recreate_module: set __spec__ to the new module

[skshetry]

The recreated module has __spec__ set to None, due to which find_spec throws ValueError.

Reading PEP-451 and Python's docs for __spec__, it seems that __spec__ can be None in some cases but generally it should be set.

Here's the issue that this tries to fix:

>>> from importlib.util import find_spec
>>> find_spec("celery")
ModuleSpec(name='celery', loader=<_frozen_importlib_external.SourceFileLoader object at 0x7fadf901ea10>, origin='/home/user/projects/iterative/celery/celery/__init__.py', submodule_search_locations=['/home/user/projects/iterative/celery/celery'])
>>> import celery
>>> find_spec("celery")
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
Input In [4], in <cell line: 0>()
----> 1 find_spec("celery")

File <frozen importlib.util>:114, in find_spec(name, package)

ValueError: celery.__spec__ is None

I noticed this when investigating failure in pylint/astroid, see PyCQA/pylint#7488 and PyCQA/astroid#1802.

[codecov]

Codecov Report

Base: 89.75% // Head: 89.60% // Decreases project coverage by -0.14% ⚠️

Coverage data is based on head (d36cb9b) compared to base (34533ab).
Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7773      +/-   ##
==========================================
- Coverage   89.75%   89.60%   -0.15%     
==========================================
  Files         138      128      -10     
  Lines       17007    15860    -1147     
  Branches     2515     2346     -169     
==========================================
- Hits        15264    14212    -1052     
+ Misses       1491     1421      -70     
+ Partials      252      227      -25     

Flag	Coverage Δ
unittests	89.59% <100.00%> (-0.15%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
celery/local.py	92.13% <100.00%> (+0.02%)	⬆️
celery/bin/celery.py
celery/result.py
celery/concurrency/__init__.py
celery/events/__init__.py
celery/security/__init__.py
celery/beat.py
celery/worker/__init__.py
celery/app/__init__.py
celery/__init__.py
... and 1 more

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[skshetry]

The test failure looks unrelated.

[auvipy]

yes, can add some tests for the changes proposed?

[skshetry]

I can add something like follows, but I am not sure if it's worth it considering it's only used once:

from importlib.util import find_spec

class test_celery_import:
    def test_import_celery(self, monkeypatch):
        import celery

        monkeypatch.delitem(sys.modules, "celery", raising=False)
        spec = find_spec("celery")
        assert spec

        assert celery.__spec__ == spec
        assert find_spec("celery") == spec

[auvipy]

some test is better the no test, so lets add the test as well

[skshetry]

Thanks, I have added one.