Fix #12127. IE9/10 checks fall off the box on clone. Close gh-873.

AUTHORS.txt

@@ -129,3 +129,4 @@ David Benjamin <davidben@mit.edu>
 Uri Gilad <antishok@gmail.com>
 Chris Faulkner <thefaulkner@gmail.com>
 Elijah Manor <elijah.manor@gmail.com>
+Daniel Chatfield <chatfielddaniel@googlemail.com>

src/manipulation.js

@@ -455,9 +455,7 @@ function cloneFixAttributes( src, dest ) {
 		// IE6-8 fails to persist the checked state of a cloned checkbox
 		// or radio button. Worse, IE6-7 fail to give the cloned element
 		// a checked appearance if the defaultChecked value isn't also set
-		if ( src.checked ) {
-			dest.defaultChecked = dest.checked = src.checked;
-		}
+		dest.defaultChecked = dest.checked = src.checked;
 
 		// IE6-7 get confused and end up setting the value of a cloned
 		// checkbox/radio button to an empty string instead of "on"

src/support.js

@@ -15,7 +15,7 @@ jQuery.support = (function() {
 
 	// Preliminary tests
 	div.setAttribute( "className", "t" );
-	div.innerHTML = "  <link/><table></table><a href='/a'>a</a><input type='checkbox'/>";
+	div.innerHTML = "  <link/><table></table><a href='/a'>a</a><input type='checkbox' checked='checked'/>";
 
 	all = div.getElementsByTagName("*");
 	a = div.getElementsByTagName("a")[ 0 ];
@@ -96,8 +96,8 @@ jQuery.support = (function() {
 	};
 
 	// Make sure checked status is properly cloned
-	input.checked = true;
-	support.noCloneChecked = input.cloneNode( true ).checked;
+	input.checked = false;
+	support.noCloneChecked = !input.cloneNode( true ).checked;
 
 	// Make sure that the options inside disabled selects aren't marked as disabled
 	// (WebKit marks them as disabled)

test/unit/manipulation.js

@@ -1895,3 +1895,14 @@ test("html() - script exceptions bubble (#11743)", function() {
 		ok( false, "error ignored" );
 	}, "exception bubbled from remote script" );
 });
+
+test("checked state is cloned with clone()", function(){
+	expect(2);
+
+	var elem = jQuery.parseHTML('<input type="checkbox" checked="checked"/>')[0];
+	elem.checked = false;
+	equal( jQuery(elem).clone().attr('id','clone')[0].checked, false, 'Checked false state correctly cloned' );
+	elem = jQuery.parseHTML('<input type="checkbox"/>')[0];
+	elem.checked = true;
+	equal( jQuery(elem).clone().attr('id','clone')[0].checked, true, 'Checked true state correctly cloned' );
+});