mypy not happy with .pyi rewriting

[aucampia]

This project is a great, thank you very much for making and maintaining it.

I have tried using it with typing however and I notice that mypy is not entirely happy with the rewriting of .pyi files.

I have setup an example here: https://github.com/aucampia/issue-20221116-python_protobuf_cloudevents/tree/a245d29c2b1600b6580c6db861b4b715e72b9b51

The specific .pyi file that upsets mypy is generated/protol/_plgen/example/v1/messages_pb2.pyi and the untransformed file is generated/proto/example/v1/messages_pb2.pyi

With the mypy config from the example, running mypy yields:

$ python -m poetry run mypy --show-error-codes --show-error-context 
tests/test_conflicting_ns.py:80: note: In module imported here:
generated/protol/_plgen/example/v1/messages_pb2.pyi: note: In member "field_b" of class "Something":
generated/protol/_plgen/example/v1/messages_pb2.pyi:24: error: Name "io.cloudevents.v1.cloudevents_pb2.CloudEvent" is not defined  [name-defined]
generated/protol/_plgen/example/v1/messages_pb2.pyi: note: In member "__init__" of class "Something":
generated/protol/_plgen/example/v1/messages_pb2.pyi:27: error: Name "io.cloudevents.v1.cloudevents_pb2.CloudEvent" is not defined  [name-defined]
Found 2 errors in 1 file (checked 5 source files)
make: *** [Makefile:78: python-validate-static] Error 1

The specific part of the transformation that is causing the problem is this I believe:

$ diff -u -r generated/proto/example/v1/messages_pb2.pyi generated/protol/_plgen/example/v1/messages_pb2.pyi 
--- generated/proto/example/v1/messages_pb2.pyi	2022-11-22 09:08:54.417836214 +0100
+++ generated/protol/_plgen/example/v1/messages_pb2.pyi	2022-11-22 09:08:55.062838530 +0100
@@ -5,32 +5,31 @@
 import builtins
 import google.protobuf.descriptor
 import google.protobuf.message
-import io.cloudevents.v1.cloudevents_pb2
+from ... import io
 import sys

If I change this by hand to instead do from ...io.cloudevents.v1 import cloudevents_pb2 as io_dot_cloudevents_dot_v1_dot_cloudevents__pb2 and make corresponding changes in the rest of the file to use io_dot_cloudevents_dot_v1_dot_cloudevents__pb2 instead of io.cloudevents.v1.cloudevents_pb2 then mypy is entirely happy.

[cpcloud]

@aucampia Can you paste the .proto file that reproduces this issue somewhere?

[aucampia]

All the proto files are in here: https://github.com/aucampia/issue-20221116-python_protobuf_cloudevents/tree/a245d29c2b1600b6580c6db861b4b715e72b9b51/spec/proto

but the file that the problems originate from is spec/proto/example/v1/messages.proto and its content is:

syntax = "proto3";

package example.v1;

import "io/cloudevents/v1/cloudevents.proto";

message Something {
  string field_a = 1;
  io.cloudevents.v1.CloudEvent field_b = 2;
}