Couldn't build proto file into descriptor pool [Python 3.13]

[cdce8p]

Encountered this issue while testing Python 3.13.0rc2. To reproduce

import proto

__protobuf__ = proto.module(
    package="some_module",
    manifest={"View", "Encoding"},
)

class View(proto.Enum):
    A = 0

class Encoding(proto.Enum):
    B = 0

$ python test.py
Traceback (most recent call last):
  File "/.../proto-plus-python/test.py", line 11, in <module>
    class Encoding(proto.Enum):
        B = 0
  File "/.../proto-plus-python/proto/enums.py", line 105, in __new__
    file_info.generate_file_pb(new_class=cls, fallback_salt=full_name)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/.../proto-plus-python/proto/_file_info.py", line 104, in generate_file_pb
    pool.Add(self.descriptor)
    ~~~~~~~~^^^^^^^^^^^^^^^^^
TypeError: Couldn't build proto file into descriptor pool: duplicate symbol 'some_module.__firstlineno__'

$ pip list
Package    Version
---------- -------
pip        24.2
proto-plus 1.24.0
protobuf   5.28.2

--
AFAICT the issue shows up as soon as two proto.Enum are defined in one module. A quick experiment suggests that the reason might be here

proto-plus-python/proto/enums.py

Lines 72 to 78 in e5e8533

	value=sorted(
	(
	descriptor_pb2.EnumValueDescriptorProto(name=name, number=number)
	# Minor hack to get all the enum variants out.
	for name, number in attrs.items()
	if isinstance(number, int)
	),

The attributes are only filtered by if isinstance(number, int). Python 3.13 added the new __firstlineno__ attribute which is an integer and as such not filtered as it should be. Just changing the condition here would be enough to resolve it, just not sure that's the best option as I'm unfamiliar with the code base.

-if isinstance(number, int)
+if isinstance(number, int) and name != "__firstlineno__"

[cdce8p]

@parthea Would you mind taking a look at this? It would be awesome to have support for Python 3.13 before the release next week. Especially since protobuf and grpcio are already compatible.

[cdce8p]

Some of the affected packages. There might be more

• google-cloud-texttospeech==2.17.2

import google.cloud.texttospeech

• google-cloud-speech==2.27.0

import google.cloud.speech_v1

• google-generativeai==0.8.3

import google.generativeai

• google-cloud-pubsub==2.26.0

import google.cloud.pubsub_v1