added test for "php closures from lua" functionality

tests/013.phpt

@@ -0,0 +1,30 @@
+--TEST--
+PHP Closures from Lua
+--SKIPIF--
+<?php if (!extension_loaded("lua")) print "skip"; ?>
+--FILE--
+<?php 
+
+$l = new lua();
+$l->eval(<<<CODE
+function test(cb1)
+    local cb2 = cb1("called from lua")
+    cb2("returned from php")
+end
+CODE
+);
+
+try {
+    $l->test(function($msg) {
+        print "$msg";
+    
+        return function($msg) {
+            print "$msg";
+        };
+    });
+} catch(LuaException $e) {
+    echo $e->getMessage();
+}
+?>
+--EXPECTF--
+called from luareturned from php