Invalid code generated when package name contains uppercase letter

[paskozdilar]

Summary

Title

Reproduction Steps

This protofile works:

// proto/test.proto
syntax = "proto3";

package p;

service Service {
  rpc Method(Empty) returns (Empty) {}
}

message Empty {}

This doesn't:

// proto/test.proto
syntax = "proto3";

package P;

service Service {
  rpc Method(Empty) returns (Empty) {}
}

message Empty {}

With the latter, betterproto compiles to this:

# Generated by the protocol buffer compiler.  DO NOT EDIT!
# sources: test.proto
# plugin: python-betterproto
# This file has been @generated

from dataclasses import dataclass
from typing import (
    TYPE_CHECKING,
    Dict,
    Optional,
)

import betterproto
import grpclib
from betterproto.grpc.grpclib_server import ServiceBase

from .. import PEmpty as _PEmpty__

# [...]

The from .. import PEmpty is invalid import as nothing exists in the parent package.

Command used:

python3 -m grpc_tools.protoc --proto_path=./proto/ --python_betterproto_out=./proto/ proto/*.proto

Python environment (output of pip freeze):

betterproto @ git+https://github.com/danielgtaylor/python-betterproto@5666393f9d10e13609d8eeac8d1ab3815dce5fd6
black==24.2.0
click==8.1.7
grpcio==1.62.1
grpcio-tools==1.62.1
grpclib==0.4.7
h2==4.1.0
hpack==4.0.0
hyperframe==6.0.1
isort==5.13.2
Jinja2==3.1.3
MarkupSafe==2.1.5
multidict==6.0.5
mypy-extensions==1.0.0
nodeenv==1.8.0
packaging==24.0
pathspec==0.12.1
platformdirs==4.2.0
protobuf==4.25.3
pyright==1.1.353
python-dateutil==2.9.0.post0
six==1.16.0
typing_extensions==4.10.0

Expected Results

Correct code generated

Actual Results

Incorrect code generated

System Information

libprotoc 3.12.4
Python 3.11.0rc1
Name: betterproto
Version: 2.0.0b6
Summary: A better Protobuf / gRPC generator & library
Home-page: https://github.com/danielgtaylor/python-betterproto
Author: Daniel G. Taylor
Author-email: [email protected]
License: MIT
Location:
Requires: grpclib, python-dateutil, typing-extensions
Required-by:

Checklist

• I have searched the issues for duplicates.
• I have shown the entire traceback, if possible.
• I have verified this issue occurs on the latest prelease of betterproto which can be installed using pip install -U --pre betterproto, if possible.

[gbmhunter]

I have got the same issue. I'm running the generation on Linux with betterproto v2.0.0b6. Adding any uppercase letter to any part of the package name in the .proto causes the same import error, where there are imports that don't exist in the parent __init__.py. Problem goes away if I use all lowercase letters.

[vkorotkovs]

The problem lies in the regex expression for splitting the source type into a tuple:

python-betterproto/src/betterproto/compile/importing.py

Lines 29 to 42 in 1f88b67

	def parse_source_type_name(field_type_name: str) -> Tuple[str, str]:
	"""
	Split full source type name into package and type name.
	E.g. 'root.package.Message' -> ('root.package', 'Message')
	'root.Message.SomeEnum' -> ('root', 'Message.SomeEnum')
	"""
	package_match = re.match(r"^\.?([^A-Z]+)\.(.+)", field_type_name)
	if package_match:
	package = package_match.group(1)
	name = package_match.group(2)
	else:
	package = ""
	name = field_type_name.lstrip(".")
	return package, name

However, your package naming should probably follow the style guide, which suggests using all lowercase letters. Adhering to this guideline would prevent this issue from occurring in the first place.

[hf-kklein]

See #437