From 6bfd864ff2a7d4903d485ee40094a1315da8221b Mon Sep 17 00:00:00 2001
From: Tommy Beadle <tbeadle@arbor.net>
Date: Mon, 13 Apr 2015 10:57:44 -0400
Subject: [PATCH] Fixed #24603 -- Allowed Context.update() to be used as a
 context manager.

---
 django/template/context.py           |  3 +--
 docs/ref/templates/api.txt           | 15 +++++++++++++++
 docs/releases/1.9.txt                |  3 +++
 tests/template_tests/test_context.py | 13 +++++++++++++
 4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/django/template/context.py b/django/template/context.py
index 2434b31a683..778a83d7a3e 100644
--- a/django/template/context.py
+++ b/django/template/context.py
@@ -171,8 +171,7 @@ class Context(BaseContext):
         "Pushes other_dict to the stack of dictionaries in the Context"
         if not hasattr(other_dict, '__getitem__'):
             raise TypeError('other_dict must be a mapping (dictionary-like) object.')
-        self.dicts.append(other_dict)
-        return other_dict
+        return ContextDict(self, other_dict)
 
 
 class RenderContext(BaseContext):
diff --git a/docs/ref/templates/api.txt b/docs/ref/templates/api.txt
index 077330f6ce5..5e56eff1d4f 100644
--- a/docs/ref/templates/api.txt
+++ b/docs/ref/templates/api.txt
@@ -497,6 +497,21 @@ the stack instead of an empty one.
     >>> c['foo']
     'first level'
 
+Like ``push()``, you can use ``update()`` as a context manager to ensure a
+matching ``pop()`` is called.
+
+    >>> c = Context()
+    >>> c['foo'] = 'first level'
+    >>> with c.update({'foo': 'second level'}):
+    ...     c['foo']
+    'second level'
+    >>> c['foo']
+    'first level'
+
+.. versionadded:: 1.9
+
+    The ability to use ``update()`` as a context manager was added.
+
 Using a ``Context`` as a stack comes in handy in :ref:`some custom template
 tags <howto-writing-custom-template-tags>`.
 
diff --git a/docs/releases/1.9.txt b/docs/releases/1.9.txt
index 47c2bc98bc9..25da6978ba8 100644
--- a/docs/releases/1.9.txt
+++ b/docs/releases/1.9.txt
@@ -211,6 +211,9 @@ Templates
 * The :ttag:`firstof` template tag supports storing the output in a variable
   using 'as'.
 
+* :meth:`Context.update() <django.template.Context.update>` can now be used as
+  a context manager.
+
 Requests and Responses
 ^^^^^^^^^^^^^^^^^^^^^^
 
diff --git a/tests/template_tests/test_context.py b/tests/template_tests/test_context.py
index 9c23a38af23..f7959e64158 100644
--- a/tests/template_tests/test_context.py
+++ b/tests/template_tests/test_context.py
@@ -21,6 +21,8 @@ class ContextTests(SimpleTestCase):
         self.assertEqual(c["a"], 1)
         self.assertEqual(c.get("foo", 42), 42)
 
+    def test_push_context_manager(self):
+        c = Context({"a": 1})
         with c.push():
             c['a'] = 2
             self.assertEqual(c['a'], 2)
@@ -30,6 +32,17 @@ class ContextTests(SimpleTestCase):
             self.assertEqual(c['a'], 3)
         self.assertEqual(c['a'], 1)
 
+    def test_update_context_manager(self):
+        c = Context({"a": 1})
+        with c.update({}):
+            c['a'] = 2
+            self.assertEqual(c['a'], 2)
+        self.assertEqual(c['a'], 1)
+
+        with c.update({'a': 3}):
+            self.assertEqual(c['a'], 3)
+        self.assertEqual(c['a'], 1)
+
     def test_setdefault(self):
         c = Context()