diff -r 000000000000 -r 6474c204b198 js/src/tests/test262/ch12/12.5/S12.5_A12_T1.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/test262/ch12/12.5/S12.5_A12_T1.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,58 @@
+// Copyright 2009 the Sputnik authors.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/**
+ * Embedded "if/else" constructions are allowed
+ *
+ * @path ch12/12.5/S12.5_A12_T1.js
+ * @description Using embedded "if/else" into "if/else" constructions
+ */
+
+//CHECK# 1
+if(true)
+  if (false)
+    $ERROR('#1.1: At embedded "if/else" constructions engine must select right branches');
+  else
+    ;
+else 
+  if (true)
+    $ERROR('#1.2: At embedded "if/else" constructions engine must select right branches');
+  else
+    $ERROR('#1.3: At embedded "if/else" constructions engine must select right branches');
+
+//CHECK# 2
+if(true)
+  if (true)
+    ;
+  else
+    $ERROR('#2.1: At embedded "if/else" constructions engine must select right branches');
+else 
+  if (true)
+    $ERROR('#2.2: At embedded "if/else" constructions engine must select right branches');
+  else
+    $ERROR('#2.3: At embedded "if/else" constructions engine must select right branches');
+
+//CHECK# 3
+if(false)
+  if (true)
+    $ERROR('#3.1: At embedded "if/else" constructions engine must select right branches');
+  else
+    $ERROR('#3.2: At embedded "if/else" constructions engine must select right branches');
+else 
+  if (true)
+    ;
+  else
+    $ERROR('#3.3: At embedded "if/else" constructions engine must select right branches');
+
+//CHECK# 4
+if(false)
+  if (true)
+    $ERROR('#4.1: At embedded "if/else" constructions engine must select right branches');
+  else
+    $ERROR('#4.2: At embedded "if/else" constructions engine must select right branches');
+else 
+  if (false)
+    $ERROR('#4.3: At embedded "if/else" constructions engine must select right branches');
+  else
+    ;
+