From 5b1bb40216ff452e34198345fdad63e2be370d2c Mon Sep 17 00:00:00 2001
From: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Thu, 20 Nov 2014 22:12:21 +0100
Subject: [PATCH] Added to each Context a reference to the Engine.

It's only available during the rendering.
---
 django/template/base.py    | 9 +++++++++
 django/template/context.py | 7 ++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/django/template/base.py b/django/template/base.py
index c8c9844a6a..ef611bc954 100644
--- a/django/template/base.py
+++ b/django/template/base.py
@@ -150,11 +150,19 @@ class Template(object):
 
     def render(self, context):
         "Display stage -- can be called many times"
+        # Set engine attribute here to avoid changing the signature of either
+        # Context.__init__ or Node.render. The engine is set only on the first
+        # call to render. Further calls e.g. for includes don't override it.
+        toplevel_render = context.engine is None
+        if toplevel_render:
+            context.engine = self.engine
         context.render_context.push()
         try:
             return self._render(context)
         finally:
             context.render_context.pop()
+            if toplevel_render:
+                context.engine = None
 
 
 def compile_string(template_string, origin):
@@ -1236,6 +1244,7 @@ class Library(object):
                         'current_app': context.current_app,
                         'use_l10n': context.use_l10n,
                         'use_tz': context.use_tz,
+                        'engine': context.engine,
                     })
                     # Copy across the CSRF token, if present, because
                     # inclusion tags are often used for forms, and we need
diff --git a/django/template/context.py b/django/template/context.py
index 5d66dd19fd..e48cfaef3b 100644
--- a/django/template/context.py
+++ b/django/template/context.py
@@ -121,11 +121,12 @@ class BaseContext(object):
 class Context(BaseContext):
     "A stack container for variable context"
     def __init__(self, dict_=None, autoescape=True, current_app=None,
-            use_l10n=None, use_tz=None):
+            use_l10n=None, use_tz=None, engine=None):
         self.autoescape = autoescape
         self.current_app = current_app
         self.use_l10n = use_l10n
         self.use_tz = use_tz
+        self.engine = engine
         self.render_context = RenderContext()
         super(Context, self).__init__(dict_)
 
@@ -186,9 +187,9 @@ class RequestContext(Context):
     using the "processors" keyword argument.
     """
     def __init__(self, request, dict_=None, processors=None, current_app=None,
-            use_l10n=None, use_tz=None):
+            use_l10n=None, use_tz=None, engine=None):
         Context.__init__(self, dict_, current_app=current_app,
-                use_l10n=use_l10n, use_tz=use_tz)
+                use_l10n=use_l10n, use_tz=use_tz, engine=engine)
         if processors is None:
             processors = ()
         else: