Fixes #8138. Access to document.location is made only once at load ti…

…me and if it fails (throwing an exception in IE when document.domain is already set), we use the href of an A element instead.

src/ajax.js

@@ -34,7 +34,22 @@ var r20 = /%20/g,
 	 * 2) the catchall symbol "*" can be used
 	 * 3) selection will start with transport dataType and THEN go to "*" if needed
 	 */
-	transports = {};
+	transports = {},
+
+	// Stored document location array
+	ajaxLocation;
+
+// #8138, IE may throw an exception when accessing
+// a field from document.location if document.domain has been set
+try {
+	ajaxLocation = document.location.href;
+} catch( e ) {
+	// Use the href attribute of an A element
+	// since IE will modify it given document.location
+	ajaxLocation = document.createElement( "a" );
+	ajaxLocation.href = "";
+	ajaxLocation = ajaxLocation.href;
+}
 
 // Base "constructor" for jQuery.ajaxPrefilter and jQuery.ajaxTransport
 function addToPrefiltersOrTransports( structure ) {
@@ -260,7 +275,7 @@ jQuery.extend({
 	},
 
 	ajaxSettings: {
-		url: location.href,
+		url: ajaxLocation,
 		global: true,
 		type: "GET",
 		contentType: "application/x-www-form-urlencoded",
@@ -361,8 +376,6 @@ jQuery.extend({
 			// timeout handle
 			timeoutTimer,
 			// Cross-domain detection vars
-			loc = document.location,
-			protocol = loc.protocol || "http:",
 			parts,
 			// The jqXHR state
 			state = 0,
@@ -549,7 +562,7 @@ jQuery.extend({
 		// Remove hash character (#7531: and string promotion)
 		// Add protocol if not provided (#5866: IE7 issue with protocol-less urls)
 		// We also use the url parameter if available
-		s.url = ( "" + ( url || s.url ) ).replace( rhash, "" ).replace( rprotocol, protocol + "//" );
+		s.url = ( "" + ( url || s.url ) ).replace( rhash, "" ).replace( rprotocol, ajaxLocation[ 1 ] + "//" );
 
 		// Extract dataTypes list
 		s.dataTypes = jQuery.trim( s.dataType || "*" ).toLowerCase().split( rspacesAjax );
@@ -558,9 +571,9 @@ jQuery.extend({
 		if ( !s.crossDomain ) {
 			parts = rurl.exec( s.url.toLowerCase() );
 			s.crossDomain = !!( parts &&
-				( parts[ 1 ] != protocol || parts[ 2 ] != loc.hostname ||
+				( parts[ 1 ] != ajaxLocation[ 1 ] || parts[ 2 ] != ajaxLocation[ 2 ] ||
 					( parts[ 3 ] || ( parts[ 1 ] === "http:" ? 80 : 443 ) ) !=
-						( loc.port || ( protocol === "http:" ? 80 : 443 ) ) )
+						( ajaxLocation[ 3 ] || ( ajaxLocation[ 1 ] === "http:" ? 80 : 443 ) ) )
 			);
 		}
 
@@ -717,6 +730,9 @@ jQuery.extend({
 	}
 });
 
+// Segment ajaxLocation into parts
+ajaxLocation = rurl.exec( ajaxLocation.toLowerCase() );
+
 function buildParams( prefix, obj, traditional, add ) {
 	if ( jQuery.isArray( obj ) && obj.length ) {
 		// Serialize array item.