diff --git a/test/jquery.uls.test.js b/test/jquery.uls.test.js
index 0183e2f..5a645c4 100644
--- a/test/jquery.uls.test.js
+++ b/test/jquery.uls.test.js
@@ -51,6 +51,24 @@
 		return result;
 	};
 
+	/*
+	 * Runs over all languages and checks that all redirects point to a language.
+	 * There's no reason to have double redirects.
+	 */
+	var doubleRedirects = function () {
+		var result = [];
+
+		for ( var language in $.uls.data.languages ) {
+			var target = $.uls.data.isRedirect( language );
+
+			if ( target && $.uls.data.isRedirect( target ) ) {
+				result.push( language );
+			}
+		}
+
+		return result;
+	};
+
 	/*
 	 * Runs over all script codes mentioned in langdb and checks whether
 	 * they have something that looks like an autonym.
@@ -71,7 +89,7 @@
 		assert.ok( $.fn.uls, "$.fn.uls is defined" );
 	} );
 
-	test( "-- $.uls.data testing", 40, function ( assert ) {
+	test( "-- $.uls.data testing", 41, function ( assert ) {
 
 		assert.strictEqual( $.uls.data.isRedirect( 'sr-ec' ), 'sr-cyrl', "'sr-ec' is a redirect to 'sr-cyrl'" );
 		var autonyms = $.uls.data.getAutonyms();
@@ -82,7 +100,9 @@
 		// This test assumes that we don't want any scripts to be in the 'Other'
 		// group. Actually, this may become wrong some day.
 		assert.deepEqual( orphanScripts(), [], 'All scripts belong to script groups.' );
+
 		assert.deepEqual( badRedirects(), [], 'All redirects have valid targets.' );
+		assert.deepEqual( doubleRedirects(), [], 'There are no double redirects.' );
 		assert.deepEqual( languagesWithoutAutonym(), [], 'All languages have autonyms.' );
 
 		assert.strictEqual(