IDL compiler: [Reflect] for getters (+ remove unnecessary WebCore::)

Source/bindings/scripts/unstable/v8_attributes.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 63 matching lines @@
         'is_keep_alive_for_gc': this_is_keep_alive_for_gc,
         'is_nullable': attribute.is_nullable,
         'is_static': attribute.is_static,
         'name': attribute.name,
         'v8_type': v8_types.v8_type(idl_type),
     }
     if has_extended_attribute(attribute, ('Custom', 'CustomGetter')):
         contents['is_custom_getter'] = True
         return contents, set()
 
-    cpp_value = getter_expression(interface, attribute, contents)
+    includes = set()
+    cpp_value = getter_expression(interface, attribute, contents, includes)
     # Normally we can inline the function call into the return statement to
     # avoid the overhead of using a Ref<> temporary, but for some cases
     # (nullable types, EventHandler, CachedAttribute, or if there are
     # exceptions), we need to use a local variable.
     # FIXME: check if compilers are smart enough to inline this, and if so,
     # always use a local variable (for readability and CG simplicity).
     if (attribute.is_nullable or
         idl_type == 'EventHandler' or
         'CachedAttribute' in extended_attributes):
         contents['cpp_value_original'] = cpp_value
         cpp_value = 'value'
     contents['cpp_value'] = cpp_value
 
     if this_is_keep_alive_for_gc:
         return_v8_value_statement = 'v8SetReturnValue(info, wrapper);'
-        includes = v8_types.includes_for_type(idl_type)
+        type_includes = v8_types.includes_for_type(idl_type)
         includes.add('bindings/v8/V8HiddenPropertyName.h')
     else:
-        return_v8_value_statement, includes = v8_types.v8_set_return_value(idl_type, cpp_value, callback_info='info', isolate='info.GetIsolate()', extended_attributes=extended_attributes, script_wrappable='imp')
+        return_v8_value_statement, type_includes = v8_types.v8_set_return_value(idl_type, cpp_value, callback_info='info', isolate='info.GetIsolate()', extended_attributes=extended_attributes, script_wrappable='imp')
+    includes.update(type_includes)
     contents['return_v8_value_statement'] = return_v8_value_statement
 
     if (idl_type == 'EventHandler' and
         interface.name in ['Window', 'WorkerGlobalScope'] and
         attribute.name == 'onerror'):
             includes.add('bindings/v8/V8ErrorHandler.h')
 
     # [CheckSecurityForNode]
     is_check_security_for_node = 'CheckSecurityForNode' in extended_attributes
     if is_check_security_for_node:
         includes.update(set(['bindings/v8/BindingSecurity.h',
         # FIXME: these should be added if [CheckSecurityForNode], [GetterRaisesException], or [RaisesException]
                              'bindings/v8/ExceptionMessages.h',
                              'bindings/v8/ExceptionState.h']))
 
         includes.add('bindings/v8/BindingSecurity.h')
     # [DeprecateAs]
     v8_utilities.generate_deprecate_as(attribute, contents, includes)
 
     contents.update({
         'is_activity_logging_getter': v8_utilities.has_activity_logging(attribute, includes, 'Getter'),  # [ActivityLogging=Access|Getter]
         'is_check_security_for_node': is_check_security_for_node,
     })
 
     return contents, includes
 
 
-def getter_expression(interface, attribute, contents):
-    this_getter_name = getter_name(interface, attribute)
-    arguments = v8_utilities.call_with_arguments(attribute, contents)
+def getter_expression(interface, attribute, contents, includes):
+    arguments = []
+    if 'Reflect' in attribute.extended_attributes:
+        getter_base_name = content_attribute_getter_base_name(attribute, includes, arguments)
+    else:
+        getter_base_name = uncapitalize(attribute.name)
+
+    if attribute.is_static:
+        getter_name = '%s::%s' % (interface.name, getter_base_name)
+    else:
+        getter_name = 'imp->%s' % getter_base_name
+
+    arguments.extend(v8_utilities.call_with_arguments(attribute, contents))
     if attribute.is_nullable:
         arguments.append('isNull')
     if attribute.data_type == 'EventHandler':
         arguments.append('isolatedWorldForIsolate(info.GetIsolate())')
-    return '%s(%s)' % (this_getter_name, ', '.join(arguments))
+    return '%s(%s)' % (getter_name, ', '.join(arguments))
 
 
-def getter_name(interface, attribute):
-    getter_method_name = uncapitalize(attribute.name)
-    if attribute.is_static:
-        return '%s::%s' % (interface.name, getter_method_name)
-    return 'imp->%s' % getter_method_name
+CONTENT_ATTRIBUTE_GETTER_NAMES = {

[haraken, 2013/10/15 02:14:30]

I don't fully understand what "content" means.

CONTENT_ATTRIBUTE_GETTER_NAMES => CPP_ATTRIBUTE_GETTER_NAMES ?

[Nils Barth (inactive), 2013/10/15 09:48:15]

The IDL attribute is reflecting an HTML attribute ("content attribute"), so the
getter is a getter for the underlying content attribute.

Sorry, forgot to link to docs:
https://sites.google.com/a/chromium.org/dev/blink/webidl/blink-idl-extended-a...
http://www.whatwg.org/specs/web-apps/current-work/multipage/common-dom-interf...

"Some IDL attributes are defined to reflect a particular content attribute."

"Content attribute" is a term in the HTML5 spec (WhatWG), meaning "HTML
attribute, not IDL attribute":
http://www.whatwg.org/specs/web-apps/current-work/multipage/infrastructure.ht...
"This specification refers to both HTML and XML attributes and IDL attributes,
often in the same context. When it is not clear which is being referred to, they
are referred to as content attributes for HTML and XML attributes, and IDL
attributes for those defined on IDL interfaces."

+    'boolean': 'fastHasAttribute',
+    'long': 'getIntegralAttribute',
+    'unsigned long': 'getUnsignedIntegralAttribute',
+}
+
+
+def content_attribute_getter_base_name(attribute, includes, arguments):

[haraken, 2013/10/15 02:14:30]

content_attribute_getter_base_name => cpp_attribute_getter_name ?

+    default_content_attribute_name = attribute.name.lower()
+    content_attribute_name = attribute.extended_attributes['Reflect'] or default_content_attribute_name

[haraken, 2013/10/15 02:14:30]

Nit: default_content_attribute_name is not necessary.

[Nils Barth (inactive), 2013/10/15 09:48:15]

Removed.

+
+    namespace = 'HTMLNames'  # FIXME: can be SVG too
+    includes.add('%s.h' % namespace)
+
+    if content_attribute_name in ['class', 'id', 'name']:

[haraken, 2013/10/15 02:14:30]

Add a comment:

  # For performance optimization.

[Nils Barth (inactive), 2013/10/15 09:48:15]

Done.

+        return 'get%sAttribute' % content_attribute_name.capitalize()
+
+    scoped_name = 'WebCore::%s::%sAttr' % (namespace, content_attribute_name)

[haraken, 2013/10/15 02:14:30]

Is WebCore:: necessary?

[Nils Barth (inactive), 2013/10/15 09:48:15]

Doesn't look like it!
Removed here and in Perl.

+    arguments.append(scoped_name)
+
+    idl_type = attribute.data_type
+    if idl_type in CONTENT_ATTRIBUTE_GETTER_NAMES:
+        return CONTENT_ATTRIBUTE_GETTER_NAMES[idl_type]
+    return 'fastGetAttribute'
 
 
 def is_keep_alive_for_gc(attribute):
     idl_type = attribute.data_type
     extended_attributes = attribute.extended_attributes
     return (
         'KeepAttributeAliveForGC' in extended_attributes or
         # For readonly attributes, for performance reasons we keep the attribute
         # wrapper alive while the owner wrapper is alive, because the attribute
         # never changes.
         (attribute.is_read_only and
          v8_types.wrapper_type(idl_type) and
          # There are some exceptions, however:
          not(
              # Node lifetime is managed by object grouping.
              v8_types.dom_node_type(idl_type) or
              # A self-reference is unnecessary.
              attribute.name == 'self' or
              # FIXME: Remove these hard-coded hacks.
              idl_type in ['EventHandler', 'Promise', 'Window'] or
              idl_type.startswith('HTML'))))