namespace package import error is order-dependent and not silenceable with ignore_missing_imports

[asottile-sentry]

Bug Report

my minimal reproduction unfortunately requires some third party dependencies but I've tried to make it as self-contained as possible:

To Reproduce

#!/usr/bin/env bash
set -euxo pipefail

rm -rf venv .mypy_cache

cat > pyproject.toml <<EOF
[[tool.mypy.overrides]]
module = ["google.*"]
ignore_missing_imports = true
EOF

cat > t.py <<EOF
from google.cloud import pubsub_v1
from google.cloud import bigtable
EOF

virtualenv -q venv
venv/bin/pip install -q google-cloud-bigtable==2.22.0 google-cloud-pubsub==2.19.0 mypy

venv/bin/mypy t.py

Expected Behavior

I expect it to produce no errors

Actual Behavior

$ bash t.sh 
+ rm -rf venv .mypy_cache
+ cat
+ cat
+ virtualenv -q venv
+ venv/bin/pip install -q google-cloud-bigtable==2.22.0 google-cloud-pubsub==2.19.0 mypy
+ venv/bin/mypy t.py
t.py:1: error: Module "google.cloud" has no attribute "pubsub_v1"  [attr-defined]
Found 1 error in 1 file (checked 1 source file)

what's even stranger is if the bigtable import is commented out it passes:

$ cat t.py 
from google.cloud import pubsub_v1
# from google.cloud import bigtable
$ rm -rf .mypy_cache/ && venv/bin/mypy t.py
Success: no issues found in 1 source file

I suspect something to do with namespace packages since google.* is a big bunch of them -- it also has various py.typed files which should have some things typed and others not -- google.cloud.pubsub_v1 does not have one of those (not to be confused with google.pubsub_v1 which does have one):

$ find venv/lib/python3.12/site-packages/google -name py.typed | sort
venv/lib/python3.12/site-packages/google/api_core/py.typed
venv/lib/python3.12/site-packages/google/cloud/_helpers/py.typed
venv/lib/python3.12/site-packages/google/cloud/_http/py.typed
venv/lib/python3.12/site-packages/google/cloud/_testing/py.typed
venv/lib/python3.12/site-packages/google/cloud/bigtable/py.typed
venv/lib/python3.12/site-packages/google/cloud/bigtable_admin/py.typed
venv/lib/python3.12/site-packages/google/cloud/bigtable_admin_v2/py.typed
venv/lib/python3.12/site-packages/google/cloud/bigtable_v2/py.typed
venv/lib/python3.12/site-packages/google/cloud/client/py.typed
venv/lib/python3.12/site-packages/google/cloud/environment_vars/py.typed
venv/lib/python3.12/site-packages/google/cloud/exceptions/py.typed
venv/lib/python3.12/site-packages/google/cloud/obsolete/py.typed
venv/lib/python3.12/site-packages/google/cloud/operation/py.typed
venv/lib/python3.12/site-packages/google/pubsub/py.typed
venv/lib/python3.12/site-packages/google/pubsub_v1/py.typed

I don't think the other directories have an effect as I deleted everything but the bigtable and pubsub_v1 directories and it still reproduces

Your Environment

• Mypy version used: 1.10.0
• Mypy command-line flags: see above
• Mypy configuration options from mypy.ini (and other config files): see above
• Python version used: 3.12.2 -- also reproduces on 3.11.x -- didn't try any others

[asottile-sentry]

deleting the bigtable py.typed file causes it to succeed as well, though I can't really do that (but it might hint at a solution?)

[asottile-sentry]

I believe this causes the bug -- or at least commenting it out "fixes" my problem --

mypy/mypy/modulefinder.py

Lines 543 to 549 in fb31409

	# Finally, we may be asked to produce an ancestor for an
	# installed package with a py.typed marker that is a
	# subpackage of a namespace package. We only fess up to these
	# if we would otherwise return "not found".
	ancestor = self.ns_ancestors.get(id)
	if ancestor is not None:
	return ancestor

[asottile-sentry]

appears to be a duplicate of #10360