don't render templates if the template tag is blank

scribbler/templatetags/scribbler_tags.py

@@ -71,10 +71,7 @@ def render(self, context):
             else:
                 scribble_template = template.Template(self.raw)
         scribble_context = build_scribble_context(scribble)
-        content = scribble_template.render(scribble_context, request)
-        wrapper_template = template.loader.get_template('scribbler/scribble-wrapper.html')
         context['scribble'] = scribble
-        context['rendered_scribble'] = content
         user = context.get('user', None)
         show_controls = False
         can_edit = False
@@ -92,8 +89,13 @@ def render(self, context):
         context['can_edit_scribble'] = can_edit
         context['can_delete_scribble'] = can_delete
         context['raw_content'] = self.raw
+        if not bool(scribble.content.strip()) and not (can_edit or can_add):
+            return "<div></div>"  # Don't bother to render blank scribble
+        content = scribble_template.render(scribble_context, request)
+        context['rendered_scribble'] = content
         # render() takes a dict, so we have to extract the context dict from the object
         context_data = context.dicts[-1]
+        wrapper_template = template.loader.get_template('scribbler/scribble-wrapper.html')
         return wrapper_template.render(context_data, request)