error: Name "Sequence" is not defined

[christianbundy]

Bug report

There's a discussion in gh-709 about a new bug, which seems to output nonsense error: Name "Sequence" is not defined errors. @ljodal has suggested that the regression was introduced in #991, and they've reproduced the issue in #1021 and https://github.com/ljodal/django-stubs-regression-test.

System information

• OS:
• python version: 3.10.x
• django version: 3.2.x
• mypy version: 0.962
• django-stubs version: 1.12.0
• django-stubs-ext version: 0.5.0

[christianbundy]

Here's a quick reproduction [ab]using a Docker to make this easy for anyone to test:

docker build -f - . << EOF
FROM python:3.10

RUN apt-get update && apt-get install git

RUN git clone https://github.com/ljodal/django-stubs.git

WORKDIR ./django-stubs

RUN git checkout 1ec8c44946c3de25cf88751dcd34c0ba58770ccf

RUN pip install -U pip setuptools wheel \
    && pip install -r ./requirements.txt

RUN pytest --mypy-ini-file=mypy.ini -k from_queryset_custom_auth_user_model
EOF

[flaeppe]

Just dropping by with some additional, related, discussion:

• Fix manager types scope #991 (comment) and downwards
• Set custom queryset methods as manager attrs instead of method copies #820 Resolved similar phantom errors, but for custom queryset methods (resolution for Custom manager causes phantom errors and sometimes crash #709 )

[ljodal]

I also suspect that #958 might be caused by the same underlaying bug, as it's similar in it appearance (something is wrong with types after copying). It happens whenever we use Model.objects.using() (but only when used directly on the manager I think, not on a query set) on models with a custom queryset

[flaeppe]

I also suspect that #958 might be caused by the same underlaying bug ...

Yep, I'd say you're right. Recognizing that _SpecialCase, from when anal_type has run.