Ticket #5908: resetcycle.diff

django/template/defaulttags.py

@@ -41 +41 @@
     def __init__(self, cyclevars, variable_name=None):
         self.cycle_iter = itertools_cycle(cyclevars)
         self.variable_name = variable_name
+        self.cyclevars = cyclevars
 
-    def render(self, context):
+    def render(self, context):        
+        if context.has_key('resetcycle'):
+            if context['resetcycle'] != None:
+                reset_name = context['resetcycle'][0]
+            else:
+                reset_name = None
+            
+            if self.variable_name == reset_name:
+                self.cycle_iter = itertools_cycle(self.cyclevars)
+                for d in context.dicts:
+                    if 'resetcycle' in d:
+                        del(d['resetcycle'])
         value = self.cycle_iter.next()
         value = Variable(value).resolve(context)
         if self.variable_name:
             context[self.variable_name] = value
         return value
 
+class ResetCycleNode(Node):
+    def __init__(self, variable_name=None):
+        self.variable_name = variable_name
+
+    def render(self, context):
+        context['resetcycle'] = self.variable_name
+        return ''
+
 class DebugNode(Node):
     def render(self, context):
         from pprint import pformat
@@ -498 +518 @@
     return node
 cycle = register.tag(cycle)
 
+def resetcycle(parser, token):
+    """
+    Resets cycle tag.
+    
+    If argument is given, resets the cycle named argument, else resets last
+    non-named argument.
+    """
+    args = token.split_contents()
+    
+    if len(args) > 2:
+        raise TemplateSyntaxError("'resetcycle' tag accepts maximum of one argument.")
+    
+    if len(args) == 2:
+        # {% resetcycle foo %} case.
+        name = args[1]
+        if not hasattr(parser, '_namedCycleNodes'):
+            raise TemplateSyntaxError("No named cycles in template."
+                                      " '%s' is not defined" % name)
+        if not name in parser._namedCycleNodes:
+            raise TemplateSyntaxError("Named cycle '%s' does not exist" % name)
+        return ResetCycleNode(args[1:])
+    return ResetCycleNode()
+resetcycle = register.tag(resetcycle)
+
 def debug(parser, token):
     """
     Outputs a whole load of debugging information, including the current