bindings: Use an alias for @@iterator in certain declarations.

third_party/WebKit/Source/bindings/scripts/v8_interface.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 # coding=utf-8
 #
 # 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
@@ skipping 356 matching lines @@
     conditional_enabled_attributes = v8_attributes.filter_conditionally_enabled(attributes)
     has_conditional_attributes_on_prototype = any(  # pylint: disable=invalid-name
         attribute['on_prototype'] for attribute in conditional_enabled_attributes)
     context.update({
         'has_conditional_attributes_on_prototype':
             has_conditional_attributes_on_prototype,
         'conditionally_enabled_attributes': conditional_enabled_attributes,
     })
 
     # Methods
-    methods, iterator_method = methods_context(interface)
+    context.update(methods_context(interface))
+    methods = context['methods']
     context.update({
         'has_origin_safe_method_setter': any(method['is_cross_origin'] and not method['is_unforgeable']
             for method in methods),
-        'iterator_method': iterator_method,
-        'methods': methods,
         'conditionally_enabled_methods': v8_methods.filter_conditionally_enabled(methods, interface.is_partial),
     })
 
     # Window.idl in Blink has indexed properties, but the spec says Window
     # interface doesn't have indexed properties, instead the WindowProxy exotic
     # object has indexed properties.  Thus, Window interface must not support
     # iterators.
     has_array_iterator = (not interface.is_partial and
                           interface.has_indexed_elements and
                           interface.name != 'Window')
@@ skipping 107 matching lines @@
     return attributes
 
 
 def methods_context(interface):
     """Creates a list of Jinja template contexts for methods of an interface.
 
     Args:
         interface: An interface to create contexts for
 
     Returns:
-        A list of method contexts, and an iterator context if available or None
+        A dictionary with 3 keys:
+        'iterator_method': An iterator context if available or None.
+        'iterator_method_alias': A string that can also be used to refer to the
+                                 @@iterator symbol or None.
+        'methods': A list of method contexts.
     """
 
     methods = []
 
     if interface.original_interface:
         methods.extend([v8_methods.method_context(interface, operation, is_visible=False)
                         for operation in interface.original_interface.operations
                         if operation.name])
     methods.extend([v8_methods.method_context(interface, method)
                     for method in interface.operations
@@ skipping 24 matching lines @@
         argument.idl_type = idl_type
         argument.name = name
         argument.is_optional = is_optional
         if extended_attributes:
             argument.extended_attributes.update(extended_attributes)
         return argument
 
     # iterable<>, maplike<> and setlike<>
     iterator_method = None
 
+    # Depending on the declaration, @@iterator may be a synonym for e.g.
+    # 'entries' or 'values'.
+    iterator_method_alias = None
+
     # FIXME: support Iterable in partial interfaces. However, we don't
     # need to support iterator overloads between interface and
     # partial interface definitions.
     # http://heycam.github.io/webidl/#idl-overloading
     if (not interface.is_partial and (
             interface.iterable or interface.maplike or interface.setlike or
             interface.has_indexed_elements)):
 
         used_extended_attributes = {}
 
@@ skipping 30 matching lines @@
             iterator_method = generated_iterator_method('iterator', implemented_as='GetIterator')
 
         if interface.iterable or interface.maplike or interface.setlike:
             non_overridable_methods = []
             overridable_methods = []
 
             is_value_iterator = interface.iterable and interface.iterable.key_type is None
 
             # For value iterators, the |entries|, |forEach|, |keys| and |values| are originally set
             # to corresponding properties in %ArrayPrototype%.
+            # For pair iterators and maplike declarations, |entries| is an alias for @@iterator
+            # itself. For setlike declarations, |values| is an alias for @@iterator.
             if not is_value_iterator:
+                if not interface.setlike:
+                    iterator_method_alias = 'entries'
+                    entries_or_values_method = generated_iterator_method('values')
+                else:
+                    iterator_method_alias = 'values'
+                    entries_or_values_method = generated_iterator_method('entries')
+
                 non_overridable_methods.extend([
                     generated_iterator_method('keys'),
-                    generated_iterator_method('values'),
-                    generated_iterator_method('entries'),
+                    entries_or_values_method,
 
                     # void forEach(Function callback, [Default=Undefined] optional any thisArg)
                     generated_method(IdlType('void'), 'forEach',
                                      arguments=[generated_argument(IdlType('Function'), 'callback'),
                                                 generated_argument(IdlType('any'), 'thisArg',
                                                                    is_optional=True,
                                                                    extended_attributes={'Default': 'Undefined'})],
                                      extended_attributes=forEach_extended_attributes),
                 ])
 
@@ skipping 106 matching lines @@
         # operation is a static operation) with identifier id on interface I and
         # with argument count 0.
         # 2. Return the length of the shortest argument list of the entries in S.
         # FIXME: This calculation doesn't take into account whether runtime
         # enabled overloads are actually enabled, so length may be incorrect.
         # E.g., [RuntimeEnabled=Foo] void f(); void f(long x);
         # should have length 1 if Foo is not enabled, but length 0 if it is.
         method['length'] = (method['overloads']['length'] if 'overloads' in method else
                             method['number_of_required_arguments'])
 
-    return methods, iterator_method
+    return {
+        'iterator_method': iterator_method,
+        'iterator_method_alias': iterator_method_alias,
+        'methods': methods,
+    }
 
 
 def reflected_name(constant_name):
     """Returns the name to use for the matching constant name in blink code.
 
     Given an all-uppercase 'CONSTANT_NAME', returns a camel-case
     'kConstantName'.
     """
     # Check for SHOUTY_CASE constants
     if constant_name.upper() != constant_name:
@@ skipping 667 matching lines @@
     extended_attributes = deleter.extended_attributes
     is_call_with_script_state = v8_utilities.has_extended_attribute_value(deleter, 'CallWith', 'ScriptState')
     is_ce_reactions = 'CEReactions' in extended_attributes
     return {
         'is_call_with_script_state': is_call_with_script_state,
         'is_ce_reactions': is_ce_reactions,
         'is_custom': 'Custom' in extended_attributes,
         'is_raises_exception': 'RaisesException' in extended_attributes,
         'name': cpp_name(deleter),
     }