Adds fn.promise as a mean to observe the completion of animations on …

…a set of elements. Only queued animations are handled for now, non-queued animations support coming soon. Effects unit tests updated to test the feature (needs more testing though).

src/queue.js

@@ -28,7 +28,8 @@ jQuery.extend({
 		type = type || "fx";
 
 		var queue = jQuery.queue( elem, type ),
-			fn = queue.shift();
+			fn = queue.shift(),
+			defer;
 
 		// If the fx queue is dequeued, always remove the progress sentinel
 		if ( fn === "inprogress" ) {
@@ -49,6 +50,17 @@ jQuery.extend({
 
 		if ( !queue.length ) {
 			jQuery.removeData( elem, type + "queue", true );
+			// Look if we have observers and resolve if needed
+			if (( defer = jQuery.data( elem, type + "defer", undefined, true ) )) {
+				// Give room for hard-coded callbacks to fire first
+				// and eventually add another animation on the element
+				setTimeout( function() {
+					if ( !jQuery.data( elem, type + "queue", undefined, true ) ) {
+						jQuery.removeData( elem, type + "defer", true );
+						defer.resolve();
+					}
+				}, 0 );
+			}
 		}
 	}
 });
@@ -93,6 +105,37 @@ jQuery.fn.extend({
 
 	clearQueue: function( type ) {
 		return this.queue( type || "fx", [] );
+	},
+
+	// Get a promise resolved when queues of a certain type
+	// are emptied (fx is the type by default)
+	promise: function( type, object ) {
+		if ( typeof type !== "string" ) {
+			object = type;
+			type = undefined;
+		}
+		type = type || "fx";
+		var defer = jQuery.Deferred(),
+			elements = this,
+			i = elements.length,
+			count = 1,
+			deferDataKey = type + "defer",
+			queueDataKey = type + "queue";
+		function resolve() {
+			if ( !( --count ) ) {
+				defer.resolveWith( elements, [ elements ] );
+			}
+		}
+		while( i-- ) {
+			if (( tmp = jQuery.data( elements[ i ], deferDataKey, undefined, true ) ||
+					jQuery.data( elements[ i ], queueDataKey, undefined, true ) &&
+					jQuery.data( elements[ i ], deferDataKey, jQuery._Deferred(), true ) )) {
+				count++;
+				tmp.done( resolve );
+			}
+		}
+		resolve();
+		return defer.promise();
 	}
 });
 

test/unit/effects.js

@@ -717,59 +717,64 @@ jQuery.each( {
 
 			var anim = { width: t_w, height: t_h, opacity: t_o };
 
-			elem.animate(anim, 50, function(){
+			elem.animate(anim, 50);
+
+			jQuery.when( elem ).done(function( elem ){
+
+				elem = elem[ 0 ];
+
 				if ( t_w == "show" )
-					equals( this.style.display, "block", "Showing, display should block: " + this.style.display);
+					equals( elem.style.display, "block", "Showing, display should block: " + elem.style.display);
 
 				if ( t_w == "hide"||t_w == "show" )
-					ok(f_w === "" ? this.style.width === f_w : this.style.width.indexOf(f_w) === 0, "Width must be reset to " + f_w + ": " + this.style.width);
+					ok(f_w === "" ? elem.style.width === f_w : elem.style.width.indexOf(f_w) === 0, "Width must be reset to " + f_w + ": " + elem.style.width);
 
 				if ( t_h == "hide"||t_h == "show" )
-					ok(f_h === "" ? this.style.height === f_h : this.style.height.indexOf(f_h) === 0, "Height must be reset to " + f_h + ": " + this.style.height);
+					ok(f_h === "" ? elem.style.height === f_h : elem.style.height.indexOf(f_h) === 0, "Height must be reset to " + f_h + ": " + elem.style.height);
 
-				var cur_o = jQuery.style(this, "opacity");
+				var cur_o = jQuery.style(elem, "opacity");
 
 				if ( t_o == "hide" || t_o == "show" )
 					equals(cur_o, f_o, "Opacity must be reset to " + f_o + ": " + cur_o);
 
 				if ( t_w == "hide" )
-					equals(this.style.display, "none", "Hiding, display should be none: " + this.style.display);
+					equals(elem.style.display, "none", "Hiding, display should be none: " + elem.style.display);
 
 				if ( t_o.constructor == Number ) {
 					equals(cur_o, t_o, "Final opacity should be " + t_o + ": " + cur_o);
 
-					ok(jQuery.css(this, "opacity") != "" || cur_o == t_o, "Opacity should be explicitly set to " + t_o + ", is instead: " + cur_o);
+					ok(jQuery.css(elem, "opacity") != "" || cur_o == t_o, "Opacity should be explicitly set to " + t_o + ", is instead: " + cur_o);
 				}
 
 				if ( t_w.constructor == Number ) {
-					equals(this.style.width, t_w + "px", "Final width should be " + t_w + ": " + this.style.width);
+					equals(elem.style.width, t_w + "px", "Final width should be " + t_w + ": " + elem.style.width);
 
-					var cur_w = jQuery.css(this,"width");
+					var cur_w = jQuery.css(elem,"width");
 
-					ok(this.style.width != "" || cur_w == t_w, "Width should be explicitly set to " + t_w + ", is instead: " + cur_w);
+					ok(elem.style.width != "" || cur_w == t_w, "Width should be explicitly set to " + t_w + ", is instead: " + cur_w);
 				}
 
 				if ( t_h.constructor == Number ) {
-					equals(this.style.height, t_h + "px", "Final height should be " + t_h + ": " + this.style.height);
+					equals(elem.style.height, t_h + "px", "Final height should be " + t_h + ": " + elem.style.height);
 
-					var cur_h = jQuery.css(this,"height");
+					var cur_h = jQuery.css(elem,"height");
 
-					ok(this.style.height != "" || cur_h == t_h, "Height should be explicitly set to " + t_h + ", is instead: " + cur_w);
+					ok(elem.style.height != "" || cur_h == t_h, "Height should be explicitly set to " + t_h + ", is instead: " + cur_w);
 				}
 
 				if ( t_h == "show" ) {
-					var old_h = jQuery.css(this, "height");
-					jQuery(this).append("<br/>Some more text<br/>and some more...");
+					var old_h = jQuery.css(elem, "height");
+					jQuery(elem).append("<br/>Some more text<br/>and some more...");
 
 					if ( /Auto/.test( fn ) ) {
-						notEqual(jQuery.css(this, "height"), old_h, "Make sure height is auto.");
+						notEqual(jQuery.css(elem, "height"), old_h, "Make sure height is auto.");
 					} else {
-						equals(jQuery.css(this, "height"), old_h, "Make sure height is not auto.");
+						equals(jQuery.css(elem, "height"), old_h, "Make sure height is not auto.");
 					}
 				}
 
 				// manually remove generated element
-				jQuery(this).remove();
+				jQuery(elem).remove();
 
 				start();
 			});