Objects with length properties weren't getting serialized properly by jQuery.param(). Fixes #5862.

Author: jeresig

src/ajax.js

@@ -603,20 +603,13 @@ jQuery.extend({
 	// Serialize an array of form elements or a set of
 	// key/values into a query string
 	param: function( a, traditional ) {
-		
 		var s = [];
 
 		// Set traditional to true for jQuery <= 1.3.2 behavior.
 		if ( traditional === undefined ) {
 			traditional = jQuery.ajaxSettings.traditional;
 		}
 
-		function add( key, value ) {
-			// If value is a function, invoke it and return its value
-			value = jQuery.isFunction(value) ? value() : value;
-			s[ s.length ] = encodeURIComponent(key) + "=" + encodeURIComponent(value);
-		}
-		
 		// If an array was passed in, assume that it is an array of form elements.
 		if ( jQuery.isArray(a) || a.jquery ) {
 			// Serialize the form elements
@@ -627,41 +620,49 @@ jQuery.extend({
 		} else {
 			// If traditional, encode the "old" way (the way 1.3.2 or older
 			// did it), otherwise encode params recursively.
-			jQuery.each( a, function buildParams( prefix, obj ) {
-				
-				if ( jQuery.isArray(obj) ) {
-					// Serialize array item.
-					jQuery.each( obj, function( i, v ) {
-						if ( traditional ) {
-							// Treat each array item as a scalar.
-							add( prefix, v );
-						} else {
-							// If array item is non-scalar (array or object), encode its
-							// numeric index to resolve deserialization ambiguity issues.
-							// Note that rack (as of 1.0.0) can't currently deserialize
-							// nested arrays properly, and attempting to do so may cause
-							// a server error. Possible fixes are to modify rack's
-							// deserialization algorithm or to provide an option or flag
-							// to force array serialization to be shallow.
-							buildParams( prefix + "[" + ( typeof v === "object" || jQuery.isArray(v) ? i : "" ) + "]", v );
-						}
-					});
-					
-				} else if ( !traditional && obj != null && typeof obj === "object" ) {
-					// Serialize object item.
-					jQuery.each( obj, function( k, v ) {
-						buildParams( prefix + "[" + k + "]", v );
-					});
-					
-				} else {
-					// Serialize scalar item.
-					add( prefix, obj );
-				}
-			});
+			for ( var prefix in a ) {
+				buildParams( prefix, a[prefix] );
+			}
 		}
-		
+
 		// Return the resulting serialization
 		return s.join("&").replace(r20, "+");
-	}
 
+		function buildParams( prefix, obj ) {
+			if ( jQuery.isArray(obj) ) {
+				// Serialize array item.
+				jQuery.each( obj, function( i, v ) {
+					if ( traditional ) {
+						// Treat each array item as a scalar.
+						add( prefix, v );
+					} else {
+						// If array item is non-scalar (array or object), encode its
+						// numeric index to resolve deserialization ambiguity issues.
+						// Note that rack (as of 1.0.0) can't currently deserialize
+						// nested arrays properly, and attempting to do so may cause
+						// a server error. Possible fixes are to modify rack's
+						// deserialization algorithm or to provide an option or flag
+						// to force array serialization to be shallow.
+						buildParams( prefix + "[" + ( typeof v === "object" || jQuery.isArray(v) ? i : "" ) + "]", v );
+					}
+				});
+					
+			} else if ( !traditional && obj != null && typeof obj === "object" ) {
+				// Serialize object item.
+				jQuery.each( obj, function( k, v ) {
+					buildParams( prefix + "[" + k + "]", v );
+				});
+					
+			} else {
+				// Serialize scalar item.
+				add( prefix, obj );
+			}
+		}
+
+		function add( key, value ) {
+			// If value is a function, invoke it and return its value
+			value = jQuery.isFunction(value) ? value() : value;
+			s[ s.length ] = encodeURIComponent(key) + "=" + encodeURIComponent(value);
+		}
+	}
 });

test/unit/ajax.js

@@ -979,6 +979,19 @@ test("jQuery.getJSON(String, Function) - JSON object with absolute url to local
 	});
 });
 
+test("jQuery.post - data", function() {
+	expect(2);
+	stop();
+
+	jQuery.post(url("data/name.php"), {xml: "5-2", length: 3}, function(xml){
+		jQuery('math', xml).each(function() {
+			equals( jQuery('calculation', this).text(), '5-2', 'Check for XML' );
+			equals( jQuery('result', this).text(), '3', 'Check for XML' );
+		});
+		start();
+	});
+});
+
 test("jQuery.post(String, Hash, Function) - simple with xml", function() {
 	expect(4);
 	stop();