Make sure that .find() with multiple direct child selectors is handled correctly...
[jquery.git] / src / support.js
1 (function( jQuery ) {
2
3 (function() {
4
5         jQuery.support = {};
6
7         var root = document.documentElement,
8                 script = document.createElement("script"),
9                 div = document.createElement("div"),
10                 id = "script" + jQuery.now();
11
12         div.style.display = "none";
13         div.innerHTML = "   <link/><table></table><a href='/a' style='color:red;float:left;opacity:.55;'>a</a><input type='checkbox'/>";
14
15         var all = div.getElementsByTagName("*"),
16                 a = div.getElementsByTagName("a")[0],
17                 select = document.createElement("select"),
18                 opt = select.appendChild( document.createElement("option") );
19
20         // Can't get basic test support
21         if ( !all || !all.length || !a ) {
22                 return;
23         }
24
25         jQuery.support = {
26                 // IE strips leading whitespace when .innerHTML is used
27                 leadingWhitespace: div.firstChild.nodeType === 3,
28
29                 // Make sure that tbody elements aren't automatically inserted
30                 // IE will insert them into empty tables
31                 tbody: !div.getElementsByTagName("tbody").length,
32
33                 // Make sure that link elements get serialized correctly by innerHTML
34                 // This requires a wrapper element in IE
35                 htmlSerialize: !!div.getElementsByTagName("link").length,
36
37                 // Get the style information from getAttribute
38                 // (IE uses .cssText insted)
39                 style: /red/.test( a.getAttribute("style") ),
40
41                 // Make sure that URLs aren't manipulated
42                 // (IE normalizes it by default)
43                 hrefNormalized: a.getAttribute("href") === "/a",
44
45                 // Make sure that element opacity exists
46                 // (IE uses filter instead)
47                 // Use a regex to work around a WebKit issue. See #5145
48                 opacity: /^0.55$/.test( a.style.opacity ),
49
50                 // Verify style float existence
51                 // (IE uses styleFloat instead of cssFloat)
52                 cssFloat: !!a.style.cssFloat,
53
54                 // Make sure that if no value is specified for a checkbox
55                 // that it defaults to "on".
56                 // (WebKit defaults to "" instead)
57                 checkOn: div.getElementsByTagName("input")[0].value === "on",
58
59                 // Make sure that a selected-by-default option has a working selected property.
60                 // (WebKit defaults to false instead of true, IE too, if it's in an optgroup)
61                 optSelected: opt.selected,
62
63                 // Will be defined later
64                 optDisabled: false,
65                 checkClone: false,
66                 scriptEval: false,
67                 noCloneEvent: true,
68                 boxModel: null,
69                 inlineBlockNeedsLayout: false,
70                 shrinkWrapBlocks: false,
71                 reliableHiddenOffsets: true
72         };
73
74         // Make sure that the options inside disabled selects aren't marked as disabled
75         // (WebKit marks them as diabled)
76         select.disabled = true;
77         jQuery.support.optDisabled = !opt.disabled;
78
79         script.type = "text/javascript";
80         try {
81                 script.appendChild( document.createTextNode( "window." + id + "=1;" ) );
82         } catch(e) {}
83
84         root.insertBefore( script, root.firstChild );
85
86         // Make sure that the execution of code works by injecting a script
87         // tag with appendChild/createTextNode
88         // (IE doesn't support this, fails, and uses .text instead)
89         if ( window[ id ] ) {
90                 jQuery.support.scriptEval = true;
91                 delete window[ id ];
92         }
93
94         root.removeChild( script );
95
96         if ( div.attachEvent && div.fireEvent ) {
97                 div.attachEvent("onclick", function click() {
98                         // Cloning a node shouldn't copy over any
99                         // bound event handlers (IE does this)
100                         jQuery.support.noCloneEvent = false;
101                         div.detachEvent("onclick", click);
102                 });
103                 div.cloneNode(true).fireEvent("onclick");
104         }
105
106         div = document.createElement("div");
107         div.innerHTML = "<input type='radio' name='radiotest' checked='checked'/>";
108
109         var fragment = document.createDocumentFragment();
110         fragment.appendChild( div.firstChild );
111
112         // WebKit doesn't clone checked state correctly in fragments
113         jQuery.support.checkClone = fragment.cloneNode(true).cloneNode(true).lastChild.checked;
114
115         // Figure out if the W3C box model works as expected
116         // document.body must exist before we can do this
117         jQuery(function() {
118                 var div = document.createElement("div");
119                 div.style.width = div.style.paddingLeft = "1px";
120
121                 document.body.appendChild( div );
122                 jQuery.boxModel = jQuery.support.boxModel = div.offsetWidth === 2;
123
124                 if ( "zoom" in div.style ) {
125                         // Check if natively block-level elements act like inline-block
126                         // elements when setting their display to 'inline' and giving
127                         // them layout
128                         // (IE < 8 does this)
129                         div.style.display = "inline";
130                         div.style.zoom = 1;
131                         jQuery.support.inlineBlockNeedsLayout = div.offsetWidth === 2;
132
133                         // Check if elements with layout shrink-wrap their children
134                         // (IE 6 does this)
135                         div.style.display = "";
136                         div.innerHTML = "<div style='width:4px;'></div>";
137                         jQuery.support.shrinkWrapBlocks = div.offsetWidth !== 2;
138                 }
139
140                 div.innerHTML = "<table><tr><td style='padding:0;display:none'></td><td>t</td></tr></table>";
141                 var tds = div.getElementsByTagName("td");
142
143                 // Check if table cells still have offsetWidth/Height when they are set
144                 // to display:none and there are still other visible table cells in a
145                 // table row; if so, offsetWidth/Height are not reliable for use when
146                 // determining if an element has been hidden directly using
147                 // display:none (it is still safe to use offsets if a parent element is
148                 // hidden; don safety goggles and see bug #4512 for more information).
149                 // (only IE 8 fails this test)
150                 jQuery.support.reliableHiddenOffsets = tds[0].offsetHeight === 0;
151
152                 tds[0].style.display = "";
153                 tds[1].style.display = "none";
154
155                 // Check if empty table cells still have offsetWidth/Height
156                 // (IE < 8 fail this test)
157                 jQuery.support.reliableHiddenOffsets = jQuery.support.reliableHiddenOffsets && tds[0].offsetHeight === 0;
158                 div.innerHTML = "";
159
160                 document.body.removeChild( div ).style.display = "none";
161                 div = tds = null;
162         });
163
164         // Technique from Juriy Zaytsev
165         // http://thinkweb2.com/projects/prototype/detecting-event-support-without-browser-sniffing/
166         var eventSupported = function( eventName ) {
167                 var el = document.createElement("div");
168                 eventName = "on" + eventName;
169
170                 var isSupported = (eventName in el);
171                 if ( !isSupported ) {
172                         el.setAttribute(eventName, "return;");
173                         isSupported = typeof el[eventName] === "function";
174                 }
175                 el = null;
176
177                 return isSupported;
178         };
179
180         jQuery.support.submitBubbles = eventSupported("submit");
181         jQuery.support.changeBubbles = eventSupported("change");
182
183         // release memory in IE
184         root = script = div = all = a = null;
185 })();
186
187 jQuery.props = {
188         "for": "htmlFor",
189         "class": "className",
190         readonly: "readOnly",
191         maxlength: "maxLength",
192         cellspacing: "cellSpacing",
193         rowspan: "rowSpan",
194         colspan: "colSpan",
195         tabindex: "tabIndex",
196         usemap: "useMap",
197         frameborder: "frameBorder"
198 };
199
200 })( jQuery );