When re-importing a submodule lazily after removing it, it's never added back to sys.modules.

[brittanyrey]

Bug report

Bug description:

While working on setting up testing infra for lazy_imports=all, I came across this test failure in test_trace. It appears that after importing a submodule, deleting said submodule, and then lazy importing it again--the module doesn't make it's way back into sys.modules.

Example failing code snippet:

import sys
modname = "test.test_lazy_import.data.pkg.bar"
import test.test_lazy_import.data.pkg.bar
del sys.modules[modname]
lazy import test.test_lazy_import.data.pkg.bar  # the issue is also seen when using lazy from
bar.f()
assert modname in sys.modules  # False

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-151408: Re-register submodules in sys.modules on lazy re-import #151411
• gh-151408: Fix bug with lazy importing a previously imported and removed module #151412

[bhuvi27]

I'm working on a fix for this.

[brittanyrey]

@bhuvi27 I have one already