From c459292321568271346981caa8b135240ce3f485 Mon Sep 17 00:00:00 2001
From: Chris Somme <csomme@atlassian.com>
Date: Thu, 4 Aug 2016 14:26:58 -0700
Subject: [PATCH] Allow Context to take another Context instance in new

Related to https://code.djangoproject.com/ticket/24765. If a
context instance is passed into new the context instance is
appended to dicts. The flatten method fails on instances of Context
because BaseContext#__iter__ returns iterates of the dicts.

This change pulls the dicts over Context supplied in new

Conflicts:
	tests/template_tests/test_context.py
---
 django/template/context.py           |  4 +++-
 tests/template_tests/test_context.py | 15 ++++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/django/template/context.py b/django/template/context.py
index b563e526f202..bf2f64f3480c 100644
--- a/django/template/context.py
+++ b/django/template/context.py
@@ -36,7 +36,9 @@ def __init__(self, dict_=None):
     def _reset_dicts(self, value=None):
         builtins = {'True': True, 'False': False, 'None': None}
         self.dicts = [builtins]
-        if value is not None:
+        if isinstance(value, BaseContext):
+            self.dicts += value.dicts[1:]
+        elif value is not None:
             self.dicts.append(value)
 
     def __copy__(self):
diff --git a/tests/template_tests/test_context.py b/tests/template_tests/test_context.py
index 87b2016aa500..6659ae6403be 100644
--- a/tests/template_tests/test_context.py
+++ b/tests/template_tests/test_context.py
@@ -131,7 +131,7 @@ def test_flatten_context(self):
         a.update({'b': 4})
         a.update({'c': 8})
 
-        self.assertEqual(a.flatten(), {
+        self.assertDictEqual(a.flatten(), {
             'False': False, 'None': None, 'True': True,
             'a': 2, 'b': 4, 'c': 8
         })
@@ -150,6 +150,19 @@ def test_flatten_context_with_context(self):
             'z': '8',
         })
 
+    def test_flatten_context_new_context(self):
+        """
+        Context.new with a Context argument should work.
+        """
+        a = Context({'a': 2})
+        b = a.new(Context({'b': 4}))
+        self.assertEqual(b.flatten(), {
+            'False': False,
+	    'None': None,
+	    'True': True,
+            'b': 4
+        })
+
     def test_context_comparable(self):
         """
         #21765 -- equality comparison should work