From 00f96de5d65ef5a2dfbc62ab5d2b369b5a7392cf Mon Sep 17 00:00:00 2001
From: Malcolm Tredinnick <malcolm.tredinnick@gmail.com>
Date: Tue, 5 Feb 2008 23:41:48 +0000
Subject: [PATCH] Tweaked [7082] and [7084] a little bit to also allow comment
 nodes prior to the extends tag.

This would be little less fiddly if we knew nodelist were always of type
NodeList, but they could be normal lists. Or if we merged successive TextNodes,
instead of appending them. Something to think about going forwards.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@7089 bcc190cf-cafb-0310-a4f2-bffc1f526a37
---
 django/template/__init__.py    | 15 ++++++++++++---
 django/template/loader_tags.py | 14 +++++---------
 2 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/django/template/__init__.py b/django/template/__init__.py
index c53d400f3c..29daa76eac 100644
--- a/django/template/__init__.py
+++ b/django/template/__init__.py
@@ -289,9 +289,14 @@ class Parser(object):
         return NodeList()
 
     def extend_nodelist(self, nodelist, node, token):
-        if (node.must_be_first and nodelist and
-                (not isinstance(nodelist[0], TextNode) or len(nodelist) > 2)):
-            raise TemplateSyntaxError("%r must be the first tag in the template." % node)
+        if node.must_be_first and nodelist:
+            try:
+                if nodelist.contains_nontext:
+                    raise AttributeError
+            except AttributeError:
+                raise TemplateSyntaxError("%r must be the first tag in the template." % node)
+        if isinstance(nodelist, NodeList) and not isinstance(node, TextNode):
+            nodelist.contains_nontext = True
         nodelist.append(node)
 
     def enter_command(self, command, token):
@@ -732,6 +737,10 @@ class Node(object):
         return nodes
 
 class NodeList(list):
+    # Set to True the first time a non-TextNode is inserted by
+    # extend_nodelist().
+    contains_nontext = False
+
     def render(self, context):
         bits = []
         for node in self:
diff --git a/django/template/loader_tags.py b/django/template/loader_tags.py
index 716e475807..00ae99bbf9 100644
--- a/django/template/loader_tags.py
+++ b/django/template/loader_tags.py
@@ -69,14 +69,10 @@ class ExtendsNode(Node):
 
     def render(self, context):
         compiled_parent = self.get_parent(context)
-        if len(compiled_parent.nodelist) > 1:
-            n0, n1 = compiled_parent.nodelist[:2]
-        else:
-            n0, n1 = compiled_parent.nodelist[0], None
-        parent_is_child = (isinstance(n0, ExtendsNode) or
-                (isinstance(n0, TextNode) and isinstance(n1, ExtendsNode)))
-        if parent_is_child:
-            extend_node = int(not isinstance(n0, ExtendsNode))
+        pos = 0
+        while isinstance(compiled_parent.nodelist[pos], TextNode):
+            pos += 1
+        parent_is_child = isinstance(compiled_parent.nodelist[pos], ExtendsNode)
         parent_blocks = dict([(n.name, n) for n in compiled_parent.nodelist.get_nodes_by_type(BlockNode)])
         for block_node in self.nodelist.get_nodes_by_type(BlockNode):
             # Check for a BlockNode with this node's name, and replace it if found.
@@ -88,7 +84,7 @@ class ExtendsNode(Node):
                 # add this BlockNode to the parent's ExtendsNode nodelist, so
                 # it'll be checked when the parent node's render() is called.
                 if parent_is_child:
-                    compiled_parent.nodelist[extend_node].nodelist.append(block_node)
+                    compiled_parent.nodelist[pos].nodelist.append(block_node)
             else:
                 # Keep any existing parents and add a new one. Used by BlockNode.
                 parent_block.parent = block_node.parent