Add extended attributes to IdlCallbackFunction

third_party/WebKit/Source/bindings/scripts/idl_definitions.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 155 matching lines @@
 
 
 ################################################################################
 # Callback Functions
 ################################################################################
 
 class IdlCallbackFunction(TypedObject):
     def __init__(self, idl_name, node):
         children = node.GetChildren()
         num_children = len(children)
-        if num_children != 2:
-            raise ValueError('Expected 2 children, got %s' % num_children)
-        type_node, arguments_node = children
+        self.extended_attributes = {}
+        if num_children == 2:
+            type_node, arguments_node = children
+        elif num_children == 3:
+            type_node, arguments_node, extended_attributes_node = children
+            self.extended_attributes = (
+                ext_attributes_node_to_extended_attributes(idl_name, extended_attributes_node))
+        else:
+            raise ValueError('Expected 2 or 3 children, got %s' % num_children)

[haraken, 2016/08/30 05:27:57]

I'd prefer the following pattern:

if num_children < 2 or num_children > 3:
  raise ValueError(...)
type_node = children[0]
arguments_node = children[1]
if num_children == 3:
  self.extended_attributes = ext_attributes_node_to_extended_attributes(...)
else:
  self.extended_attributes = {}


c.f., see how the IdlConstant class is implemented.

[Yuki, 2016/08/30 05:49:11]

Lisa's code looks more Python's way than haraken's suggestion, and easier for me
to read.  Although it's also reasonable to keep consistency with the rest of
lines in this file.

[lkawai, 2016/08/30 05:57:01]

Done.

[lkawai, 2016/08/30 05:57:01]

Acknowledged.

         arguments_node_class = arguments_node.GetClass()
         if arguments_node_class != 'Arguments':
             raise ValueError('Expected Arguments node, got %s' % arguments_node_class)
 
         self.idl_name = idl_name
         self.name = node.GetName()
         self.idl_type = type_node_to_type(type_node)
         self.arguments = arguments_node_to_arguments(idl_name, arguments_node)
 
     def accept(self, visitor):
@@ skipping 930 matching lines @@
         self.visit_typed_object(argument)
 
     def visit_iterable(self, iterable):
         self.visit_typed_object(iterable)
 
     def visit_maplike(self, maplike):
         self.visit_typed_object(maplike)
 
     def visit_setlike(self, setlike):
         self.visit_typed_object(setlike)