Fixed #6510 -- Refactored the way child nodes are found in template nodes to avoid potential inconsistencies. Thanks to SmileyChris for the patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12654 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/template/__init__.py

@@ -770,6 +770,7 @@ class Node(object):
     # Set this to True for nodes that must be first in the template (although
     # they can be preceded by text nodes.
     must_be_first = False
+    child_nodelists = ('nodelist',)
 
     def render(self, context):
         "Return the node rendered as a string"
@@ -783,8 +784,10 @@ class Node(object):
         nodes = []
         if isinstance(self, nodetype):
             nodes.append(self)
-        if hasattr(self, 'nodelist'):
-            nodes.extend(self.nodelist.get_nodes_by_type(nodetype))
+        for attr in self.child_nodelists:
+            nodelist = getattr(self, attr, None)
+            if nodelist:
+                nodes.extend(nodelist.get_nodes_by_type(nodetype))
         return nodes
 
 class NodeList(list):

django/template/defaulttags.py

@@ -97,6 +97,8 @@ class FirstOfNode(Node):
         return u''
 
 class ForNode(Node):
+    child_nodelists = ('nodelist_loop', 'nodelist_empty')
+
     def __init__(self, loopvars, sequence, is_reversed, nodelist_loop, nodelist_empty=None):
         self.loopvars, self.sequence = loopvars, sequence
         self.is_reversed = is_reversed
@@ -118,14 +120,6 @@ class ForNode(Node):
         for node in self.nodelist_empty:
             yield node
 
-    def get_nodes_by_type(self, nodetype):
-        nodes = []
-        if isinstance(self, nodetype):
-            nodes.append(self)
-        nodes.extend(self.nodelist_loop.get_nodes_by_type(nodetype))
-        nodes.extend(self.nodelist_empty.get_nodes_by_type(nodetype))
-        return nodes
-
     def render(self, context):
         if 'forloop' in context:
             parentloop = context['forloop']
@@ -181,6 +175,8 @@ class ForNode(Node):
         return nodelist.render(context)
 
 class IfChangedNode(Node):
+    child_nodelists = ('nodelist_true', 'nodelist_false')
+
     def __init__(self, nodelist_true, nodelist_false, *varlist):
         self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false
         self._last_seen = None
@@ -211,6 +207,8 @@ class IfChangedNode(Node):
         return ''
 
 class IfEqualNode(Node):
+    child_nodelists = ('nodelist_true', 'nodelist_false')
+
     def __init__(self, var1, var2, nodelist_true, nodelist_false, negate):
         self.var1, self.var2 = var1, var2
         self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false
@@ -227,6 +225,8 @@ class IfEqualNode(Node):
         return self.nodelist_false.render(context)
 
 class IfNode(Node):
+    child_nodelists = ('nodelist_true', 'nodelist_false')
+
     def __init__(self, var, nodelist_true, nodelist_false=None):
         self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false
         self.var = var
@@ -240,14 +240,6 @@ class IfNode(Node):
         for node in self.nodelist_false:
             yield node
 
-    def get_nodes_by_type(self, nodetype):
-        nodes = []
-        if isinstance(self, nodetype):
-            nodes.append(self)
-        nodes.extend(self.nodelist_true.get_nodes_by_type(nodetype))
-        nodes.extend(self.nodelist_false.get_nodes_by_type(nodetype))
-        return nodes
-
     def render(self, context):
         if self.var.eval(context):
             return self.nodelist_true.render(context)