Landing pull request 477. 1.7 jQuery.offset.supportsFixedPosition. Fixes #6809.

More Details:
 - https://github.com/jquery/jquery/pull/477
 - http://bugs.jquery.com/ticket/6809

diff --git a/src/offset.js b/src/offset.js
index 31f2503a41b0a073c343a66566d41eb867325bca..4cc87acff50b0f4f9a0d6f81a0fda5f233838c14 100644 (file)
--- a/src/offset.js
+++ b/src/offset.js
@@ -63,8 +63,6 @@ if ( "getBoundingClientRect" in document.documentElement ) {
                        return jQuery.offset.bodyOffset( elem );
                }
 
-               jQuery.offset.initialize();
-
                var computedStyle,
                        offsetParent = elem.offsetParent,
                        prevOffsetParent = elem,
@@ -120,46 +118,22 @@ if ( "getBoundingClientRect" in document.documentElement ) {
        };
 }
 
-jQuery.offset = {
-       initialize: function() {
-               var body = document.body, container = document.createElement("div"), innerDiv, checkDiv, table, td, bodyMarginTop = parseFloat( jQuery.css(body, "marginTop") ) || 0,
-                       html = "<div style='position:absolute;top:0;left:0;margin:0;border:5px solid #000;padding:0;width:1px;height:1px;'><div></div></div><table style='position:absolute;top:0;left:0;margin:0;border:5px solid #000;padding:0;width:1px;height:1px;' cellpadding='0' cellspacing='0'><tr><td></td></tr></table>";
-
-               jQuery.extend( container.style, { position: "absolute", top: 0, left: 0, margin: 0, border: 0, width: "1px", height: "1px", visibility: "hidden" } );
-
-               container.innerHTML = html;
-               body.insertBefore( container, body.firstChild );
-               innerDiv = container.firstChild;
-               checkDiv = innerDiv.firstChild;
-               td = innerDiv.nextSibling.firstChild.firstChild;
-
-               this.doesNotAddBorder = (checkDiv.offsetTop !== 5);
-               this.doesAddBorderForTableAndCells = (td.offsetTop === 5);
-
-               checkDiv.style.position = "fixed";
-               checkDiv.style.top = "20px";
-
-               // safari subtracts parent border width here which is 5px
-               this.supportsFixedPosition = (checkDiv.offsetTop === 20 || checkDiv.offsetTop === 15);
-               checkDiv.style.position = checkDiv.style.top = "";
+jQuery.offset = {};
 
-               innerDiv.style.overflow = "hidden";
-               innerDiv.style.position = "relative";
+jQuery.each(
+       ( "doesAddBorderForTableAndCells doesNotAddBorder " +
+               "doesNotIncludeMarginInBodyOffset subtractsBorderForOverflowNotVisible " +
+               "supportsFixedPosition" ).split(" "), function( i, prop ) {
 
-               this.subtractsBorderForOverflowNotVisible = (checkDiv.offsetTop === -5);
-
-               this.doesNotIncludeMarginInBodyOffset = (body.offsetTop !== bodyMarginTop);
+       jQuery.offset[ prop ] = jQuery.support[ prop ];
+});
 
-               body.removeChild( container );
-               jQuery.offset.initialize = jQuery.noop;
-       },
+jQuery.extend( jQuery.offset, {
 
        bodyOffset: function( body ) {
                var top = body.offsetTop,
                        left = body.offsetLeft;
 
-               jQuery.offset.initialize();
-
                if ( jQuery.offset.doesNotIncludeMarginInBodyOffset ) {
                        top  += parseFloat( jQuery.css(body, "marginTop") ) || 0;
                        left += parseFloat( jQuery.css(body, "marginLeft") ) || 0;
@@ -210,10 +184,11 @@ jQuery.offset = {
                        curElem.css( props );
                }
        }
-};
+});
 
 
 jQuery.fn.extend({
+
        position: function() {
                if ( !this[0] ) {
                        return null;

diff --git a/src/support.js b/src/support.js
index ad1bd9a57dbec9e7405b15d6582bfd4cd0a7067a..fb730dca70294d84d2eb39ee75dbb838b5786fda 100644 (file)
--- a/src/support.js
+++ b/src/support.js
@@ -20,7 +20,8 @@ jQuery.support = (function() {
                events,
                eventName,
                i,
-               isSupported;
+               isSupported,
+               offsetSupport;
 
        // Preliminary tests
        div.setAttribute("className", "t");
@@ -249,6 +250,49 @@ jQuery.support = (function() {
                }
        }
 
+       // Determine fixed-position support early
+       offsetSupport = (function( body, container ) {
+
+               var outer, inner, table, td, supports,
+                       bodyMarginTop = parseFloat( body.style.marginTop ) || 0,
+                       ptlm = "position:absolute;top:0;left:0;width:1px;height:1px;",
+                       style = "style='" + ptlm + "margin:0;border:5px solid #000;padding:0;'",
+                       html = "<div " + style + "><div></div></div>" +
+                                                       "<table " + style + " cellpadding='0' cellspacing='0'>" +
+                                                       "<tr><td></td></tr></table>";
+
+               container.style.cssText = ptlm + "border:0;visibility:hidden";
+
+               container.innerHTML = html;
+               body.insertBefore( container, body.firstChild );
+               outer = container.firstChild;
+               inner = outer.firstChild;
+               td = outer.nextSibling.firstChild.firstChild;
+
+               supports = {
+                       doesNotAddBorder: (inner.offsetTop !== 5),
+                       doesAddBorderForTableAndCells: (td.offsetTop === 5)
+               }
+
+               inner.style.position = "fixed";
+               inner.style.top = "20px";
+
+               // safari subtracts parent border width here which is 5px
+               supports.supportsFixedPosition = (inner.offsetTop === 20 || inner.offsetTop === 15);
+               inner.style.position = inner.style.top = "";
+
+               outer.style.overflow = "hidden";
+               outer.style.position = "relative";
+
+               supports.subtractsBorderForOverflowNotVisible = (inner.offsetTop === -5);
+               supports.doesNotIncludeMarginInBodyOffset = (body.offsetTop !== bodyMarginTop);
+
+               return supports;
+
+       })( testElement, div );
+
+       jQuery.extend( support, offsetSupport );
+
        // Null connected elements to avoid leaks in IE
        testElement = fragment = select = opt = body = marginDiv = div = input = null;
 

diff --git a/test/unit/offset.js b/test/unit/offset.js
index 79a0f36065f7a067e19fad044cd62e0f01aee58d..adb8a9ecabde387f88eaa7be8a7a83f0a8849ed5 100644 (file)
--- a/test/unit/offset.js
+++ b/test/unit/offset.js
@@ -267,8 +267,6 @@ testoffset("static", function( jQuery ) {
 testoffset("fixed", function( jQuery ) {
        expect(30);
 
-       jQuery.offset.initialize();
-
        var tests = [
                { id: "#fixed-1", top: 1001, left: 1001 },
                { id: "#fixed-2", top: 1021, left: 1021 }
@@ -403,8 +401,8 @@ testoffset("scroll", function( jQuery, win ) {
 testoffset("body", function( jQuery ) {
        expect(2);
 
-       equals( jQuery("body").offset().top, 1, "jQuery('#body').offset().top" );
-       equals( jQuery("body").offset().left, 1, "jQuery('#body').offset().left" );
+       equals( jQuery("body").offset().top, 0, "jQuery('#body').offset().top" );
+       equals( jQuery("body").offset().left, 0, "jQuery('#body').offset().left" );
 });
 
 test("Chaining offset(coords) returns jQuery object", function() {