ie8.js

  /*! (C) WebReflection Mit Style License */
  if (document.createEvent) return;
  var
    DUNNOABOUTDOMLOADED = true,
    READYEVENTDISPATCHED = false,
    ONREADYSTATECHANGE = 'onreadystatechange',
    DOMCONTENTLOADED = 'DOMContentLoaded',
    SECRET = '__IE8__' + Math.random(),
    // Object = window.Object,
    defineProperty = Object.defineProperty ||
    // just in case ...
    function (object, property, descriptor) {
      object[property] = descriptor.value;
    },
    defineProperties = Object.defineProperties ||
    // IE8 implemented defineProperty but not the plural...
    function (object, descriptors) {
      for(var key in descriptors) {
        if (hasOwnProperty.call(descriptors, key)) {
          try {
            defineProperty(object, key, descriptors[key]);
          } catch(o_O) {
            if (window.console) {
              console.log(key + ' failed on object:', object, o_O.message);
            }
          }
        }
      }
    },
    getOwnPropertyDescriptor = Object.getOwnPropertyDescriptor,
    hasOwnProperty = Object.prototype.hasOwnProperty,
    // here IE7 will break like a charm
    ElementPrototype = window.Element.prototype,
    TextPrototype = window.Text.prototype,
    // none of above native constructors exist/are exposed
    possiblyNativeEvent = /^[a-z]+$/,
    // ^ actually could probably be just /^[a-z]+$/
    readyStateOK = /loaded|complete/,
    types = {},
    div = document.createElement('div'),
    html = document.documentElement,
    removeAttribute = html.removeAttribute,
    setAttribute = html.setAttribute,
    valueDesc = function (value) {
      return {
        enumerable: true,
        writable: true,
        configurable: true,
        value: value
      };
    }
  ;

  function commonEventLoop(currentTarget, e, $handlers, synthetic) {
    for(var
      handler,
      continuePropagation,
      handlers = $handlers.slice(),
      evt = enrich(e, currentTarget),
      i = 0, length = handlers.length; i < length; i++
    ) {
      handler = handlers[i];
      if (typeof handler === 'object') {
        if (typeof handler.handleEvent === 'function') {
          handler.handleEvent(evt);
        }
      } else {
        handler.call(currentTarget, evt);
      }
      if (evt.stoppedImmediatePropagation) break;
    }
    continuePropagation = !evt.stoppedPropagation;
    /*
    if (continuePropagation && !synthetic && !live(currentTarget)) {
      evt.cancelBubble = true;
    }
    */
    return (
      synthetic &&
      continuePropagation &&
      currentTarget.parentNode
    ) ?
      currentTarget.parentNode.dispatchEvent(evt) :
      !evt.defaultPrevented
    ;
  }

  function commonDescriptor(get, set) {
    return {
      // if you try with enumerable: true
      // IE8 will miserably fail
      configurable: true,
      get: get,
      set: set
    };
  }

  function commonTextContent(protoDest, protoSource, property) {
    var descriptor = getOwnPropertyDescriptor(
      protoSource || protoDest, property
    );
    defineProperty(
      protoDest,
      'textContent',
      commonDescriptor(
        function () {
          return descriptor.get.call(this);
        },
        function (textContent) {
          descriptor.set.call(this, textContent);
        }
      )
    );
  }

  function enrich(e, currentTarget) {
    e.currentTarget = currentTarget;
    e.eventPhase = (
      // AT_TARGET : BUBBLING_PHASE
      e.target === e.currentTarget ? 2 : 3
    );
    return e;
  }

  function find(array, value) {
    var i = array.length;
    while(i-- && array[i] !== value);
    return i;
  }

  function getTextContent() {
    if (this.tagName === 'BR') return '\n';
    var
      textNode = this.firstChild,
      arrayContent = []
    ;
    while(textNode) {
      if (textNode.nodeType !== 8 && textNode.nodeType !== 7) {
        arrayContent.push(textNode.textContent);
      }
      textNode = textNode.nextSibling;
    }
    return arrayContent.join('');
  }

  function live(self) {
    return self.nodeType !== 9 && html.contains(self);
  }

  function onkeyup(e) {
    var evt = document.createEvent('Event');
    evt.initEvent('input', true, true);
    (e.srcElement || e.fromElement || document).dispatchEvent(evt);
  }

  function onReadyState(e) {
    if (!READYEVENTDISPATCHED && readyStateOK.test(
      document.readyState
    )) {
      READYEVENTDISPATCHED = !READYEVENTDISPATCHED;
      document.detachEvent(ONREADYSTATECHANGE, onReadyState);
      e = document.createEvent('Event');
      e.initEvent(DOMCONTENTLOADED, true, true);
      document.dispatchEvent(e);
    }
  }
  
  function getter(attr) {
    return function() {
      return html[attr] || (document.body && document.body[attr]) || 0;
    };
  }

  function setTextContent(textContent) {
    var node;
    while ((node = this.lastChild)) {
      this.removeChild(node);
    }
    /*jshint eqnull:true */
    if (textContent != null) {
      this.appendChild(document.createTextNode(textContent));
    }
  }

  function verify(self, e) {
    if (!e) {
      e = window.event;
    }
    if (!e.target) {
      e.target = e.srcElement || e.fromElement || document;
    }
    if (!e.timeStamp) {
      e.timeStamp = (new Date()).getTime();
    }
    return e;
  }

  // normalized textContent for:
  //  comment, script, style, text, title
  commonTextContent(
    window.HTMLCommentElement.prototype,
    ElementPrototype,
    'nodeValue'
  );

  commonTextContent(
    window.HTMLScriptElement.prototype,
    null,
    'text'
  );

  commonTextContent(
    TextPrototype,
    null,
    'nodeValue'
  );

  commonTextContent(
    window.HTMLTitleElement.prototype,
    null,
    'text'
  );

  defineProperty(
    window.HTMLStyleElement.prototype,
    'textContent',
    (function(descriptor){
      return commonDescriptor(
        function () {
          return descriptor.get.call(this.styleSheet);
        },
        function (textContent) {
          descriptor.set.call(this.styleSheet, textContent);
        }
      );
    }(getOwnPropertyDescriptor(window.CSSStyleSheet.prototype, 'cssText')))
  );

  var opacityre = /\b\s*alpha\s*\(\s*opacity\s*=\s*(\d+)\s*\)/;
  defineProperty(
    window.CSSStyleDeclaration.prototype,
    'opacity', {
      get: function() {
        var m = this.filter.match(opacityre);
        return m ? (m[1] / 100).toString() : '';
      },
      set: function(value) {
        this.zoom = 1;
        var found = false;
        if (value < 1) {
          value = ' alpha(opacity=' + Math.round(value * 100) + ')';
        }
        else {
          value = '';
        }
        this.filter = this.filter.replace(opacityre,
                        function() { found = true; return value; });
        if (!found && value) {
          this.filter += value;
        }
      }
    }
  );

  defineProperties(
    ElementPrototype,
    {
      // bonus
      textContent: {
        get: getTextContent,
        set: setTextContent
      },
      // http://www.w3.org/TR/ElementTraversal/#interface-elementTraversal
      firstElementChild: {
        get: function () {
          for(var
            childNodes = this.childNodes || [],
            i = 0, length = childNodes.length;
            i < length; i++
          ) {
            if (childNodes[i].nodeType == 1) return childNodes[i];
          }
        }
      },
      lastElementChild: {
        get: function () {
          for(var
            childNodes = this.childNodes || [],
            i = childNodes.length;
            i--;
          ) {
            if (childNodes[i].nodeType == 1) return childNodes[i];
          }
        }
      },
      oninput: {
        get: function () {
          return this._oninput || null;
        },
        set: function (oninput) {
          if (this._oninput) {
            this.removeEventListener('input', this._oninput);
            this._oninput = oninput;
            if (oninput) {
              this.addEventListener('input', oninput);
            }
          }
        }
      },
      previousElementSibling: {
        get: function () {
          var previousElementSibling = this.previousSibling;
          while (previousElementSibling && previousElementSibling.nodeType != 1) {
            previousElementSibling = previousElementSibling.previousSibling;
          }
          return previousElementSibling;
        }
      },
      nextElementSibling: {
        get: function () {
          var nextElementSibling = this.nextSibling;
          while (nextElementSibling && nextElementSibling.nodeType != 1) {
            nextElementSibling = nextElementSibling.nextSibling;
          }
          return nextElementSibling;
        }
      },
      childElementCount: {
        get: function () {
          for(var
            count = 0,
            childNodes = this.childNodes || [],
            i = childNodes.length; i--; count += childNodes[i].nodeType == 1
          );
          return count;
        }
      },
      /*
      // children would be an override
      // IE8 already supports them but with comments too
      // not just nodeType 1
      children: {
        get: function () {
          for(var
            children = [],
            childNodes = this.childNodes || [],
            i = 0, length = childNodes.length;
            i < length; i++
          ) {
            if (childNodes[i].nodeType == 1) {
              children.push(childNodes[i]);
            }
          }
          return children;
        }
      },
      */
      // DOM Level 2 EventTarget methods and events
      addEventListener: valueDesc(function (type, handler, capture) {
        if (typeof handler !== 'function' && typeof handler !== 'object') return;
        var
          self = this,
          ontype = 'on' + type,
          temple =  self[SECRET] ||
                      defineProperty(
                        self, SECRET, {value: {}}
                      )[SECRET],
          currentType = temple[ontype] || (temple[ontype] = {}),
          handlers  = currentType.h || (currentType.h = []),
          e, attr
        ;
        if (!hasOwnProperty.call(currentType, 'w')) {
          currentType.w = function (e) {
            // e[SECRET] is a silent notification needed to avoid
            // fired events during live test
            return e[SECRET] || commonEventLoop(self, verify(self, e), handlers, false);
          };
          // if not detected yet
          if (!hasOwnProperty.call(types, ontype)) {
            // and potentially a native event
            if(possiblyNativeEvent.test(type)) {
              // do this heavy thing
              try {
                // TODO:  should I consider tagName too so that
                //        INPUT[ontype] could be different ?
                e = document.createEventObject();
                // do not clone ever a node
                // specially a document one ...
                // use the secret to ignore them all
                e[SECRET] = true;
                // document a part if a node has never been
                // added to any other node, fireEvent might
                // behave very weirdly (read: trigger unspecified errors)
                if (self.nodeType != 9) {
                  /*jshint eqnull:true */
                  if (self.parentNode == null) {
                    div.appendChild(self);
                  }
                  if ((attr = self.getAttribute(ontype))) {
                    removeAttribute.call(self, ontype);
                  }
                }
                self.fireEvent(ontype, e);
                types[ontype] = true;
              } catch(meh) {
                types[ontype] = false;
                while (div.hasChildNodes()) {
                  div.removeChild(div.firstChild);
                }
              }
              if (attr != null) {
                setAttribute.call(self, ontype, attr);
              }
            } else {
              // no need to bother since
              // 'x-event' ain't native for sure
              types[ontype] = false;
            }
          }
          if ((currentType.n = types[ontype])) {
            self.attachEvent(ontype, currentType.w);
          }
        }
        if (find(handlers, handler) < 0) {
          handlers[capture ? 'unshift' : 'push'](handler);
        }
        if (type === 'input') {
          self.attachEvent('onkeyup', onkeyup);
        }
      }),
      dispatchEvent: valueDesc(function (e) {
        var
          self = this,
          ontype = 'on' + e.type,
          temple =  self[SECRET],
          currentType = temple && temple[ontype],
          valid = !!currentType,
          parentNode
        ;
        if (!e.target) e.target = self;
        return (valid ? (
          currentType.n /* && live(self) */ ?
            self.fireEvent(ontype, e) :
            commonEventLoop(
              self,
              e,
              currentType.h,
              true
            )
        ) : (
          (parentNode = self.parentNode) /* && live(self) */ ?
            parentNode.dispatchEvent(e) :
            true
        )), !e.defaultPrevented;
      }),
      removeEventListener: valueDesc(function (type, handler, capture) {
        if (typeof handler !== 'function' && typeof handler !== 'object') return;
        var
          self = this,
          ontype = 'on' + type,
          temple =  self[SECRET],
          currentType = temple && temple[ontype],
          handlers = currentType && currentType.h,
          i = handlers ? find(handlers, handler) : -1
        ;
        if (-1 < i) handlers.splice(i, 1);
      })
    }
  );

  /* this is not needed in IE8
  defineProperties(window.HTMLSelectElement.prototype, {
    value: {
      get: function () {
        return this.options[this.selectedIndex].value;
      }
    }
  });
  //*/

  // EventTarget methods for Text nodes too
  defineProperties(TextPrototype, {
    addEventListener: valueDesc(ElementPrototype.addEventListener),
    dispatchEvent: valueDesc(ElementPrototype.dispatchEvent),
    removeEventListener: valueDesc(ElementPrototype.removeEventListener)
  });

  defineProperties(
    window.XMLHttpRequest.prototype,
    {
      addEventListener: valueDesc(function (type, handler, capture) {
        var
          self = this,
          ontype = 'on' + type,
          temple =  self[SECRET] ||
                      defineProperty(
                        self, SECRET, {value: {}}
                      )[SECRET],
          currentType = temple[ontype] || (temple[ontype] = {}),
          handlers  = currentType.h || (currentType.h = [])
        ;
        if (find(handlers, handler) < 0) {
          if (!self[ontype]) {
            self[ontype] = function () {
              var e = document.createEvent('Event');
              e.initEvent(type, true, true);
              self.dispatchEvent(e);
            };
          }
          handlers[capture ? 'unshift' : 'push'](handler);
        }
      }),
      dispatchEvent: valueDesc(function (e) {
        var
          self = this,
          ontype = 'on' + e.type,
          temple =  self[SECRET],
          currentType = temple && temple[ontype],
          valid = !!currentType
        ;
        return valid && (
          currentType.n /* && live(self) */ ?
            self.fireEvent(ontype, e) :
            commonEventLoop(
              self,
              e,
              currentType.h,
              true
            )
        );
      }),
      removeEventListener: valueDesc(ElementPrototype.removeEventListener)
    }
  );

  var buttonGetter = getOwnPropertyDescriptor(Event.prototype, 'button').get;
  defineProperties(
    window.Event.prototype,
    {
      bubbles: valueDesc(true),
      cancelable: valueDesc(true),
      preventDefault: valueDesc(function () {
        if (this.cancelable) {
          this.returnValue = false;
        }
      }),
      stopPropagation: valueDesc(function () {
        this.stoppedPropagation = true;
        this.cancelBubble = true;
      }),
      stopImmediatePropagation: valueDesc(function () {
        this.stoppedImmediatePropagation = true;
        this.stopPropagation();
      }),
      initEvent: valueDesc(function(type, bubbles, cancelable){
        this.type = type;
        this.bubbles = !!bubbles;
        this.cancelable = !!cancelable;
        if (!this.bubbles) {
          this.stopPropagation();
        }
      }),
      pageX: {get: function(){ return this._pageX || (this._pageX = this.clientX + window.scrollX - (html.clientLeft || 0)); }},
      pageY: {get: function(){ return this._pageY || (this._pageY = this.clientY + window.scrollY - (html.clientTop || 0)); }},
      which: {get: function(){ return this.keyCode ? this.keyCode : (isNaN(this.button) ? undefined : this.button + 1); }},
      charCode: {get: function(){ return (this.keyCode && this.type == 'keypress') ? this.keyCode : 0; }},
      buttons: {get: function(){ return buttonGetter.call(this); }},
      button: {get: function() {
        var buttons = this.buttons;
        return (buttons & 1 ? 0 : (buttons & 2 ? 2 : (buttons & 4 ? 1 : undefined)));
      }},
      defaultPrevented: {get: function() {
        // if preventDefault() was never called, or returnValue not given a value
        // then returnValue is undefined
        var returnValue = this.returnValue, undef;
        return !(returnValue === undef || returnValue);
      }},
      relatedTarget: {get: function() {
        var type = this.type;
        if (type === 'mouseover') {
          return this.fromElement;
        } else if (type === 'mouseout') {
          return this.toElement;
        } else {
          return null;
        }
      }}
    }
  );

  defineProperties(
    window.HTMLDocument.prototype,
    {
      defaultView: {
        get: function () {
          return this.parentWindow;
        }
      },
      textContent: {
        get: function () {
          return this.nodeType === 11 ? getTextContent.call(this) : null;
        },
        set: function (textContent) {
          if (this.nodeType === 11) {
            setTextContent.call(this, textContent);
          }
        }
      },
      addEventListener: valueDesc(function(type, handler, capture) {
        var self = this;
        ElementPrototype.addEventListener.call(self, type, handler, capture);
        // NOTE:  it won't fire if already loaded, this is NOT a $.ready() shim!
        //        this behaves just like standard browsers
        if (
          DUNNOABOUTDOMLOADED &&
          type === DOMCONTENTLOADED &&
          !readyStateOK.test(
            self.readyState
          )
        ) {
          DUNNOABOUTDOMLOADED = false;
          self.attachEvent(ONREADYSTATECHANGE, onReadyState);
          /* global top */
          if (window == top) {
            (function gonna(e){try{
              self.documentElement.doScroll('left');
              onReadyState();
              }catch(o_O){
              setTimeout(gonna, 50);
            }}());
          }
        }
      }),
      dispatchEvent: valueDesc(ElementPrototype.dispatchEvent),
      removeEventListener: valueDesc(ElementPrototype.removeEventListener),
      createEvent: valueDesc(function(Class){
        var e;
        if (Class !== 'Event') throw new Error('unsupported ' + Class);
        e = document.createEventObject();
        e.timeStamp = (new Date()).getTime();
        return e;
      })
    }
  );

  defineProperties(
    window.Window.prototype,
    {
      getComputedStyle: valueDesc(function(){

        var // partially grabbed from jQuery and Dean's hack
          notpixel = /^(?:[+-]?(?:\d*\.|)\d+(?:[eE][+-]?\d+|))(?!px)[a-z%]+$/,
          position = /^(top|right|bottom|left)$/,
          re = /\-([a-z])/g,
          place = function (match, $1) {
            return $1.toUpperCase();
          }
        ;

        function ComputedStyle(_) {
          this._ = _;
        }

        ComputedStyle.prototype.getPropertyValue = function (name) {
          var
            el = this._,
            style = el.style,
            currentStyle = el.currentStyle,
            runtimeStyle = el.runtimeStyle,
            result,
            left,
            rtLeft
          ;
          if (name == 'opacity') {
            return style.opacity || '1';
          }
          name = (name === 'float' ? 'style-float' : name).replace(re, place);
          result = currentStyle ? currentStyle[name] : style[name];
          if (notpixel.test(result) && !position.test(name)) {
            left = style.left;
            rtLeft = runtimeStyle && runtimeStyle.left;
            if (rtLeft) {
              runtimeStyle.left = currentStyle.left;
            }
            style.left = name === 'fontSize' ? '1em' : result;
            result = style.pixelLeft + 'px';
            style.left = left;
            if (rtLeft) {
              runtimeStyle.left = rtLeft;
            }
          }
          /*jshint eqnull:true */
          return result == null ?
            result : ((result + '') || 'auto');
        };

        // unsupported
        function PseudoComputedStyle() {}
        PseudoComputedStyle.prototype.getPropertyValue = function () {
          return null;
        };

        return function (el, pseudo) {
          return pseudo ?
            new PseudoComputedStyle(el) :
            new ComputedStyle(el);
        };

      }()),

      addEventListener: valueDesc(function (type, handler, capture) {
        var
          self = window,
          ontype = 'on' + type,
          handlers
        ;
        if (!self[ontype]) {
          self[ontype] = function(e) {
            return commonEventLoop(self, verify(self, e), handlers, false) && undefined;
          };
        }
        handlers = self[ontype][SECRET] || (
          self[ontype][SECRET] = []
        );
        if (find(handlers, handler) < 0) {
          handlers[capture ? 'unshift' : 'push'](handler);
        }
      }),
      dispatchEvent: valueDesc(function (e) {
        var method = window['on' + e.type];
        return method ? method.call(window, e) !== false && !e.defaultPrevented : true;
      }),
      removeEventListener: valueDesc(function (type, handler, capture) {
        var
          ontype = 'on' + type,
          handlers = (window[ontype] || Object)[SECRET],
          i = handlers ? find(handlers, handler) : -1
         ;
        if (-1 < i) handlers.splice(i, 1);
      }),
      pageXOffset: {get: getter('scrollLeft')},
      pageYOffset: {get: getter('scrollTop')},
      scrollX: {get: getter('scrollLeft')},
      scrollY: {get: getter('scrollTop')},
      innerWidth: {get: getter('clientWidth')},
      innerHeight: {get: getter('clientHeight')}
    }
  );

  window.HTMLElement = window.Element;

  (function (styleSheets, HTML5Element, i) {
    for (i = 0; i < HTML5Element.length; i++) document.createElement(HTML5Element[i]);
    if (!styleSheets.length) document.createStyleSheet('');
    styleSheets[0].addRule(HTML5Element.join(','), 'display:block;');
  }(document.styleSheets, ['header', 'nav', 'section', 'article', 'aside', 'footer']));

  (function () {
    if (document.createRange) return;
    document.createRange = function createRange() {
      return new Range();
    };
  
    function getContents(start, end) {
      var nodes = [start];
      while (start !== end) {
        nodes.push(start = start.nextSibling);
      }
      return nodes;
    }
  
    function Range() {}
    var proto = Range.prototype;
    proto.cloneContents = function cloneContents() {
      for (var
        fragment = this._start.ownerDocument.createDocumentFragment(),
        nodes = getContents(this._start, this._end),
        i = 0,
        length = nodes.length;
        i < length; i++
      ) {
        fragment.appendChild(nodes[i].cloneNode(true));
      }
      return fragment;
    };
    proto.cloneRange = function cloneRange() {
      var range = new Range();
      range._start = this._start;
      range._end = this._end;
      return range;
    };
    proto.deleteContents = function deleteContents() {
      for (var
        parentNode = this._start.parentNode,
        nodes = getContents(this._start, this._end),
        i = 0,
        length = nodes.length;
        i < length; i++
      ) {
        parentNode.removeChild(nodes[i]);
      }
    };
    proto.extractContents = function extractContents() {
      for (var
        fragment = this._start.ownerDocument.createDocumentFragment(),
        nodes = getContents(this._start, this._end),
        i = 0,
        length = nodes.length;
        i < length; i++
      ) {
        fragment.appendChild(nodes[i]);
      }
      return fragment;
    };
    proto.setEndAfter = function setEndAfter(node) {
      this._end = node;
    };
    proto.setEndBefore = function setEndBefore(node) {
      this._end = node.previousSibling;
    };
    proto.setStartAfter = function setStartAfter(node) {
      this._start = node.nextSibling;
    };
    proto.setStartBefore = function setStartBefore(node) {
      this._start = node;
    };
  }());