Inconsistency between used-before-assignment and possibly-used-before-assignment for if/elif/else

[nikita-leontiev]

Bug description

Below code leads to used-before-assignment error for func2:

from module import get_module_name

module_name = get_module_name()
if module_name == "module1":
    from module1 import func1
elif module_name == "module2":
    from module2 import func1, func2
elif module_name == "module3":
    from module3 import func1
else:
    assert False

if __name__ == "__main__":
    func1()
    func2()

Adding func2 import from module3:

from module import get_module_name

module_name = get_module_name()
if module_name == "module1":
    from module1 import func1
elif module_name == "module2":
    from module2 import func1, func2
elif module_name == "module3":
    from module3 import func1, func2
else:
    assert False

if __name__ == "__main__":
    func1()
    func2()

For some reason error changed to possibly-used-before-assignment.

Configuration

Without pylintrc.

Command used

pylint -sn --disable=E0401,C0114 test.py

Pylint output

$ pylint -sn --disable=E0401,C0114 test.py
************* Module test
test.py:15:4: E0601: Using variable 'func2' before assignment (used-before-assignment)
$ pylint -sn --disable=E0401,C0114 test.py
************* Module test
test.py:15:4: E0606: Possibly using variable 'func2' before assignment (possibly-used-before-assignment)

Expected behavior

E0601 error for both cases.

Pylint version

pylint 3.2.6
astroid 3.2.4
Python 3.8.10 (default, Jul 29 2024, 17:02:10)
[GCC 9.4.0]

OS / Environment

Ubuntu 20.04

Additional dependencies

No response

[jacobtylerwalls]

Thanks for the report. I think I would expect possibly-used-before-assignment in both cases. At a glance, the issue seems to be in NamesConsumer._uncertain_nodes_if_tests().