codekingpro/portable-devtools

1# Copyright 2019 Google LLC2#3# Licensed under the Apache License, Version 2.0 (the "License");4# you may not use this file except in compliance with the License.5# You may obtain a copy of the License at6#7#     https://www.apache.org/licenses/LICENSE-2.08#9# Unless required by applicable law or agreed to in writing, software10# distributed under the License is distributed on an "AS IS" BASIS,11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.12# See the License for the specific language governing permissions and13# limitations under the License.14 15import enum16 17from google.protobuf import descriptor_pb218 19from proto import _file_info20from proto import _package_info21from proto.marshal.rules.enums import EnumRule22 23 24class ProtoEnumMeta(enum.EnumMeta):25    """A metaclass for building and registering protobuf enums."""26 27    def __new__(mcls, name, bases, attrs):28        # Do not do any special behavior for `proto.Enum` itself.29        if bases[0] == enum.IntEnum:30            return super().__new__(mcls, name, bases, attrs)31 32        # Get the essential information about the proto package, and where33        # this component belongs within the file.34        package, marshal = _package_info.compile(name, attrs)35 36        # Determine the local path of this proto component within the file.37        local_path = tuple(attrs.get("__qualname__", name).split("."))38 39        # Sanity check: We get the wrong full name if a class is declared40        # inside a function local scope; correct this.41        if "<locals>" in local_path:42            ix = local_path.index("<locals>")43            local_path = local_path[: ix - 1] + local_path[ix + 1 :]44 45        # Determine the full name in protocol buffers.46        full_name = ".".join((package,) + local_path).lstrip(".")47        filename = _file_info._FileInfo.proto_file_name(48            attrs.get("__module__", name.lower())49        )50 51        # Retrieve any enum options.52        # We expect something that looks like an EnumOptions message,53        # either an actual instance or a dict-like representation.54        pb_options = "_pb_options"55        opts = attrs.pop(pb_options, {})56        # This is the only portable way to remove the _pb_options name57        # from the enum attrs.58        # In 3.7 onwards, we can define an _ignore_ attribute and do some59        # mucking around with that.60        if pb_options in attrs._member_names:61            if isinstance(attrs._member_names, list):62                idx = attrs._member_names.index(pb_options)63                attrs._member_names.pop(idx)64            else:  # Python 3.11.0b365                del attrs._member_names[pb_options]66 67        # Make the descriptor.68        enum_desc = descriptor_pb2.EnumDescriptorProto(69            name=name,70            # Note: the superclass ctor removes the variants, so get them now.71            # Note: proto3 requires that the first variant value be zero.72            value=sorted(73                (74                    descriptor_pb2.EnumValueDescriptorProto(name=name, number=number)75                    # Minor hack to get all the enum variants out.76                    for name, number in attrs.items()77                    if isinstance(number, int)78                ),79                key=lambda v: v.number,80            ),81            options=opts,82        )83 84        file_info = _file_info._FileInfo.maybe_add_descriptor(filename, package)85        if len(local_path) == 1:86            file_info.descriptor.enum_type.add().MergeFrom(enum_desc)87        else:88            file_info.nested_enum[local_path] = enum_desc89 90        # Run the superclass constructor.91        cls = super().__new__(mcls, name, bases, attrs)92 93        # We can't just add a "_meta" element to attrs because the Enum94        # machinery doesn't know what to do with a non-int value.95        # The pb is set later, in generate_file_pb96        cls._meta = _EnumInfo(full_name=full_name, pb=None)97 98        file_info.enums[full_name] = cls99 100        # Register the enum with the marshal.101        marshal.register(cls, EnumRule(cls))102 103        # Generate the descriptor for the file if it is ready.104        if file_info.ready(new_class=cls):105            file_info.generate_file_pb(new_class=cls, fallback_salt=full_name)106 107        # Done; return the class.108        return cls109 110 111class Enum(enum.IntEnum, metaclass=ProtoEnumMeta):112    """A enum object that also builds a protobuf enum descriptor."""113 114    def _comparable(self, other):115        # Avoid 'isinstance' to prevent other IntEnums from matching116        return type(other) in (type(self), int)117 118    def __hash__(self):119        return hash(self.value)120 121    def __eq__(self, other):122        if not self._comparable(other):123            return NotImplemented124 125        return self.value == int(other)126 127    def __ne__(self, other):128        if not self._comparable(other):129            return NotImplemented130 131        return self.value != int(other)132 133    def __lt__(self, other):134        if not self._comparable(other):135            return NotImplemented136 137        return self.value < int(other)138 139    def __le__(self, other):140        if not self._comparable(other):141            return NotImplemented142 143        return self.value <= int(other)144 145    def __ge__(self, other):146        if not self._comparable(other):147            return NotImplemented148 149        return self.value >= int(other)150 151    def __gt__(self, other):152        if not self._comparable(other):153            return NotImplemented154 155        return self.value > int(other)156 157 158class _EnumInfo:159    def __init__(self, *, full_name: str, pb):160        self.full_name = full_name161        self.pb = pb162