Fix errors in django 1.8 and below

compressor/offline/django.py

@@ -18,8 +18,9 @@ def handle_extendsnode(extendsnode, context):
     all blocks tags with the nodes of appropriate blocks.
     Also handles {{ block.super }} tags.
     """
-    context.render_context.setdefault(BLOCK_CONTEXT_KEY, BlockContext())
-    block_context = context.render_context.get(BLOCK_CONTEXT_KEY)
+    if BLOCK_CONTEXT_KEY not in context.render_context:
+        context.render_context[BLOCK_CONTEXT_KEY] = BlockContext()
+    block_context = context.render_context[BLOCK_CONTEXT_KEY]
     blocks = dict((n.name, n) for n in
                   extendsnode.nodelist.get_nodes_by_type(BlockNode))
     block_context.add_blocks(blocks)

compressor/tests/test_offline.py

@@ -7,8 +7,9 @@ import unittest
 from importlib import import_module
 
 from mock import patch
-from unittest import SkipTest
+from unittest import SkipTest, skipIf
 
+from django import VERSION as DJANGO_VERSION
 from django.core.management.base import CommandError
 from django.template import Template, Context
 from django.test import TestCase
@@ -632,6 +633,7 @@ class OfflineCompressComplexTestCase(OfflineTestCaseMixin, TestCase):
         self.assertEqual(rendered_template, ''.join(result) + '\n')
 
 
+@skipIf(DJANGO_VERSION[0] <= 1 and DJANGO_VERSION[1] < 9, "Needs Django >= 1.9, recursive templates were fixed in Django 1.9")
 class OfflineCompressExtendsRecursionTestCase(OfflineTestCaseMixin, TestCase):
     """
         Test that templates extending templates with the same name