The warning in (Loose)Version is emitted before __repr__ works

[Miro Hrončok]

This is possibly a cosmetic issue. When (Loose)Version emits a warning, the object is not yet fully constructed and __repr__ fails.

Consider this test:

from distutils.version import LooseVersion

def test_loose_version():
    LooseVersion("1")

And run it with pytest test_foo.py -W error::DeprecationWarning. When distutils is from here and not form the standard library (e.g. when I have setuptools 60+ installed), the error looks like this:

============================= test session starts ==============================
platform linux -- Python 3.10.2, pytest-7.0.1, pluggy-1.0.0
rootdir: .../tmp/wtf
collected 1 item

test_foo.py F                                                            [100%]

=================================== FAILURES ===================================
______________________________ test_loose_version ______________________________

    def test_loose_version():
>       LooseVersion("1")

test_foo.py:4: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <[AttributeError("'LooseVersion' object has no attribute 'vstring'") raised in repr()] LooseVersion object at 0x7f9fa98f6080>
vstring = '1'

    def __init__ (self, vstring=None):
>       warnings.warn(
            "distutils Version classes are deprecated. "
            "Use packaging.version instead.",
            DeprecationWarning,
            stacklevel=2,
        )
E       DeprecationWarning: distutils Version classes are deprecated. Use packaging.version instead.

__venv__/lib64/python3.10/site-packages/setuptools/_distutils/version.py:53: DeprecationWarning
=========================== short test summary info ============================
FAILED test_foo.py::test_loose_version - DeprecationWarning: distutils Versio...
============================== 1 failed in 0.08s ===============================

The problematic bit is:

self = <[AttributeError("'LooseVersion' object has no attribute 'vstring'") raised in repr()] LooseVersion object at 0x7f9fa98f6080>

Would it make sense to move the deprecation warning after vstring is set?

[Miro Hrončok]

Thanks