https://github.com/python/cpython/commit/a327677905956ae0b239ff430a1346dfe26... commit: a327677905956ae0b239ff430a1346dfe265709e branch: master author: Carl Friedrich Bolz-Tereick <cfbolz@gmx.de> committer: GitHub <noreply@github.com> date: 2020-01-29T15:43:37Z summary: bpo-39485: fix corner-case in method-detection of mock (GH-18252) Replace check for whether something is a method in the mock module. The previous version fails on PyPy, because there no method wrappers exist (everything looks like a regular Python-defined function). Thus the isinstance(getattr(result, '__get__', None), MethodWrapperTypes) check returns True for any descriptor, not just methods. This condition could also return erroneously True in CPython for C-defined descriptors. Instead to decide whether something is a method, just check directly whether it's a function defined on the class. This passes all tests on CPython and fixes the bug on PyPy. files: A Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst M Lib/unittest/mock.py diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py index a3d8b6eab41a9..37ea5c7e45c8b 100644 --- a/Lib/unittest/mock.py +++ b/Lib/unittest/mock.py @@ -2748,7 +2748,7 @@ def _must_skip(spec, entry, is_type): continue if isinstance(result, (staticmethod, classmethod)): return False - elif isinstance(getattr(result, '__get__', None), MethodWrapperTypes): + elif isinstance(result, FunctionTypes): # Normal method => skip if looked up on type # (if looked up on instance, self is already skipped) return is_type @@ -2778,10 +2778,6 @@ def __init__(self, spec, spec_set=False, parent=None, type(ANY.__eq__), ) -MethodWrapperTypes = ( - type(ANY.__eq__.__get__), -) - file_spec = None diff --git a/Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst b/Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst new file mode 100644 index 0000000000000..f62c31fc686ad --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst @@ -0,0 +1,3 @@ +Fix a bug in :func:`unittest.mock.create_autospec` that would complain about +the wrong number of arguments for custom descriptors defined in an extension +module returning functions.