Clock.js

getJasmineRequireObj().Clock = function() {
  function Clock(global, delayedFunctionScheduler, mockDate) {
    var self = this,
      realTimingFunctions = {
        setTimeout: global.setTimeout,
        clearTimeout: global.clearTimeout,
        setInterval: global.setInterval,
        clearInterval: global.clearInterval
      },
      fakeTimingFunctions = {
        setTimeout: setTimeout,
        clearTimeout: clearTimeout,
        setInterval: setInterval,
        clearInterval: clearInterval
      },
      installed = false,
      timer;


    self.install = function() {
      replace(global, fakeTimingFunctions);
      timer = fakeTimingFunctions;
      installed = true;

      return self;
    };

    self.uninstall = function() {
      delayedFunctionScheduler.reset();
      mockDate.uninstall();
      replace(global, realTimingFunctions);

      timer = realTimingFunctions;
      installed = false;
    };

    self.mockDate = function(initialDate) {
      mockDate.install(initialDate);
    };

    self.setTimeout = function(fn, delay, params) {
      if (legacyIE()) {
        if (arguments.length > 2) {
          throw new Error('IE < 9 cannot support extra params to setTimeout without a polyfill');
        }
        return timer.setTimeout(fn, delay);
      }
      return Function.prototype.apply.apply(timer.setTimeout, [global, arguments]);
    };

    self.setInterval = function(fn, delay, params) {
      if (legacyIE()) {
        if (arguments.length > 2) {
          throw new Error('IE < 9 cannot support extra params to setInterval without a polyfill');
        }
        return timer.setInterval(fn, delay);
      }
      return Function.prototype.apply.apply(timer.setInterval, [global, arguments]);
    };

    self.clearTimeout = function(id) {
      return Function.prototype.call.apply(timer.clearTimeout, [global, id]);
    };

    self.clearInterval = function(id) {
      return Function.prototype.call.apply(timer.clearInterval, [global, id]);
    };

    self.tick = function(millis) {
      if (installed) {
        mockDate.tick(millis);
        delayedFunctionScheduler.tick(millis);
      } else {
        throw new Error('Mock clock is not installed, use jasmine.clock().install()');
      }
    };

    return self;

    function legacyIE() {

if these methods are polyfilled, apply will be present

      return !(realTimingFunctions.setTimeout || realTimingFunctions.setInterval).apply;
    }

    function replace(dest, source) {
      for (var prop in source) {
        dest[prop] = source[prop];
      }
    }

    function setTimeout(fn, delay) {
      return delayedFunctionScheduler.scheduleFunction(fn, delay, argSlice(arguments, 2));
    }

    function clearTimeout(id) {
      return delayedFunctionScheduler.removeFunctionWithId(id);
    }

    function setInterval(fn, interval) {
      return delayedFunctionScheduler.scheduleFunction(fn, interval, argSlice(arguments, 2), true);
    }

    function clearInterval(id) {
      return delayedFunctionScheduler.removeFunctionWithId(id);
    }

    function argSlice(argsObj, n) {
      return Array.prototype.slice.call(argsObj, n);
    }
  }

  return Clock;
};