bindings: Supports inheritance of [Unforgeable] attributes as accessor-type properties.

Source/bindings/scripts/interface_dependency_resolver.py

Index: Source/bindings/scripts/interface_dependency_resolver.py
diff --git a/Source/bindings/scripts/interface_dependency_resolver.py b/Source/bindings/scripts/interface_dependency_resolver.py
index 79b28ea133445b94448cf0229d84f171bfa38196..830bc148eb832c0418e053603459e075b51e7a6b 100644
--- a/Source/bindings/scripts/interface_dependency_resolver.py
+++ b/Source/bindings/scripts/interface_dependency_resolver.py
@@ -37,7 +37,7 @@ Design doc: http://www.chromium.org/developers/design-documents/idl-compiler#TOC
 """
 
 import os.path
-from utilities import idl_filename_to_component, is_valid_component_dependency
+from utilities import idl_filename_to_component, is_valid_component_dependency, merge_dict_recursively
 
 # The following extended attributes can be applied to a dependency interface,
 # and are then applied to the individual members when merging.
@@ -119,6 +119,8 @@ class InterfaceDependencyResolver(object):
             interface_info['dependencies_other_component_full_paths'],
             self.reader)
 
+        inherit_unforgeable_attributes(resolved_definitions, self.interfaces_info)
+
         for referenced_interface_name in interface_info['referenced_interfaces']:
             referenced_definitions = self.reader.read_idl_definitions(
                 self.interfaces_info[referenced_interface_name]['full_path'])
@@ -305,3 +307,42 @@ def transfer_extended_attributes(dependency_interface, dependency_interface_base
         update_attributes(constant.extended_attributes, merged_extended_attributes)
     for operation in dependency_interface.operations:
         update_attributes(operation.extended_attributes, merged_extended_attributes)
+
+
+def inherit_unforgeable_attributes(resolved_definitions, interfaces_info):
+    """Inherits [Unforgeable] attributes and updates the arguments accordingly.
+
+    For each interface in |resolved_definitions|, collects all [Unforgeable]
+    attributes in ancestor interfaces in the same component and adds them to
+    the interface.  'referenced_interfaces' and 'cpp_includes' in
+    |interfaces_info| are updated accordingly.
+    """
+    def collect_unforgeable_attributes_in_ancestors(interface_name, component):
+        if not interface_name:
+            # unforgeable_attributes, referenced_interfaces, cpp_includes
+            return [], [], set()
+        interface = interfaces_info[interface_name]
+        unforgeable_attributes, referenced_interfaces, cpp_includes = collect_unforgeable_attributes_in_ancestors(interface.get('parent'), component)
+        this_unforgeable = interface.get('unforgeable_attributes', {}).get(component, [])
+        unforgeable_attributes.extend(this_unforgeable)
+        this_referenced = [attr.idl_type.base_type for attr in this_unforgeable
+                           if attr.idl_type.base_type in
+                           interface.get('referenced_interfaces', [])]
+        referenced_interfaces.extend(this_referenced)
+        cpp_includes.update(interface.get('cpp_includes', {}).get(component, {}))
+        return unforgeable_attributes, referenced_interfaces, cpp_includes
+
+    for component, definitions in resolved_definitions.iteritems():
+        for interface_name, interface in definitions.interfaces.iteritems():
+            interface_info = interfaces_info[interface_name]
+            inherited_unforgeable_attributes, referenced_interfaces, cpp_includes = collect_unforgeable_attributes_in_ancestors(interface_info.get('parent'), component)
+            # This loop may process the same interface many times, so it's
+            # possible that we're adding the same attributes twice or more.
+            # So check if there is a duplicate.
+            for attr in inherited_unforgeable_attributes:
+                if attr not in interface.attributes:
+                    interface.attributes.append(attr)
+            referenced_interfaces.extend(interface_info.get('referenced_interfaces', []))
+            interface_info['referenced_interfaces'] = sorted(set(referenced_interfaces))

[tasak, 2015/07/29 12:56:45]

Just my perfornal preference. I would like to avoid updating interface_info
while resolving interface_dependency.

Is it possible to add a new extended attribute like
[PartialInterfaceImplementedAs]?
i.e. add UnforguableAttributeImplementedAs to attributes' extended attributes.
 

[Yuki, 2015/08/03 02:02:13]

Very good point.  It seems we may need redesign of IDL compiler, but it could be
a big work.  Let me leave this point as is and keep it in my mind, and when the
time come, let's work on the redesign.

+            merge_dict_recursively(interface_info,
+                                   {'cpp_includes': {component: cpp_includes}})