Offset: allow offset setter to throw for disconnected elements

Fixes gh-2114

src/offset.js

@@ -39,7 +39,7 @@ jQuery.offset = {
 			elem.style.position = "relative";
 		}
 
-		curOffset = curElem.offset() || { top: 0, left: 0 };
+		curOffset = curElem.offset();
 		curCSSTop = jQuery.css( elem, "top" );
 		curCSSLeft = jQuery.css( elem, "left" );
 		calculatePosition = ( position === "absolute" || position === "fixed" ) &&

test/unit/core.js

@@ -36,10 +36,6 @@ test("jQuery()", function() {
 		expected++;
 		attrObj["width"] = 10;
 	}
-	if ( jQuery.fn.offset ) {
-		expected++;
-		attrObj["offset"] = { "top": 1, "left": 1 };
-	}
 	if ( jQuery.fn.css ) {
 		expected += 2;
 		attrObj["css"] = { "paddingLeft": 1, "paddingRight": 1 };
@@ -105,16 +101,12 @@ test("jQuery()", function() {
 	elem = jQuery("\n\n<em>world</em>")[0];
 	equal( elem.nodeName.toLowerCase(), "em", "leading newlines" );
 
-	elem = jQuery("<div/>", attrObj );
+	elem = jQuery( "<div/>", attrObj );
 
 	if ( jQuery.fn.width ) {
 		equal( elem[0].style.width, "10px", "jQuery() quick setter width");
 	}
 
-	if ( jQuery.fn.offset ) {
-		equal( elem[0].style.top, "1px", "jQuery() quick setter offset");
-	}
-
 	if ( jQuery.fn.css ) {
 		equal( elem[0].style.paddingLeft, "1px", "jQuery quick setter css");
 		equal( elem[0].style.paddingRight, "1px", "jQuery quick setter css");