Error When Appending Enum to Repeated Field

[BenRKarl]

This issue appears to be a side effect of the bug fixes released in 1.14.2 as it isn't an issue in previous versions.

For context, all the Enums in our API are structured like this, i.e. an outer message and inner enum.

For a simple repro case, in a enum_test.py file paste this:

import proto

class BarEnum(proto.Message):
    class Bar(proto.Enum):
        BAR = 0
        BAZ = 1

class Foo(proto.Message):
    bars = proto.RepeatedField(
        proto.ENUM,
        number=1,
        enum=BarEnum.Bar
    )

Then from a repl:

>>> from enum_test import Foo, BarEnum
>>> foo = Foo()
>>> bar = BarEnum.Bar.BAR
>>> foo.bars.append(bar)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "~/.pyenv/versions/3.7.0/lib/python3.7/_collections_abc.py", line 971, in append
    self.insert(len(self), value)
  File "~/lib/python3.7/site-packages/proto/marshal/collections/repeated.py", line 178, in insert
    pb_value = self._marshal.to_proto(self._pb_type, value, strict=True)
  File "~/lib/python3.7/site-packages/proto/marshal/marshal.py", line 215, in to_proto
    expected=proto_type.__name__, got=pb_value.__class__.__name__,
TypeError: Parameter must be instance of the same class; expected Bar, got int

[software-dov]

Able to reproduce, working on a fix.

[software-dov]

Turns out the nested enum isn't necessary to reproduce.