Droppable: Changed drop event to loop over a copied array instead of …

…the droppables directly. Fixed #9116 - Droppable: Drop event can cause droppables to remain active if any droppable is created/destroyed in the event handler.

tests/unit/droppable/droppable.html

@@ -42,6 +42,7 @@ <h2 id="qunit-userAgent"></h2>
 
 <div id="draggable1" style="width: 25px; height: 25px;">Draggable</div>
 <div id="droppable1" style="width: 100px; height: 100px;">Droppable</div>
+<div id="droppable2" style="width: 100px; height: 100px;">Droppable</div>
 <div style='width:1000px;height:1000px;'>&nbsp;</div>
 
 </div>

tests/unit/droppable/droppable_events.js

@@ -5,6 +5,39 @@
 
 module("droppable: events");
 
+test( "droppable destruction/recreation on drop event", function() {
+	expect( 1 );
+
+	var config = {
+			activeClass: "active",
+			drop: function() {
+				var element = $( this ),
+					newDroppable = $( "<div>" )
+						.css({ width: 100, height: 100 })
+						.text( "Droppable" );
+				element.after( newDroppable );
+				element.remove();
+				newDroppable.droppable( config );
+			}
+		},
+
+		draggable = $( "#draggable1" ).draggable(),
+		droppable1 = $( "#droppable1" ).droppable( config ),
+		droppable2 = $( "#droppable2" ).droppable( config ),
+
+		droppableOffset = droppable1.offset(),
+		draggableOffset = draggable.offset(),
+		dx = droppableOffset.left - draggableOffset.left,
+		dy = droppableOffset.top - draggableOffset.top;
+
+	draggable.simulate( "drag", {
+		dx: dx,
+		dy: dy
+	});
+
+	ok( !droppable2.hasClass( "active" ), "subsequent droppable no longer active" );
+});
+
 // this is here to make JSHint pass "unused", and we don't want to
 // remove the parameter for when we finally implement
 $.noop();

ui/jquery.ui.droppable.js

@@ -278,7 +278,8 @@ $.ui.ddmanager = {
 	drop: function(draggable, event) {
 
 		var dropped = false;
-		$.each($.ui.ddmanager.droppables[draggable.options.scope] || [], function() {
+		// Create a copy of the droppables in case the list changes during the drop (#9116)
+		$.each(($.ui.ddmanager.droppables[draggable.options.scope] || []).slice(), function() {
 
 			if(!this.options) {
 				return;