not.toHaveBeenCalled();
  });

  it('does not replace clearTimeout until it is installed', function() {
    const fakeClearTimeout = jasmine.createSpy('global cleartimeout');
    const fakeGlobal = { clearTimeout: fakeClearTimeout };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['removeFunctionWithId']
    );
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    fakeGlobal.clearTimeout('foo');

    expect(fakeClearTimeout).toHaveBeenCalledWith('foo');
    expect(
      delayedFunctionScheduler.removeFunctionWithId
    ).not.toHaveBeenCalled();

    fakeClearTimeout.calls.reset();

    clock.install();
    fakeGlobal.clearTimeout('foo');

    expect(delayedFunctionScheduler.removeFunctionWithId).toHaveBeenCalled();
    expect(fakeClearTimeout).not.toHaveBeenCalled();
  });

  it('does not replace setInterval until it is installed', function() {
    const fakeSetInterval = jasmine.createSpy('global setInterval');
    const fakeGlobal = { setInterval: fakeSetInterval };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['scheduleFunction']
    );
    const delayedFn = jasmine.createSpy('delayedFn');
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    fakeGlobal.setInterval(delayedFn, 0);

    expect(fakeSetInterval).toHaveBeenCalledWith(delayedFn, 0);
    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();

    fakeSetInterval.calls.reset();

    clock.install();
    fakeGlobal.setInterval(delayedFn, 0);

    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalled();
    expect(fakeSetInterval).not.toHaveBeenCalled();
  });

  it('does not replace clearInterval until it is installed', function() {
    const fakeClearInterval = jasmine.createSpy('global clearinterval');
    const fakeGlobal = { clearInterval: fakeClearInterval };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['removeFunctionWithId']
    );
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    fakeGlobal.clearInterval('foo');

    expect(fakeClearInterval).toHaveBeenCalledWith('foo');
    expect(
      delayedFunctionScheduler.removeFunctionWithId
    ).not.toHaveBeenCalled();

    fakeClearInterval.calls.reset();

    clock.install();
    fakeGlobal.clearInterval('foo');

    expect(delayedFunctionScheduler.removeFunctionWithId).toHaveBeenCalled();
    expect(fakeClearInterval).not.toHaveBeenCalled();
  });

  it('does not install if the current setTimeout is not the original function on the global', function() {
    const originalFakeSetTimeout = function() {};
    const replacedSetTimeout = function() {};
    const fakeGlobal = { setTimeout: originalFakeSetTimeout };
    const delayedFunctionSchedulerFactory = jasmine.createSpy(
      'delayedFunctionSchedulerFactory'
    );
    const mockDate = {};
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      delayedFunctionSchedulerFactory,
      mockDate
    );

    fakeGlobal.setTimeout = replacedSetTimeout;

    expect(function() {
      clock.install();
    }).toThrowError(/unable to install/);

    expect(delayedFunctionSchedulerFactory).not.toHaveBeenCalled();
    expect(fakeGlobal.setTimeout).toBe(replacedSetTimeout);
  });

  it('does not install if the current clearTimeout is not the original function on the global', function() {
    const originalFakeClearTimeout = function() {};
    const replacedClearTimeout = function() {};
    const fakeGlobal = { clearTimeout: originalFakeClearTimeout };
    const delayedFunctionSchedulerFactory = jasmine.createSpy(
      'delayedFunctionSchedulerFactory'
    );
    const mockDate = {};
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      delayedFunctionSchedulerFactory,
      mockDate
    );

    fakeGlobal.clearTimeout = replacedClearTimeout;

    expect(function() {
      clock.install();
    }).toThrowError(/unable to install/);

    expect(delayedFunctionSchedulerFactory).not.toHaveBeenCalled();
    expect(fakeGlobal.clearTimeout).toBe(replacedClearTimeout);
  });

  it('does not install if the current setInterval is not the original function on the global', function() {
    const originalFakeSetInterval = function() {};
    const replacedSetInterval = function() {};
    const fakeGlobal = { setInterval: originalFakeSetInterval };
    const delayedFunctionSchedulerFactory = jasmine.createSpy(
      'delayedFunctionSchedulerFactory'
    );
    const mockDate = {};
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      delayedFunctionSchedulerFactory,
      mockDate
    );

    fakeGlobal.setInterval = replacedSetInterval;

    expect(function() {
      clock.install();
    }).toThrowError(/unable to install/);

    expect(delayedFunctionSchedulerFactory).not.toHaveBeenCalled();
    expect(fakeGlobal.setInterval).toBe(replacedSetInterval);
  });

  it('does not install if the current clearInterval is not the original function on the global', function() {
    const originalFakeClearInterval = function() {};
    const replacedClearInterval = function() {};
    const fakeGlobal = { clearInterval: originalFakeClearInterval };
    const delayedFunctionSchedulerFactory = jasmine.createSpy(
      'delayedFunctionSchedulerFactory'
    );
    const mockDate = {};
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      delayedFunctionSchedulerFactory,
      mockDate
    );

    fakeGlobal.clearInterval = replacedClearInterval;

    expect(function() {
      clock.install();
    }).toThrowError(/unable to install/);

    expect(delayedFunctionSchedulerFactory).not.toHaveBeenCalled();
    expect(fakeGlobal.clearInterval).toBe(replacedClearInterval);
  });

  it('restores the global timer functions on uninstall', function() {
    const fakeSetTimeout = jasmine.createSpy('global setTimeout');
    const fakeClearTimeout = jasmine.createSpy('global clearTimeout');
    const fakeSetInterval = jasmine.createSpy('global setInterval');
    const fakeClearInterval = jasmine.createSpy('global clearInterval');
    const fakeGlobal = {
      setTimeout: fakeSetTimeout,
      clearTimeout: fakeClearTimeout,
      setInterval: fakeSetInterval,
      clearInterval: fakeClearInterval
    };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['scheduleFunction', 'reset']
    );
    const delayedFn = jasmine.createSpy('delayedFn');
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();
    clock.uninstall();
    fakeGlobal.setTimeout(delayedFn, 0);
    fakeGlobal.clearTimeout('foo');
    fakeGlobal.setInterval(delayedFn, 10);
    fakeGlobal.clearInterval('bar');

    expect(fakeSetTimeout).toHaveBeenCalledWith(delayedFn, 0);
    expect(fakeClearTimeout).toHaveBeenCalledWith('foo');
    expect(fakeSetInterval).toHaveBeenCalledWith(delayedFn, 10);
    expect(fakeClearInterval).toHaveBeenCalledWith('bar');
    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();
  });

  it('can be installed for the duration of a passed in function and uninstalled when done', function() {
    const fakeSetTimeout = jasmine.createSpy('global setTimeout');
    const fakeClearTimeout = jasmine.createSpy('global clearTimeout');
    const fakeSetInterval = jasmine.createSpy('global setInterval');
    const fakeClearInterval = jasmine.createSpy('global clearInterval');
    const fakeGlobal = {
      setTimeout: fakeSetTimeout,
      clearTimeout: fakeClearTimeout,
      setInterval: fakeSetInterval,
      clearInterval: fakeClearInterval
    };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['scheduleFunction', 'reset', 'removeFunctionWithId']
    );
    const delayedFn = jasmine.createSpy('delayedFn');
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );
    let passedFunctionCalled = false;

    clock.withMock(function() {
      fakeGlobal.setTimeout(delayedFn, 0);
      fakeGlobal.clearTimeout('foo');
      fakeGlobal.setInterval(delayedFn, 10);
      fakeGlobal.clearInterval('bar');
      passedFunctionCalled = true;
    });

    expect(passedFunctionCalled).toBe(true);

    expect(fakeSetTimeout).not.toHaveBeenCalled();
    expect(fakeClearTimeout).not.toHaveBeenCalled();
    expect(fakeSetInterval).not.toHaveBeenCalled();
    expect(fakeClearInterval).not.toHaveBeenCalled();
    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalled();

    delayedFunctionScheduler.scheduleFunction.calls.reset();

    fakeGlobal.setTimeout(delayedFn, 0);
    fakeGlobal.clearTimeout('foo');
    fakeGlobal.setInterval(delayedFn, 10);
    fakeGlobal.clearInterval('bar');

    expect(fakeSetTimeout).toHaveBeenCalledWith(delayedFn, 0);
    expect(fakeClearTimeout).toHaveBeenCalledWith('foo');
    expect(fakeSetInterval).toHaveBeenCalledWith(delayedFn, 10);
    expect(fakeClearInterval).toHaveBeenCalledWith('bar');
    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();
  });

  it('can be installed for the duration of a passed in function and uninstalled if an error is thrown', function() {
    const fakeSetTimeout = jasmine.createSpy('global setTimeout');
    const fakeClearTimeout = jasmine.createSpy('global clearTimeout');
    const fakeSetInterval = jasmine.createSpy('global setInterval');
    const fakeClearInterval = jasmine.createSpy('global clearInterval');
    const fakeGlobal = {
      setTimeout: fakeSetTimeout,
      clearTimeout: fakeClearTimeout,
      setInterval: fakeSetInterval,
      clearInterval: fakeClearInterval
    };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['scheduleFunction', 'reset', 'removeFunctionWithId']
    );
    const delayedFn = jasmine.createSpy('delayedFn');
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );
    let passedFunctionCalled = false;

    expect(function() {
      clock.withMock(function() {
        fakeGlobal.setTimeout(delayedFn, 0);
        fakeGlobal.clearTimeout('foo');
        fakeGlobal.setInterval(delayedFn, 10);
        fakeGlobal.clearInterval('bar');
        passedFunctionCalled = true;
        throw 'oops';
      });
    }).toThrow('oops');

    expect(passedFunctionCalled).toBe(true);

    expect(fakeSetTimeout).not.toHaveBeenCalled();
    expect(fakeClearTimeout).not.toHaveBeenCalled();
    expect(fakeSetInterval).not.toHaveBeenCalled();
    expect(fakeClearInterval).not.toHaveBeenCalled();
    expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalled();

    delayedFunctionScheduler.scheduleFunction.calls.reset();

    fakeGlobal.setTimeout(delayedFn, 0);
    fakeGlobal.clearTimeout('foo');
    fakeGlobal.setInterval(delayedFn, 10);
    fakeGlobal.clearInterval('bar');

    expect(fakeSetTimeout).toHaveBeenCalledWith(delayedFn, 0);
    expect(fakeClearTimeout).toHaveBeenCalledWith('foo');
    expect(fakeSetInterval).toHaveBeenCalledWith(delayedFn, 10);
    expect(fakeClearInterval).toHaveBeenCalledWith('bar');
    expect(delayedFunctionScheduler.scheduleFunction).not.toHaveBeenCalled();
  });

  it('identifies its timing functions', function() {
    const fakeSetTimeout = jasmine.createSpy('global setTimeout');
    const fakeGlobal = { setTimeout: fakeSetTimeout };
    const delayedFunctionScheduler = jasmine.createSpyObj(
      'delayedFunctionScheduler',
      ['scheduleFunction']
    );
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      fakeGlobal,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );
    clock.install();

    expect(
      fakeGlobal.setTimeout[privateUnderTest.Clock.IsMockClockTimingFn]
    ).toEqual(true);
    expect(
      fakeGlobal.clearTimeout[privateUnderTest.Clock.IsMockClockTimingFn]
    ).toEqual(true);
    expect(
      fakeGlobal.setInterval[privateUnderTest.Clock.IsMockClockTimingFn]
    ).toEqual(true);
    expect(
      fakeGlobal.clearInterval[privateUnderTest.Clock.IsMockClockTimingFn]
    ).toEqual(true);
  });

  describe('setTimeout', function() {
    it('schedules the delayed function with the fake timer', function() {
      const fakeSetTimeout = jasmine.createSpy('setTimeout');
      const scheduleFunction = jasmine.createSpy('scheduleFunction');
      const delayedFunctionScheduler = { scheduleFunction: scheduleFunction };
      const fakeGlobal = { setTimeout: fakeSetTimeout };
      const delayedFn = jasmine.createSpy('delayedFn');
      const mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      const clock = new privateUnderTest.Clock(
        fakeGlobal,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );
      const timeout = new clock.FakeTimeout();

      clock.install();
      clock.setTimeout(delayedFn, 0, 'a', 'b');

      expect(fakeSetTimeout).not.toHaveBeenCalled();

      if (!NODE_JS) {
        expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(
          delayedFn,
          0,
          ['a', 'b']
        );
      } else {
        expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(
          delayedFn,
          0,
          ['a', 'b'],
          false,
          timeout
        );
      }
    });

    it('returns an id for the delayed function', function() {
      const fakeSetTimeout = jasmine.createSpy('setTimeout');
      const scheduleId = 123;
      const scheduleFunction = jasmine
        .createSpy('scheduleFunction')
        .and.returnValue(scheduleId);
      const delayedFunctionScheduler = { scheduleFunction: scheduleFunction };
      const fakeGlobal = { setTimeout: fakeSetTimeout };
      const delayedFn = jasmine.createSpy('delayedFn');
      const mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      const clock = new privateUnderTest.Clock(
        fakeGlobal,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );

      clock.install();
      const timeout = clock.setTimeout(delayedFn, 0);

      if (!NODE_JS) {
        expect(timeout).toEqual(123);
      } else {
        expect(timeout.constructor.name).toEqual('FakeTimeout');
      }
    });
  });

  describe('clearTimeout', function() {
    it('clears the scheduled function with the scheduler', function() {
      const fakeClearTimeout = jasmine.createSpy('clearTimeout');
      const delayedFunctionScheduler = jasmine.createSpyObj(
        'delayedFunctionScheduler',
        ['removeFunctionWithId']
      );
      const fakeGlobal = { setTimeout: fakeClearTimeout };
      const mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      const clock = new privateUnderTest.Clock(
        fakeGlobal,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );

      clock.install();
      clock.clearTimeout(123);

      expect(fakeClearTimeout).not.toHaveBeenCalled();
      expect(
        delayedFunctionScheduler.removeFunctionWithId
      ).toHaveBeenCalledWith(123);
    });
  });

  describe('setInterval', function() {
    it('schedules the delayed function with the fake timer', function() {
      const fakeSetInterval = jasmine.createSpy('setInterval');
      const scheduleFunction = jasmine.createSpy('scheduleFunction');
      const delayedFunctionScheduler = { scheduleFunction: scheduleFunction };
      const fakeGlobal = { setInterval: fakeSetInterval };
      const delayedFn = jasmine.createSpy('delayedFn');
      const mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      const clock = new privateUnderTest.Clock(
        fakeGlobal,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );
      const timeout = new clock.FakeTimeout();

      clock.install();
      clock.setInterval(delayedFn, 0, 'a', 'b');

      expect(fakeSetInterval).not.toHaveBeenCalled();

      if (!NODE_JS) {
        expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(
          delayedFn,
          0,
          ['a', 'b'],
          true
        );
      } else {
        expect(delayedFunctionScheduler.scheduleFunction).toHaveBeenCalledWith(
          delayedFn,
          0,
          ['a', 'b'],
          true,
          timeout
        );
      }
    });

    it('returns an id for the delayed function', function() {
      const fakeSetInterval = jasmine.createSpy('setInterval');
      const scheduleId = 123;
      const scheduleFunction = jasmine
        .createSpy('scheduleFunction')
        .and.returnValue(scheduleId);
      const delayedFunctionScheduler = { scheduleFunction: scheduleFunction };
      const fakeGlobal = { setInterval: fakeSetInterval };
      const delayedFn = jasmine.createSpy('delayedFn');
      const mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      const clock = new privateUnderTest.Clock(
        fakeGlobal,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );

      clock.install();
      const interval = clock.setInterval(delayedFn, 0);

      if (!NODE_JS) {
        expect(interval).toEqual(123);
      } else {
        expect(interval.constructor.name).toEqual('FakeTimeout');
      }
    });
  });

  describe('clearInterval', function() {
    it('clears the scheduled function with the scheduler', function() {
      const clearInterval = jasmine.createSpy('clearInterval');
      const delayedFunctionScheduler = jasmine.createSpyObj(
        'delayedFunctionScheduler',
        ['removeFunctionWithId']
      );
      const fakeGlobal = { setInterval: clearInterval };
      const mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      const clock = new privateUnderTest.Clock(
        fakeGlobal,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );

      clock.install();
      clock.clearInterval(123);

      expect(clearInterval).not.toHaveBeenCalled();
      expect(
        delayedFunctionScheduler.removeFunctionWithId
      ).toHaveBeenCalledWith(123);
    });
  });

  it('gives you a friendly reminder if the Clock is not installed and you tick', function() {
    const clock = new privateUnderTest.Clock(
      {},
      jasmine.createSpyObj('delayedFunctionScheduler', ['tick'])
    );
    expect(function() {
      clock.tick(50);
    }).toThrow();
  });
});

describe('Clock (acceptance)', function() {
  it('can run setTimeouts/setIntervals synchronously', function() {
    const delayedFn1 = jasmine.createSpy('delayedFn1');
    const delayedFn2 = jasmine.createSpy('delayedFn2');
    const delayedFn3 = jasmine.createSpy('delayedFn3');
    const recurring1 = jasmine.createSpy('recurring1');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setTimeout: setTimeout },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    clock.setTimeout(delayedFn1, 0);
    const intervalId = clock.setInterval(recurring1, 50);
    clock.setTimeout(delayedFn2, 100);
    clock.setTimeout(delayedFn3, 200);

    expect(delayedFn1).not.toHaveBeenCalled();
    expect(delayedFn2).not.toHaveBeenCalled();
    expect(delayedFn3).not.toHaveBeenCalled();

    clock.tick(0);

    expect(delayedFn1).toHaveBeenCalled();
    expect(delayedFn2).not.toHaveBeenCalled();
    expect(delayedFn3).not.toHaveBeenCalled();

    clock.tick(50);

    expect(recurring1).toHaveBeenCalled();
    expect(recurring1.calls.count()).toBe(1);
    expect(delayedFn2).not.toHaveBeenCalled();
    expect(delayedFn3).not.toHaveBeenCalled();

    clock.tick(50);

    expect(recurring1.calls.count()).toBe(2);
    expect(delayedFn2).toHaveBeenCalled();
    expect(delayedFn3).not.toHaveBeenCalled();

    clock.tick(100);

    expect(recurring1.calls.count()).toBe(4);
    expect(delayedFn3).toHaveBeenCalled();

    clock.clearInterval(intervalId);
    clock.tick(50);

    expect(recurring1.calls.count()).toBe(4);
  });

  describe('auto tick mode', () => {
    let delayedFunctionScheduler;
    let mockDate;
    let clock;

    beforeEach(() => {
      delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
      mockDate = {
        install: function() {},
        tick: function() {},
        uninstall: function() {}
      };
      // window setTimeout to window to make firefox happy
      const _setTimeout =
        typeof window !== 'undefined' ? setTimeout.bind(window) : setTimeout;
      // passing a fake global allows us to preserve the real timing functions for use in tests
      const _global = { setTimeout: _setTimeout, setInterval: setInterval };
      clock = new privateUnderTest.Clock(
        _global,
        function() {
          return delayedFunctionScheduler;
        },
        mockDate
      );
      clock.install().autoTick();
    });

    afterEach(() => {
      clock.uninstall();
    });

    it('flushes microtask queue between macrotasks', async () => {
      const log = [];
      await new Promise(r => clock.setTimeout(r, 10)).then(() => {
        log.push(1);
        Promise.resolve().then(() => log.push(2));
        Promise.resolve().then(() => log.push(3));
      });
      await new Promise(r => clock.setTimeout(r, 10)).then(() => {
        log.push(4);
        Promise.resolve().then(() => log.push(5));
      });
      expect(log).toEqual([1, 2, 3, 4, 5]);
    });

    it('can run setTimeouts/setIntervals asynchronously', function() {
      const recurring = jasmine.createSpy('recurring');
      const fn1 = jasmine.createSpy('fn1');
      const fn2 = jasmine.createSpy('fn2');
      const fn3 = jasmine.createSpy('fn3');

      const intervalId = clock.setInterval(recurring, 50);
      // In a microtask, add some timeouts.
      Promise.resolve()
        .then(function() {
          return new Promise(function(resolve) {
            clock.setTimeout(resolve, 25);
          });
        })
        .then(function() {
          fn1();
          return new Promise(function(resolve) {
            clock.setTimeout(resolve, 200);
          });
        })
        .then(function() {
          fn2();
          return new Promise(function(resolve) {
            clock.setTimeout(resolve, 100);
          });
        })
        .then(function() {
          fn3();
        });

      expect(recurring).not.toHaveBeenCalled();
      expect(fn1).not.toHaveBeenCalled();
      expect(fn2).not.toHaveBeenCalled();
      expect(fn3).not.toHaveBeenCalled();

      return new Promise(resolve => clock.setTimeout(resolve, 50))
        .then(function() {
          expect(recurring).toHaveBeenCalledTimes(1);
          expect(fn1).toHaveBeenCalled();
          expect(fn2).not.toHaveBeenCalled();
          expect(fn3).not.toHaveBeenCalled();

          return new Promise(resolve => clock.setTimeout(resolve, 175));
        })
        .then(function() {
          expect(recurring).toHaveBeenCalledTimes(4);
          expect(fn1).toHaveBeenCalled();
          expect(fn2).toHaveBeenCalled();
          expect(fn3).not.toHaveBeenCalled();

          clock.clearInterval(intervalId);
          return new Promise(resolve => clock.setTimeout(resolve, 100));
        })
        .then(function() {
          expect(recurring).toHaveBeenCalledTimes(4);
          expect(fn1).toHaveBeenCalled();
          expect(fn2).toHaveBeenCalled();
          expect(fn3).toHaveBeenCalled();
        });
    });

    it('aborts auto ticking when uninstalled, even if installed again synchonrously', async () => {
      clock.uninstall();
      clock.install();

      let resolved = false;
      const promise = new Promise(resolve => {
        clock.setTimeout(resolve, 1);
      }).then(() => {
        resolved = true;
      });

      // wait some real time and verify that the clock did not flush the timer above automatically
      await new Promise(resolve => setTimeout(resolve, 2));
      expect(resolved).toBe(false);

      // enabling auto tick again will flush the timer
      clock.autoTick();
      await expectAsync(promise).toBeResolved();
    });

    it('speeds up the execution of the timers in all browsers', async () => {
      const startTimeMs = performance.now() / 1000;
      await new Promise(resolve => clock.setTimeout(resolve, 5000));
      await new Promise(resolve => clock.setTimeout(resolve, 5000));
      await new Promise(resolve => clock.setTimeout(resolve, 5000));
      await new Promise(resolve => clock.setTimeout(resolve, 5000));
      const endTimeMs = performance.now() / 1000;
      // Ensure we didn't take 20s to complete the awaits above and, in fact, can do it in a fraction of a second
      expect(endTimeMs - startTimeMs).toBeLessThan(100);
    });

    it('is easy to test async functions with interleaved timers and microtasks', async () => {
      async function blackBoxWithLotsOfAsyncStuff() {
        await new Promise(r => clock.setTimeout(r, 10));
        await Promise.resolve();
        await Promise.resolve();
        await new Promise(r => clock.setTimeout(r, 20));
        await Promise.resolve();
        await Promise.resolve();
        await Promise.resolve();
        return 'done';
      }
      const result = await blackBoxWithLotsOfAsyncStuff();
      expect(result).toBe('done');
    });
  });

  it('can clear a previously set timeout', function() {
    const clearedFn = jasmine.createSpy('clearedFn');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setTimeout: function() {} },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    const timeoutId = clock.setTimeout(clearedFn, 100);
    expect(clearedFn).not.toHaveBeenCalled();

    clock.clearTimeout(timeoutId);
    clock.tick(100);

    expect(clearedFn).not.toHaveBeenCalled();
  });

  it("can clear a previously set interval using that interval's handler", function() {
    const spy = jasmine.createSpy('spy');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setInterval: function() {} },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    const intervalId = clock.setInterval(function() {
      spy();
      clock.clearInterval(intervalId);
    }, 100);
    clock.tick(200);

    expect(spy.calls.count()).toEqual(1);
  });

  it('correctly schedules functions after the Clock has advanced', function() {
    const delayedFn1 = jasmine.createSpy('delayedFn1');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setTimeout: function() {} },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    clock.tick(100);
    clock.setTimeout(delayedFn1, 10, ['some', 'arg']);
    clock.tick(5);
    expect(delayedFn1).not.toHaveBeenCalled();
    clock.tick(5);
    expect(delayedFn1).toHaveBeenCalled();
  });

  it('correctly schedules functions while the Clock is advancing', function() {
    const delayedFn1 = jasmine.createSpy('delayedFn1');
    const delayedFn2 = jasmine.createSpy('delayedFn2');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setTimeout: function() {} },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    delayedFn1.and.callFake(function() {
      clock.setTimeout(delayedFn2, 0);
    });
    clock.install();
    clock.setTimeout(delayedFn1, 5);

    clock.tick(5);
    expect(delayedFn1).toHaveBeenCalled();
    expect(delayedFn2).not.toHaveBeenCalled();

    clock.tick();
    expect(delayedFn2).toHaveBeenCalled();
  });

  it('correctly calls functions scheduled while the Clock is advancing', function() {
    const delayedFn1 = jasmine.createSpy('delayedFn1');
    const delayedFn2 = jasmine.createSpy('delayedFn2');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setTimeout: function() {} },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    delayedFn1.and.callFake(function() {
      clock.setTimeout(delayedFn2, 1);
    });
    clock.install();
    clock.setTimeout(delayedFn1, 5);

    clock.tick(6);
    expect(delayedFn1).toHaveBeenCalled();
    expect(delayedFn2).toHaveBeenCalled();
  });

  it('correctly schedules functions scheduled while the Clock is advancing but after the Clock is uninstalled', function() {
    const delayedFn1 = jasmine.createSpy('delayedFn1');
    const delayedFn2 = jasmine.createSpy('delayedFn2');
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const mockDate = {
      install: function() {},
      tick: function() {},
      uninstall: function() {}
    };
    const clock = new privateUnderTest.Clock(
      { setTimeout: function() {} },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    delayedFn1.and.callFake(function() {
      clock.uninstall();
      clock.install();
      clock.setTimeout(delayedFn2, 0);
    });

    clock.install();
    clock.setTimeout(delayedFn1, 1);

    clock.tick(1);
    expect(delayedFn1).toHaveBeenCalled();
    expect(delayedFn2).not.toHaveBeenCalled();

    clock.tick(1);
    expect(delayedFn2).toHaveBeenCalled();
  });

  it('does not mock the Date object by default', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      { setTimeout: setTimeout },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    expect(global.Date).toEqual(Date);

    const now = new global.Date().getTime();

    clock.tick(50);

    expect(new global.Date().getTime() - now).not.toEqual(50);
  });

  it('mocks the Date object and sets it to current time', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      { setTimeout: setTimeout },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install().mockDate();

    const now = new global.Date().getTime();

    clock.tick(50);

    expect(new global.Date().getTime() - now).toEqual(50);

    let timeoutDate = 0;
    clock.setTimeout(function() {
      timeoutDate = new global.Date().getTime();
    }, 100);

    clock.tick(100);

    expect(timeoutDate - now).toEqual(150);
  });

  it('mocks the Date object and sets it to a given time', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      { setTimeout: setTimeout },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );
    const baseTime = new Date(2013, 9, 23);

    clock.install().mockDate(baseTime);

    const now = new global.Date().getTime();

    expect(now).toEqual(baseTime.getTime());

    clock.tick(50);

    expect(new global.Date().getTime()).toEqual(baseTime.getTime() + 50);

    let timeoutDate = 0;
    clock.setTimeout(function() {
      timeoutDate = new global.Date().getTime();
    }, 100);

    clock.tick(100);

    expect(timeoutDate).toEqual(baseTime.getTime() + 150);
  });

  it('throws mockDate is called with a non-Date', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      { setTimeout: setTimeout },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    expect(() => clock.mockDate(12345)).toThrowError(
      'The argument to jasmine.clock().mockDate(), if specified, should be ' +
        'a Date instance.'
    );
  });

  it('mocks the Date object and updates the date per delayed function', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      { setTimeout: setTimeout },
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );
    const baseTime = new Date();

    clock.install().mockDate(baseTime);

    const actualTimes = [];
    const pushCurrentTime = function() {
      actualTimes.push(global.Date().getTime());
    };
    delayedFunctionScheduler.scheduleFunction(pushCurrentTime);
    delayedFunctionScheduler.scheduleFunction(pushCurrentTime, 1);
    delayedFunctionScheduler.scheduleFunction(pushCurrentTime, 3);

    clock.tick(1);
    expect(global.Date().getTime()).toEqual(baseTime.getTime() + 1);

    clock.tick(3);
    expect(global.Date().getTime()).toEqual(baseTime.getTime() + 4);

    clock.tick(1);
    expect(global.Date().getTime()).toEqual(baseTime.getTime() + 5);

    expect(actualTimes).toEqual([
      baseTime.getTime(),
      baseTime.getTime() + 1,
      baseTime.getTime() + 3
    ]);
  });

  it('correctly clears a scheduled timeout while the Clock is advancing', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date, setTimeout: undefined };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      global,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    let timerId2;

    global.setTimeout(function() {
      global.clearTimeout(timerId2);
    }, 100);

    timerId2 = global.setTimeout(fail, 100);

    clock.tick(100);
  });

  it('correctly clears a scheduled interval while the Clock is advancing', function() {
    const delayedFunctionScheduler = new privateUnderTest.DelayedFunctionScheduler();
    const global = { Date: Date, setTimeout: undefined };
    const mockDate = new privateUnderTest.MockDate(global);
    const clock = new privateUnderTest.Clock(
      global,
      function() {
        return delayedFunctionScheduler;
      },
      mockDate
    );

    clock.install();

    let timerId2;
    global.setInterval(function() {
      global.clearInterval(timerId2);
    }, 100);

    timerId2 = global.setInterval(fail, 100);

    clock.tick(400);
  });

  describe('Warning about monkey patching', function() {
    for (const name of ['tick', 'mockDate', 'install', 'uninstall']) {
      it(`warns if Clock#${name} is monkey patched`, function() {
        spyOn(console, 'error');
        const clock = new privateUnderTest.Clock({}, function() {}, {});
        const patch = {};
        clock[name] = patch;

        // eslint-disable-next-line no-console
        expect(console.error).toHaveBeenCalledOnceWith(
          jasmine.stringContaining('DEPRECATION: Monkey patching detected.')
        );
        // eslint-disable-next-line no-console
        expect(console.error).toHaveBeenCalledOnceWith(
          jasmine.stringContaining('ClockSpec.js')
        );
        expect(clock[name]).toBe(patch);
      });
    }
  });
});