src/support.js

   1 (function() {
   2
   3         jQuery.support = {};
   4
   5         var root = document.documentElement,
   6                 script = document.createElement("script"),
   7                 div = document.createElement("div"),
   8                 id = "script" + now();
   9
  10         div.style.display = "none";
  11         div.innerHTML = "   <link/><table></table><a href='/a' style='color:red;float:left;opacity:.55;'>a</a><input type='checkbox'/>";
  12
  13         var all = div.getElementsByTagName("*"),
  14                 a = div.getElementsByTagName("a")[0];
  15
  16         // Can't get basic test support
  17         if ( !all || !all.length || !a ) {
  18                 return;
  19         }
  20
  21         jQuery.support = {
  22                 // IE strips leading whitespace when .innerHTML is used
  23                 leadingWhitespace: div.firstChild.nodeType === 3,
  24
  25                 // Make sure that tbody elements aren't automatically inserted
  26                 // IE will insert them into empty tables
  27                 tbody: !div.getElementsByTagName("tbody").length,
  28
  29                 // Make sure that link elements get serialized correctly by innerHTML
  30                 // This requires a wrapper element in IE
  31                 htmlSerialize: !!div.getElementsByTagName("link").length,
  32
  33                 // Get the style information from getAttribute
  34                 // (IE uses .cssText insted)
  35                 style: /red/.test( a.getAttribute("style") ),
  36
  37                 // Make sure that URLs aren't manipulated
  38                 // (IE normalizes it by default)
  39                 hrefNormalized: a.getAttribute("href") === "/a",
  40
  41                 // Make sure that element opacity exists
  42                 // (IE uses filter instead)
  43                 // Use a regex to work around a WebKit issue. See #5145
  44                 opacity: /^0.55$/.test( a.style.opacity ),
  45
  46                 // Verify style float existence
  47                 // (IE uses styleFloat instead of cssFloat)
  48                 cssFloat: !!a.style.cssFloat,
  49
  50                 // Make sure that if no value is specified for a checkbox
  51                 // that it defaults to "on".
  52                 // (WebKit defaults to "" instead)
  53                 checkOn: div.getElementsByTagName("input")[0].value === "on",
  54
  55                 // Make sure that a selected-by-default option has a working selected property.
  56                 // (WebKit defaults to false instead of true, IE too, if it's in an optgroup)
  57                 optSelected: document.createElement("select").appendChild( document.createElement("option") ).selected,
  58
  59                 // Will be defined later
  60                 checkClone: false,
  61                 scriptEval: false,
  62                 noCloneEvent: true,
  63                 boxModel: null
  64         };
  65
  66         script.type = "text/javascript";
  67         try {
  68                 script.appendChild( document.createTextNode( "window." + id + "=1;" ) );
  69         } catch(e) {}
  70
  71         root.insertBefore( script, root.firstChild );
  72
  73         // Make sure that the execution of code works by injecting a script
  74         // tag with appendChild/createTextNode
  75         // (IE doesn't support this, fails, and uses .text instead)
  76         if ( window[ id ] ) {
  77                 jQuery.support.scriptEval = true;
  78                 delete window[ id ];
  79         }
  80
  81         root.removeChild( script );
  82
  83         if ( div.attachEvent && div.fireEvent ) {
  84                 div.attachEvent("onclick", function click() {
  85                         // Cloning a node shouldn't copy over any
  86                         // bound event handlers (IE does this)
  87                         jQuery.support.noCloneEvent = false;
  88                         div.detachEvent("onclick", click);
  89                 });
  90                 div.cloneNode(true).fireEvent("onclick");
  91         }
  92
  93         div = document.createElement("div");
  94         div.innerHTML = "<input type='radio' name='radiotest' checked='checked'/>";
  95
  96         var fragment = document.createDocumentFragment();
  97         fragment.appendChild( div.firstChild );
  98
  99         // WebKit doesn't clone checked state correctly in fragments
 100         jQuery.support.checkClone = fragment.cloneNode(true).cloneNode(true).lastChild.checked;
 101
 102         // Figure out if the W3C box model works as expected
 103         // document.body must exist before we can do this
 104         jQuery(function() {
 105                 var div = document.createElement("div");
 106                 div.style.width = div.style.paddingLeft = "1px";
 107
 108                 document.body.appendChild( div );
 109                 jQuery.boxModel = jQuery.support.boxModel = div.offsetWidth === 2;
 110                 document.body.removeChild( div ).style.display = 'none';
 111                 div = null;
 112         });
 113
 114         // Technique from Juriy Zaytsev
 115         // http://thinkweb2.com/projects/prototype/detecting-event-support-without-browser-sniffing/
 116         var eventSupported = function( eventName ) {
 117                 var el = document.createElement("div");
 118                 eventName = "on" + eventName;
 119
 120                 var isSupported = (eventName in el);
 121                 if ( !isSupported ) {
 122                         el.setAttribute(eventName, "return;");
 123                         isSupported = typeof el[eventName] === "function";
 124                 }
 125                 el = null;
 126
 127                 return isSupported;
 128         };
 129
 130         jQuery.support.submitBubbles = eventSupported("submit");
 131         jQuery.support.changeBubbles = eventSupported("change");
 132
 133         // release memory in IE
 134         root = script = div = all = a = null;
 135 })();
 136
 137 jQuery.props = {
 138         "for": "htmlFor",
 139         "class": "className",
 140         readonly: "readOnly",
 141         maxlength: "maxLength",
 142         cellspacing: "cellSpacing",
 143         rowspan: "rowSpan",
 144         colspan: "colSpan",
 145         tabindex: "tabIndex",
 146         usemap: "useMap",
 147         frameborder: "frameBorder"
 148 };