(function() {

  QUnit.module('fabric.util');

  function K (x) { return x }

  function _createImageElement() {
    return fabric.isLikelyNode ? new (require('canvas').Image) : fabric.document.createElement('img');
  }

  function getAbsolutePath(path) {
    var isAbsolute = /^https?:/.test(path);
    if (isAbsolute) return path;
    var imgEl = _createImageElement();
    imgEl.src = path;
    var src = imgEl.src;
    imgEl = null;
    return src;
  }

  var IMG_URL = fabric.isLikelyNode
    ? require("path").join(__dirname, '../fixtures/', 'very_large_image.jpg')
    : getAbsolutePath('../fixtures/very_large_image.jpg');

  test('fabric.util.toFixed', function(){
    ok(typeof fabric.util.toFixed == 'function');

    function test(what) {
      equal(fabric.util.toFixed(what, 2), 166.67, 'should leave 2 fractional digits');
      equal(fabric.util.toFixed(what, 5), 166.66667, 'should leave 5 fractional digits');
      equal(fabric.util.toFixed(what, 0), 167, 'should leave 0 fractional digits');

      var fractionless = (typeof what == 'number')
        ? parseInt(what)
        : what.substring(0, what.indexOf('.'));

      equal(fabric.util.toFixed(fractionless, 2), 166, 'should leave fractionless number as is');
    }

    test.call(this, '166.66666666666666666666'); // string
    test.call(this, 166.66666666666666666666); // number
  });

  test('fabric.util.removeFromArray', function() {
    var testArray = [1,2,3,4,5];

    ok(typeof fabric.util.removeFromArray == 'function');

    fabric.util.removeFromArray(testArray, 2);
    deepEqual([1,3,4,5], testArray);
    equal(fabric.util.removeFromArray(testArray, 1), testArray, 'should return reference to original array');

    testArray = [1,2,3,1];
    fabric.util.removeFromArray(testArray, 1);
    deepEqual([2,3,1], testArray, 'only first occurance of value should be deleted');

    testArray = [1,2,3];
    fabric.util.removeFromArray(testArray, 12);
    deepEqual([1,2,3], testArray, 'deleting unexistent value should not affect array');

    testArray = [];
    fabric.util.removeFromArray(testArray, 1);
    deepEqual([], testArray, 'deleting any value from empty array should not affect it');

    testArray = ['0'];
    fabric.util.removeFromArray(testArray, 0);
    deepEqual(['0'], testArray, 'should use (strict) identity comparison, rather than equality one');
  });

  test('fabric.util.degreesToRadians', function(){
    ok(typeof fabric.util.degreesToRadians == 'function');
    equal(fabric.util.degreesToRadians(0), 0);
    equal(fabric.util.degreesToRadians(90), Math.PI / 2);
    equal(fabric.util.degreesToRadians(180), Math.PI);

    deepEqual(fabric.util.degreesToRadians(), NaN);
  });

  test('fabric.util.getRandomInt', function() {
    ok(typeof fabric.util.getRandomInt == 'function');

    var randomInts = [];
    for (var i = 100; i--; ) {
      var randomInt = fabric.util.getRandomInt(100, 200);
      randomInts.push(randomInt);
      ok(randomInt >= 100 && randomInt <= 200);
    }

    var areAllTheSame = randomInts.every(function(value){
      return value === randomInts[0];
    });

    ok(!areAllTheSame);
  });

  test('fabric.util.falseFunction', function() {
    ok(typeof fabric.util.falseFunction == 'function');
    equal(fabric.util.falseFunction(), false);
  });

  test('String.prototype.trim', function() {
    ok(typeof String.prototype.trim == 'function');
    equal('\t\n   foo bar \n    \xA0  '.trim(), 'foo bar');
  });

  test('fabric.util.string.camelize', function() {
    var camelize = fabric.util.string.camelize;

    ok(typeof camelize == 'function');

    equal(camelize('foo'), 'foo');
    equal(camelize('foo-bar'), 'fooBar');
    equal(camelize('Foo-bar-Baz'), 'FooBarBaz');
    equal(camelize('FooBarBaz'), 'FooBarBaz');
    equal(camelize('-bar'), 'Bar');
    equal(camelize(''), '');
    equal(camelize('and_something_with_underscores'), 'and_something_with_underscores');
    equal(camelize('underscores_and-dashes'), 'underscores_andDashes');
    equal(camelize('--double'), 'Double');
  });

  test('fabric.util.string.escapeXml', function() {
    var escapeXml = fabric.util.string.escapeXml;

    ok(typeof escapeXml == 'function');

    // borrowed from Prototype.js
    equal('foo bar', escapeXml('foo bar'));
    equal('foo &lt;span&gt;bar&lt;/span&gt;', escapeXml('foo <span>bar</span>'));
    equal('foo ß bar', escapeXml('foo ß bar'));

    equal('ウィメンズ2007\nクルーズコレクション', escapeXml('ウィメンズ2007\nクルーズコレクション'));

    equal('a&lt;a href=&quot;blah&quot;&gt;blub&lt;/a&gt;b&lt;span&gt;&lt;div&gt;&lt;/div&gt;&lt;/span&gt;cdef&lt;strong&gt;!!!!&lt;/strong&gt;g',
          escapeXml('a<a href="blah">blub</a>b<span><div></div></span>cdef<strong>!!!!</strong>g'));

    equal('1\n2', escapeXml('1\n2'));
  });

  test('fabric.util.string.capitalize', function() {
    var capitalize = fabric.util.string.capitalize;

    ok(typeof capitalize == 'function');

    equal(capitalize('foo'), 'Foo');
    equal(capitalize(''), '');
    equal(capitalize('Foo'), 'Foo');
    equal(capitalize('foo-bar-baz'), 'Foo-bar-baz');
    equal(capitalize('FOO'), 'Foo');
    equal(capitalize('FoobaR'), 'Foobar');
    equal(capitalize('2foo'), '2foo');
  });

  test('fabric.util.object.extend', function() {
    var extend = fabric.util.object.extend;

    ok(typeof extend == 'function');

    var destination = { x: 1 },
        source = { y: 2 };

    extend(destination, source);

    equal(destination.x, 1);
    equal(destination.y, 2);
    equal(source.x, undefined);
    equal(source.y, 2);

    destination = { x: 1 };
    source = { x: 2 };

    extend(destination, source);

    equal(destination.x, 2);
    equal(source.x, 2);
  });

  test('fabric.util.object.clone', function() {
    var clone = fabric.util.object.clone;

    ok(typeof clone == 'function');

    var obj = { x: 1, y: [1, 2, 3] },
        clone = clone(obj);

    equal(clone.x, 1);
    notEqual(obj, clone);
    equal(clone.y, obj.y);
  });

  test('Function.prototype.bind', function() {
    ok(typeof Function.prototype.bind == 'function');

    var obj = { };
    function fn() {
      return [this, arguments[0], arguments[1]];
    }

    var bound = fn.bind(obj);
    deepEqual([obj, undefined, undefined], bound());
    deepEqual([obj, 1, undefined], bound(1))
    deepEqual([obj, 1, null], bound(1, null));

    bound = fn.bind(obj, 1);
    deepEqual([obj, 1, undefined], bound());
    deepEqual([obj, 1, 2], bound(2));

    function Point(x, y) {
      this.x = x;
      this.y = y;
    }

    var obj = { }
    var YAxisPoint = Point.bind(obj, 0);
    var axisPoint = new YAxisPoint(5);

    deepEqual(0, axisPoint.x);
    deepEqual(5, axisPoint.y);

    ok(axisPoint instanceof Point);
    // ok(axisPoint instanceof YAxisPoint); <-- fails
  });

  test('fabric.util.getById', function() {
    ok(typeof fabric.util.getById == 'function');

    var el = fabric.document.createElement('div');
    el.id = 'foobarbaz';
    fabric.document.body.appendChild(el);

    equal(el, fabric.util.getById(el));
    equal(el, fabric.util.getById('foobarbaz'));
    equal(null, fabric.util.getById('likely-non-existent-id'));
  });

  test('fabric.util.toArray', function() {
    ok(typeof fabric.util.toArray == 'function');

    deepEqual(['x', 'y'], fabric.util.toArray({ 0: 'x', 1: 'y', length: 2 }));
    deepEqual([1, 3], fabric.util.toArray(function(){ return arguments }(1, 3)));

    var nodelist = fabric.document.getElementsByTagName('div'),
        converted = fabric.util.toArray(nodelist);

    ok(converted instanceof Array);
    equal(nodelist.length, converted.length);
    equal(nodelist[0], converted[0]);
    equal(nodelist[1], converted[1]);
  });

  test('fabric.util.makeElement', function() {
    var makeElement = fabric.util.makeElement;
    ok(typeof makeElement == 'function');

    var el = makeElement('div');

    equal(el.tagName.toLowerCase(), 'div');
    equal(el.nodeType, 1);

    el = makeElement('p', { 'class': 'blah', 'for': 'boo_hoo', 'some_random-attribute': 'woot' });

    equal(el.tagName.toLowerCase(), 'p');
    equal(el.nodeType, 1);
    equal(el.className, 'blah');
    equal(el.htmlFor, 'boo_hoo');
    equal(el.getAttribute('some_random-attribute'), 'woot');
  });

  test('fabric.util.addClass', function() {
    var addClass = fabric.util.addClass;
    ok(typeof addClass == 'function');

    var el = fabric.document.createElement('div');
    addClass(el, 'foo');
    equal(el.className, 'foo');

    addClass(el, 'bar');
    equal(el.className, 'foo bar');

    addClass(el, 'baz qux');
    equal(el.className, 'foo bar baz qux');

    addClass(el, 'foo');
    equal(el.className, 'foo bar baz qux');
  });

  test('fabric.util.wrapElement', function() {
    var wrapElement = fabric.util.wrapElement;
    ok(typeof wrapElement == 'function');

    var el = fabric.document.createElement('p');
    var wrapper = wrapElement(el, 'div');

    equal(wrapper.tagName.toLowerCase(), 'div');
    equal(wrapper.firstChild, el);

    el = fabric.document.createElement('p');
    wrapper = wrapElement(el, 'div', { 'class': 'foo' });

    equal(wrapper.tagName.toLowerCase(), 'div');
    equal(wrapper.firstChild, el);
    equal(wrapper.className, 'foo');

    var childEl = fabric.document.createElement('span');
    var parentEl = fabric.document.createElement('p');

    parentEl.appendChild(childEl);

    wrapper = wrapElement(childEl, 'strong');

    // wrapper is now in between parent and child
    equal(wrapper.parentNode, parentEl);
    equal(wrapper.firstChild, childEl);
  });

  test('fabric.util.makeElementUnselectable', function() {
    var makeElementUnselectable = fabric.util.makeElementUnselectable;

    ok(typeof makeElementUnselectable == 'function');

    var el = fabric.document.createElement('p');
    el.appendChild(fabric.document.createTextNode('foo'));

    equal(el, makeElementUnselectable(el), 'should be "chainable"');
    if (typeof el.onselectstart != 'undefined') {
      equal(el.onselectstart, fabric.util.falseFunction);
    }

    // not sure if it's a good idea to test implementation details here
    // functional test would probably make more sense
    if (typeof el.unselectable == 'string') {
      equal('on', el.unselectable);
    }
    else if (typeof el.userSelect != 'undefined') {
      equal('none', el.userSelect);
    }
  });

  test('fabric.util.makeElementSelectable', function() {
    var makeElementSelectable = fabric.util.makeElementSelectable,
        makeElementUnselectable = fabric.util.makeElementUnselectable;

    ok(typeof makeElementSelectable == 'function');

    var el = fabric.document.createElement('p');
    el.appendChild(fabric.document.createTextNode('foo'));

    makeElementUnselectable(el);
    makeElementSelectable(el);

    if (typeof el.onselectstart != 'undefined') {
      equal(el.onselectstart, null);
    }
    if (typeof el.unselectable == 'string') {
      equal('', el.unselectable);
    }
    else if (typeof el.userSelect != 'undefined') {
      equal('', el.userSelect);
    }
  });

  test('fabric.loadSVGFromURL', function() {
    equal("function", typeof fabric.loadSVGFromURL);
  });

  var SVG_DOC_AS_STRING = '<?xml version="1.0"?>\
    <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\
    <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">\
      <polygon fill="red" stroke="blue" stroke-width="10" points="350, 75 379,161 469,161\
        397,215 423,301 350,250 277,301 303,215 231,161 321,161" />\
    </svg>';

  asyncTest('fabric.loadSVGFromString', function() {
    equal("function", typeof fabric.loadSVGFromString);

    var loadedObjects = [ ];
    fabric.loadSVGFromString(SVG_DOC_AS_STRING, function(objects) {
      loadedObjects = objects;
    });

    setTimeout(function() {
      ok(loadedObjects[0] instanceof fabric.Polygon);
      equal('red', loadedObjects[0].fill);
      start();
    }, 1000);
  });

  asyncTest('fabric.loadSVGFromString with surrounding whitespace', function() {
    var loadedObjects = [ ];
    fabric.loadSVGFromString('   \n\n  ' + SVG_DOC_AS_STRING + '  ', function(objects) {
      loadedObjects = objects;
    });

    setTimeout(function() {
      ok(loadedObjects[0] instanceof fabric.Polygon);
      equal('red', loadedObjects[0] && loadedObjects[0].fill);
      start();
    }, 1000);
  });

  asyncTest('fabric.util.loadImage', function() {
    ok(typeof fabric.util.loadImage == 'function');

    var callbackInvoked = false,
        objectPassedToCallback;

    if (IMG_URL.indexOf('/home/travis') === 0) {
      // image can not be accessed on travis so we're returning early
      start();
      return;
    }

    fabric.util.loadImage(IMG_URL, function(obj) {
      callbackInvoked = true;
      objectPassedToCallback = obj;
    });

    setTimeout(function() {
      ok(callbackInvoked, 'callback should be invoked');

      if (objectPassedToCallback) {
        var oImg = new fabric.Image(objectPassedToCallback);
        ok(/fixtures\/very_large_image\.jpg$/.test(oImg.getSrc()), 'image should have correct src');
      }

      start();
    }, 2000);
  });

  var SVG_WITH_1_ELEMENT = '<?xml version="1.0"?>\
    <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\
    <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">\
      <polygon fill="red" stroke="blue" stroke-width="10" points="350, 75 379,161 469,161\
        397,215 423,301 350,250 277,301 303,215 231,161 321,161" />\
    </svg>';

  var SVG_WITH_2_ELEMENTS = '<?xml version="1.0"?>\
    <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\
    <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">\
      <polygon fill="red" stroke="blue" stroke-width="10" points="350, 75 379,161 469,161\
        397,215 423,301 350,250 277,301 303,215 231,161 321,161" />\
      <polygon fill="red" stroke="blue" stroke-width="10" points="350, 75 379,161 469,161\
        397,215 423,301 350,250 277,301 303,215 231,161 321,161" />\
    </svg>';

  asyncTest('fabric.util.groupSVGElements', function() {
    ok(typeof fabric.util.groupSVGElements == 'function');

    var group1, group2;
    fabric.loadSVGFromString(SVG_WITH_1_ELEMENT, function(objects, options) {
      group1 = fabric.util.groupSVGElements(objects, options);
    });
    fabric.loadSVGFromString(SVG_WITH_2_ELEMENTS, function(objects, options) {
      group2 = fabric.util.groupSVGElements(objects, options);
    });

    setTimeout(function() {
      ok(group1 instanceof fabric.Polygon);
      ok(group2 instanceof fabric.PathGroup);
      start();
    }, 1000);
  });

  test('Array.prototype.indexOf', function() {

    // borrowed from Prototype.js
    equal(-1, [].indexOf(1));
    equal(-1, [0].indexOf(1));
    equal(0, [1].indexOf(1));
    equal(1, [0,1,2].indexOf(1));
    equal(0, [1,2,1].indexOf(1));
    equal(2, [1,2,1].indexOf(1, -1));
    equal(1, [undefined,null].indexOf(null));

    // ES5 compatibility tests.
    var undef;
    var array = [1, 2, 3, 4, 5, undef, 6, 7, 1, 2, 3];

    equal(2, array.indexOf(3, -47), "large negative value for fromIndex");
    equal(10, array.indexOf(3, 4));
    equal(10, array.indexOf(3, -5))
    equal(2, array.indexOf(3, {}), "nonsensical value for fromIndex");
    equal(2, array.indexOf(3, ""), "nonsensical value for fromIndex");
    equal(-1, array.indexOf(3, 41), "fromIndex value larger than the length of the array");
  });

  test('Array.prototype.forEach', function() {
    ok(typeof Array.prototype.forEach === 'function');

    var arr = [1,2,3];
    var result = [ ];

    arr.forEach(function(val, index, arr) {
      result.push(val, index, arr);
    });

    deepEqual(result, [1, 0, arr, 2, 1, arr, 3, 2, arr]);
  });

  test('Array.prototype.map', function() {

    ok(typeof Array.prototype.map === 'function');

    // borrowed from Prototype.js but modified to conform to standard

    deepEqual([2,4,6], [1,2,3].map(function(x) { return x * 2; }));

    var x = [1,2,3,4];
    delete x[1];
    delete x[3];
    deepEqual([1, undefined, 3, undefined], x.map(K));
    deepEqual(4, x.map(K).length);

    var traversed = [];
    x.map(function(val) {
      traversed.push(val);
    });
    deepEqual([1, 3], traversed);
    equal(2, traversed.length);
  });

  test('Array.prototype.every', function() {

    ok(typeof Array.prototype.every === 'function');

    // borrowed from Prototype.js but modified to conform to standard
    ok([].every(K));

    ok([true, true, true].every(K));
    ok(![true, false, false].every(K));
    ok(![false, false, false].every(K));

    ok([1,2,3,4,5].every(function(value) {
      return value > 0;
    }));
    ok(![1,2,3,4,5].every(function(value) {
      return value > 1;
    }));

    var x = [1,2,3], traversed = [];
    delete x[1];
    x.every(function(val) { traversed.push(val); return true; });

    deepEqual([1, 3], traversed);
    equal(2, traversed.length);
  });

  test('Array.prototype.some', function() {
    ok(typeof Array.prototype.some === 'function');

    // borrowed from Prototype.js but modified to conform to standard
    ok(!([].some(K)));

    ok([true, true, true].some(K));
    ok([true, false, false].some(K));
    ok(![false, false, false].some(K));

    ok([1,2,3,4,5].some(function(value) {
      return value > 2;
    }));
    ok(![1,2,3,4,5].some(function(value) {
      return value > 5;
    }));

    var x = [1,2,3], traversed = [];
    delete x[1];
    x.some(function(val) { traversed.push(val); });

    deepEqual([1, 3], traversed);
    equal(2, traversed.length);
  });

  test('Array.prototype.filter', function() {
    ok(typeof Array.prototype.filter === 'function');

    var arr = [1,2,3,4,5];
    deepEqual([3,4,5], arr.filter(function(val){ return val > 2 }));
    deepEqual([], arr.filter(function(val){ return val > 5 }));
    deepEqual([1,2], arr.filter(function(val){ return val <= 2 }));
  });

  test('Array.prototype.reduce', function() {
    ok(typeof Array.prototype.reduce === 'function');

    var arr = [1,2,3,4,5];
    equal(15,
      arr.reduce(function(memo, val) { return memo + val }), 0);

    deepEqual(['1!', '2!', '3!', '4!', '5!'],
      arr.reduce(function(memo, val) { memo.push(val + '!'); return memo }, [ ]));

    var arr = 'foobar'.split('');
    equal('f0o1o2b3a4r5',
      arr.reduce(function(memo, val, index) { return memo + val + index }, ''));
  });

  test('fabric.util.createClass', function() {
    var Klass = fabric.util.createClass();

    ok(typeof Klass === 'function');
    ok(typeof new Klass() === 'object');

    var Person = fabric.util.createClass({
      initialize: function(firstName, lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
      },
      toString: function() {
        return 'My name is ' + this.firstName + ' ' + this.lastName;
      }
    });

    ok(typeof Person === 'function');
    ok(typeof new Person() === 'object');

    var john = new Person('John', 'Meadows');
    ok(john instanceof Person);

    equal(john.firstName, 'John');
    equal(john.lastName, 'Meadows');
    equal(john + '', 'My name is John Meadows');


    var WebDeveloper = fabric.util.createClass(Person, {
      initialize: function(firstName, lastName, skills) {
        this.callSuper('initialize', firstName, lastName);
        this.skills = skills;
      },
      toString: function() {
        return this.callSuper('toString') + ' and my skills are ' + this.skills.join(', ');
      }
    });

    ok(typeof WebDeveloper === 'function');
    var dan = new WebDeveloper('Dan', 'Trink', ['HTML', 'CSS', 'Javascript']);
    ok(dan instanceof Person);
    ok(dan instanceof WebDeveloper);

    equal(dan.firstName, 'Dan');
    equal(dan.lastName, 'Trink');
    deepEqual(dan.skills, ['HTML', 'CSS', 'Javascript']);

    equal(dan + '', 'My name is Dan Trink and my skills are HTML, CSS, Javascript');
  });

  // test('fabric.util.setStyle', function() {
  // });

  // test('fabric.util.request', function() {
  // });

  // test('fabric.util.getPointer', function() {
  // });

  // test('fabric.util.addListener', function() {
  // });

  // test('fabric.util.removeListener', function() {
  // });

  test('fabric.util.array.invoke', function() {
    ok(typeof fabric.util.array.invoke === 'function');

    var obj1 = { toString: function(){ return 'obj1' } };
    var obj2 = { toString: function(){ return 'obj2' } };
    var obj3 = { toString: function(){ return 'obj3' } };

    deepEqual(['obj1', 'obj2', 'obj3'],
      fabric.util.array.invoke([ obj1, obj2, obj3 ], 'toString'));

    deepEqual(['f', 'b', 'b'],
      fabric.util.array.invoke(['foo', 'bar', 'baz'], 'charAt', 0));

    deepEqual(['o', 'a', 'a'],
      fabric.util.array.invoke(['foo', 'bar', 'baz'], 'charAt', 1));
  });

  test('fabric.util.array.min', function() {
    ok(typeof fabric.util.array.min === 'function');

    equal(1, fabric.util.array.min([1, 3, 2]));
    equal(-1, fabric.util.array.min([3, 1, 'f', 3, -1, 3]));
    equal(-3, fabric.util.array.min([-1, -2, -3]));
    equal('a', fabric.util.array.min(['a', 'c', 'b']));

    var obj1 = { valueOf: function(){ return 1 } };
    var obj2 = { valueOf: function(){ return 2 } };
    var obj3 = { valueOf: function(){ return 3 } };

    equal(obj1, fabric.util.array.min([ obj1, obj3, obj2 ]));
  });

  test('fabric.util.array.max', function() {
    ok(typeof fabric.util.array.max === 'function');

    equal(3, fabric.util.array.max([1, 3, 2]));
    equal(3, fabric.util.array.max([3, 1, 'f', 3, -1, 3]));
    equal(-1, fabric.util.array.max([-1, -2, -3]));
    equal('c', fabric.util.array.max(['a', 'c', 'b']));

    var obj1 = { valueOf: function(){ return 1 } };
    var obj2 = { valueOf: function(){ return 2 } };
    var obj3 = { valueOf: function(){ return 3 } };

    equal(obj3, fabric.util.array.max([ obj1, obj3, obj2 ]));
  });

  test('fabric.util.populateWithProperties', function() {
    ok(typeof fabric.util.populateWithProperties == 'function')

    var source = {
      foo: 'bar',
      baz: 123,
      qux: function() { }
    },
    destination = { };

    fabric.util.populateWithProperties(source, destination);
    ok(typeof destination.foo === 'undefined');
    ok(typeof destination.baz === 'undefined');
    ok(typeof destination.qux === 'undefined');

    fabric.util.populateWithProperties(source, destination, ['foo']);
    equal(destination.foo, 'bar');
    ok(typeof destination.baz === 'undefined');
    ok(typeof destination.qux === 'undefined');

    fabric.util.populateWithProperties(source, destination, ['foo', 'baz', 'ffffffffff']);
    equal(destination.foo, 'bar');
    equal(destination.baz, 123);
    ok(typeof destination.qux === 'undefined');
    ok(typeof destination.ffffffffff === 'undefined');
  });

})();