Add test

diff --git a/tests/classes/this.phpt b/tests/classes/this.phpt
new file mode 100755 (executable)
index 0000000..1d9c623
--- /dev/null
+++ b/tests/classes/this.phpt
@@ -0,0 +1,54 @@
+--TEST--
+ZE2 $this cannot be exchanged
+--SKIPIF--
+<?php if (version_compare(zend_version(), '2.0.0-dev', '<')) die('skip ZendEngine 2 needed'); ?>
+--FILE--
+<?php
+
+/* please don't shorten this test. It shows what would happen if 
+ * the fatal error would have been a warning.
+ */
+class Foo
+{
+    function replace($other)
+    {
+       echo __METHOD__ . "\n";
+        $this = $other;
+        print $this->prop;
+        print $other->prop;
+    }
+
+    function indirect($other)
+    {
+       echo __METHOD__ . "\n";
+        $this = $other;
+        $result = $this = $other;
+        print $result->prop;
+        print $this->prop;
+    }
+
+    function retrieve(&$other)
+    {
+       echo __METHOD__ . "\n";
+       $other = $this;
+    }
+}
+
+$object = new Foo;
+$object->prop = "Hello\n";
+
+$other  = new Foo;
+$other->prop = "World\n";
+
+$object->replace($other);
+$object->indirect($other);
+
+print $object->prop; // still shows 'Hello'
+
+$object->retrieve($other);
+print $other->prop;  // shows 'Hello'
+
+?>
+===DONE===
+--EXPECTF--
+Fatal error: Cannot re-assign $this in %sthis.php on line %d