Karthikeyan Singaravelan <[email protected]> added the comment:
If I understand the issue correctly it's as below is a simple reproducer where
target is resolved with {'a': 1} during the construction of the decorator [0]
though it's redefined later in the program as target = dict(a=2). Also here due
to this since target is reassigned the decorator just stores a reference to
{'a': 1} and updates it with {'b': 2} leaving the reference to dict object
{'a': 2} unpatched in test_with_decorator. Meanwhile in case of the context
manager (test_with_context_manager) it's created and resolved at the time it's
executed hence updating the object {'a': 2} correctly. A possible fix would be
to store the reference to the string path of the patch '__main__.target' and
try it again with importer function. I will take a further look into this. It
would be helpful if you can confirm this reproducer is good enough and
resembles the original report.
from unittest import mock
target = dict(a=1)
@mock.patch.dict('__main__.target', dict(b=2))
def test_with_decorator():
print(f"target inside decorator : {target}")
def test_with_context_manager():
with mock.patch.dict('__main__.target', dict(b=2)):
print(f"target inside context : {target}")
target = dict(a=2)
test_with_decorator()
test_with_context_manager()
$ python3 test_foo.py
target inside decorator : {'a': 2}
target inside context : {'a': 2, 'b': 2}
[0]
https://github.com/python/cpython/blob/3208880f1c72800bacf94a2045fcb0436702c7a1/Lib/unittest/mock.py#L1624
----------
nosy: +xtreak
type: -> behavior
versions: +Python 3.8
_______________________________________
Python tracker <[email protected]>
<https://bugs.python.org/issue35512>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
