Issue with nested enums with gRPC

[trickleup]

Thanks for a great library. I've found an issue when working with nested enums and gRPC service definitions. It looks somewhat similar to #212, but doesn't seem the same, from what I can see.

better proto version: 2.0.0b4
protoc version: 3.19.4

This proto definition works:

syntax = "proto3";

package hello;

service GreetingAPI {
  rpc SayHello (Greeting)
    returns (Greeting) {}
}

// Greeting represents a message you can tell a user.
message Greeting {
  Foo foo = 1;
}

enum Foo {
  FOO_UNSPECIFIED = 0;
}

But when I nest the enum, like this:

syntax = "proto3";

package hello;

service GreetingAPI {
  rpc SayHello (Greeting)
    returns (Greeting) {}
}

// Greeting represents a message you can tell a user.
message Greeting {
  Foo foo = 1;
  enum Foo {
    FOO_UNSPECIFIED = 0;
  }
}

It fails with the following error:

Traceback (most recent call last):
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/bin/protoc-gen-python_betterproto", line 8, in <module>
    sys.exit(main())
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/lib/python3.9/site-packages/betterproto/plugin/main.py", line 32, in main
    response = generate_code(request)
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/lib/python3.9/site-packages/betterproto/plugin/parser.py", line 107, in generate_code
    read_protobuf_service(service, index, output_package)
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/lib/python3.9/site-packages/betterproto/plugin/parser.py", line 191, in read_protobuf_service
    ServiceMethodCompiler(
  File "<string>", line 7, in __init__
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/lib/python3.9/site-packages/betterproto/plugin/models.py", line 683, in __post_init__
    self.mutable_default_args  # ensure this is called before rendering
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/lib/python3.9/site-packages/betterproto/plugin/models.py", line 720, in mutable_default_args
    and f.default_value_string != "None"
  File "/Users/johan.genberg/projects/testing/betterproto/.venv/lib/python3.9/site-packages/betterproto/plugin/models.py", line 486, in default_value_string
    enum = next(
StopIteration
--python_betterproto_out: protoc-gen-python_betterproto: Plugin failed with status code 1.

I run betterproto like this:

protoc -I . --python_betterproto_out=lib test_fail.proto

The error seems to be due to some naming collision. Also, it only appears if the service definition is in the file. If I remove it, the nested enum works well.

I can work around this by not nesting the enum. But still wanted to report it, see if there was a more long term fix.

[Gobot1234]

This has already been fixed on the master branch there's unfortunately just no full release containing the fix

[trickleup]

Thanks for the response. Do you know when the next release will be out?

[Gobot1234]

Not sure the other collaborators seem to busy but it's pretty much ready to go it just needs someone to review #350 and #381