added support for {{ _self }} to provide an upgrade path from 1.x to 2.0

CHANGELOG

@@ -1,5 +1,6 @@
 * 1.29.0 (2016-XX-XX)
 
+ * added support for {{ _self }} to provide an upgrade path from 1.x to 2.0 (replaces {{ _self.templateName }})
  * deprecated silent display of undefined blocks
  * deprecated support for mbstring.func_overload != 0
 

doc/deprecated.rst

@@ -181,7 +181,8 @@ Globals
   current ``Twig_Template`` instance is deprecated; most usages only need the
   current template name, which will continue to work in Twig 2.0. In Twig 2.0,
   ``_self`` returns the current template name instead of the current
-  ``Twig_Template`` instance.
+  ``Twig_Template`` instance. If you are using ``{{ _self.templateName }}``,
+  just replace it with ``{{ _self }}``.
 
 Miscellaneous
 -------------

lib/Twig/Template.php

@@ -39,6 +39,14 @@ abstract class Twig_Template implements Twig_TemplateInterface
         $this->env = $env;
     }
 
+    /**
+     * @internal this method will be removed in 2.0 and is only used internally to provide an upgrade path from 1.x to 2.0
+     */
+    public function __toString()
+    {
+        return $this->getTemplateName();
+    }
+
     /**
      * Returns the template name.
      *

test/Twig/Tests/Fixtures/expressions/_self.test

@@ -0,0 +1,8 @@
+--TEST--
+_self returns the template name
+--TEMPLATE--
+{{ _self }}
+--DATA--
+return array()
+--EXPECT--
+index.twig