Bump vendoring, move to proto3 release.

recipe_engine/third_party/google/protobuf/internal/python_message.py

 # Protocol Buffers - Google's data interchange format
 # Copyright 2008 Google Inc.  All rights reserved.
 # https://developers.google.com/protocol-buffers/
 #
 # 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.
@@ skipping 58 matching lines @@
 from google.protobuf.internal import containers
 from google.protobuf.internal import decoder
 from google.protobuf.internal import encoder
 from google.protobuf.internal import enum_type_wrapper
 from google.protobuf.internal import message_listener as message_listener_mod
 from google.protobuf.internal import type_checkers
 from google.protobuf.internal import well_known_types
 from google.protobuf.internal import wire_format
 from google.protobuf import descriptor as descriptor_mod
 from google.protobuf import message as message_mod
-from google.protobuf import symbol_database
 from google.protobuf import text_format
 
 _FieldDescriptor = descriptor_mod.FieldDescriptor
 _AnyFullTypeName = 'google.protobuf.Any'
 
 
 class GeneratedProtocolMessageType(type):
 
   """Metaclass for protocol message classes created at runtime from Descriptors.
 
   We add implementations for all methods described in the Message class.  We
   also create properties to allow getting/setting all fields in the protocol
   message.  Finally, we create slots to prevent users from accidentally
   "setting" nonexistent fields in the protocol message, which then wouldn't get
   serialized / deserialized properly.
 
   The protocol compiler currently uses this metaclass to create protocol
   message classes at runtime.  Clients can also manually create their own
   classes at runtime, as in this example:
 
   mydescriptor = Descriptor(.....)
-  class MyProtoClass(Message):
-    __metaclass__ = GeneratedProtocolMessageType
-    DESCRIPTOR = mydescriptor
+  factory = symbol_database.Default()
+  factory.pool.AddDescriptor(mydescriptor)
+  MyProtoClass = factory.GetPrototype(mydescriptor)
   myproto_instance = MyProtoClass()
   myproto.foo_field = 23
   ...
-
-  The above example will not work for nested types. If you wish to include them,
-  use reflection.MakeClass() instead of manually instantiating the class in
-  order to create the appropriate class structure.
   """
 
   # Must be consistent with the protocol-compiler code in
   # proto2/compiler/internal/generator.*.
   _DESCRIPTOR_KEY = 'DESCRIPTOR'
 
   def __new__(cls, name, bases, dictionary):
     """Custom allocation for runtime-generated class types.
 
     We override __new__ because this is apparently the only place
@@ skipping 798 matching lines @@
   This internal method is differnt from public Any Unpack method which takes
   the target message as argument. _InternalUnpackAny method does not have
   target message type and need to find the message type in descriptor pool.
 
   Args:
     msg: An Any message to be unpacked.
 
   Returns:
     The unpacked message.
   """
+  # TODO(amauryfa): Don't use the factory of generated messages.
+  # To make Any work with custom factories, use the message factory of the
+  # parent message.
+  # pylint: disable=g-import-not-at-top
+  from google.protobuf import symbol_database
+  factory = symbol_database.Default()
+
   type_url = msg.type_url
-  db = symbol_database.Default()
 
   if not type_url:
     return None
 
   # TODO(haberman): For now we just strip the hostname.  Better logic will be
   # required.
-  type_name = type_url.split("/")[-1]
-  descriptor = db.pool.FindMessageTypeByName(type_name)
+  type_name = type_url.split('/')[-1]
+  descriptor = factory.pool.FindMessageTypeByName(type_name)
 
   if descriptor is None:
     return None
 
-  message_class = db.GetPrototype(descriptor)
+  message_class = factory.GetPrototype(descriptor)
   message = message_class()
 
   message.ParseFromString(msg.value)
   return message
 
+
 def _AddEqualsMethod(message_descriptor, cls):
   """Helper for _AddMessageMethods()."""
   def __eq__(self, other):
     if (not isinstance(other, message_mod.Message) or
         other.DESCRIPTOR != self.DESCRIPTOR):
       return False
 
     if self is other:
       return True
 
@@ skipping 580 matching lines @@
   def _FindExtensionByNumber(self, number):
     """Tries to find a known extension with the field number.
 
     Args:
       number: Extension field number.
 
     Returns:
       Extension field descriptor.
     """
     return self._extended_message._extensions_by_number.get(number, None)