Makes sure jsonp callback is not left in the global namespace in case of an...

Makes sure jsonp callback is not left in the global namespace in case of an early abort (beforeSend). Unit test added.

src/ajax/jsonp.js

@@ -12,9 +12,9 @@ jQuery.ajaxSetup({
 });
 
 // Detect, normalize options and install callbacks for jsonp requests
-jQuery.ajaxPrefilter( "json jsonp", function( s, originalSettings, dataIsString /* internal */ ) {
+jQuery.ajaxPrefilter( "json jsonp", function( s, originalSettings, jXHR ) {
 
-	dataIsString = ( typeof s.data === "string" );
+	var dataIsString = ( typeof s.data === "string" );
 
 	if ( s.dataTypes[ 0 ] === "jsonp" ||
 		originalSettings.jsonpCallback ||
@@ -28,7 +28,15 @@ jQuery.ajaxPrefilter( "json jsonp", function( s, originalSettings, dataIsString
 			previous = window[ jsonpCallback ],
 			url = s.url,
 			data = s.data,
-			replace = "$1" + jsonpCallback + "$2";
+			replace = "$1" + jsonpCallback + "$2",
+			cleanUp = function() {
+				// Set callback back to previous value
+				window[ jsonpCallback ] = previous;
+				// Call if it was a function and we have a response
+				if ( responseContainer && jQuery.isFunction( previous ) ) {
+					window[ jsonpCallback ]( responseContainer[ 0 ] );
+				}
+			};
 
 		if ( s.jsonp !== false ) {
 			url = url.replace( jsre, replace );
@@ -46,32 +54,17 @@ jQuery.ajaxPrefilter( "json jsonp", function( s, originalSettings, dataIsString
 		s.url = url;
 		s.data = data;
 
+		// Install callback
 		window[ jsonpCallback ] = function( response ) {
 			responseContainer = [ response ];
 		};
 
-		s.complete = [ function() {
-
-			// Set callback back to previous value
-			window[ jsonpCallback ] = previous;
-
-			// Call if it was a function and we have a response
-			if ( previous) {
-				if ( responseContainer && jQuery.isFunction( previous ) ) {
-					window[ jsonpCallback ] ( responseContainer[ 0 ] );
-				}
-			} else {
-				// else, more memory leak avoidance
-				try{
-					delete window[ jsonpCallback ];
-				} catch( e ) {}
-			}
-
-		}, s.complete ];
+		// Install cleanUp function
+		jXHR.then( cleanUp, cleanUp );
 
 		// Use data converter to retrieve json after script execution
 		s.converters["script json"] = function() {
-			if ( ! responseContainer ) {
+			if ( !responseContainer ) {
 				jQuery.error( jsonpCallback + " was not called" );
 			}
 			return responseContainer[ 0 ];

test/unit/ajax.js

@@ -1221,10 +1221,10 @@ test("jQuery.getScript(String, Function) - no callback", function() {
 jQuery.each( [ "Same Domain", "Cross Domain" ] , function( crossDomain , label ) {
 
 	test("jQuery.ajax() - JSONP, " + label, function() {
-		expect(16);
+		expect(20);
 
 		var count = 0;
-		function plus(){ if ( ++count == 16 ) start(); }
+		function plus(){ if ( ++count == 18 ) start(); }
 
 		stop();
 
@@ -1364,6 +1364,38 @@ jQuery.each( [ "Same Domain", "Cross Domain" ] , function( crossDomain , label )
 			}
 		});
 
+		jQuery.ajax({
+			url: "data/jsonp.php",
+			dataType: "jsonp",
+			crossDomain: crossDomain,
+			jsonpCallback: "functionToCleanUp",
+			success: function(data){
+				ok( data.data, "JSON results returned (GET, custom callback name to be cleaned up)" );
+				strictEqual( window.functionToCleanUp, undefined, "Callback was removed (GET, custom callback name to be cleaned up)" );
+				plus();
+				var xhr;
+				jQuery.ajax({
+					url: "data/jsonp.php",
+					dataType: "jsonp",
+					crossDomain: crossDomain,
+					jsonpCallback: "functionToCleanUp",
+					beforeSend: function( jXHR ) {
+						xhr = jXHR;
+						return false;
+					}
+				});
+				xhr.error(function() {
+					ok( true, "Ajax error JSON (GET, custom callback name to be cleaned up)" );
+					strictEqual( window.functionToCleanUp, undefined, "Callback was removed after early abort (GET, custom callback name to be cleaned up)" );
+					plus();
+				});
+			},
+			error: function(data){
+				ok( false, "Ajax error JSON (GET, custom callback name to be cleaned up)" );
+				plus();
+			}
+		});
+
 		jQuery.ajax({
 			type: "POST",
 			url: "data/jsonp.php",
@@ -1647,7 +1679,7 @@ test("jQuery.post - data", 3, function() {
 			jQuery( 'math', xml ).each( function() {
 				equals( jQuery( 'calculation', this ).text(), '5-2', 'Check for XML' );
 				equals( jQuery( 'result', this ).text(), '3', 'Check for XML' );
-			})
+			});
 		}),
 
 		jQuery.ajax({