Karthikeyan Singaravelan <[email protected]> added the comment:
It seems that TestCase in unittest.case accepts failureException attribute that
is raised on assertion failure. My initial approach is to subclass TestCase and
add a custom failure exception like MockException that is caught to add the
diff to the original message. I am adding @cjw296 and @mariocj89 for feedback
since I hope this can reuse unittest.case.TestCase implementation for diffs. I
think this is better done with a flag like verbose=True to display the
difference and defaulting to False since sometimes the message can be long
depending on args and kwargs. Also I find args (tuple) comparison to be little
distracting. Since this is an enhancement I am adding 3.8.
# Sample file
from unittest.mock import Mock
m = Mock()
m(1, 2, foo='bar', bar='baz')
m.assert_called_with(2, 3, bar='baz', foo='car')
# On 3.7
$ python3.7 /tmp/foo_4.py
Traceback (most recent call last):
File "/tmp/foo_4.py", line 5, in <module>
m.assert_called_with(2, 3, bar='baz', foo='car')
File
"/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/unittest/mock.py",
line 820, in assert_called_with
raise AssertionError(_error_message()) from cause
AssertionError: Expected call: mock(2, 3, bar='baz', foo='car')
# With patch
$ ./python.exe /tmp/foo_4.py
Traceback (most recent call last):
File "/tmp/foo_4.py", line 5, in <module>
m.assert_called_with(2, 3, bar='baz', foo='car')
File
"/Users/karthikeyansingaravelan/stuff/python/cpython/Lib/unittest/mock.py",
line 844, in assert_called_with
raise AssertionError(_error_message()) from cause
AssertionError: Expected call: mock(2, 3, bar='baz', foo='car')
Actual call: mock(1, 2, bar='baz', foo='bar')
args: Tuples differ: (2, 3) != (1, 2)
First differing element 0:
2
1
- (2, 3)
+ (1, 2)
kwargs: {'bar': 'baz', 'foo': 'car'} != {'foo': 'bar', 'bar': 'baz'}
- {'bar': 'baz', 'foo': 'car'}
? ^
+ {'bar': 'baz', 'foo': 'bar'}
? ^
----------
keywords: +patch
nosy: +cjw296, mariocj89
versions: +Python 3.8 -Python 2.7, Python 3.7
Added file: https://bugs.python.org/file47982/issue28054.diff
_______________________________________
Python tracker <[email protected]>
<https://bugs.python.org/issue28054>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
