Add assertFloatsAreIdentical/assertComplexAreIdentical to unittest (or kwarg to assertEqual)?

[skirpichev]

Feature or enhancement

Proposal:

Clones of assertFloatsAreIdentical() are scattered across the CPython tests: https://github.com/python/cpython/blob/d8f82432a36178a2376cc2d0984b02bb03f6d55f/Lib/test/test_complex.py#L74 https://github.com/python/cpython/blob/d8f82432a36178a2376cc2d0984b02bb03f6d55f/Lib/test/test_cmath.py#L68 https://github.com/python/cpython/blob/d8f82432a36178a2376cc2d0984b02bb03f6d55f/Lib/test/test_float.py#L1069 https://github.com/python/cpython/blob/d8f82432a36178a2376cc2d0984b02bb03f6d55f/Lib/test/test_capi/test_getargs.py#L440

Maybe it's worth to have a dedicated check?

Or a special kwarg for the assertEqual method, to workaround NAN and -0.0 values for floats/complexes.

Edit:

Or at least some support from Lib/test/support... I was adding similar helper yet in another test file and that looks odd.

Numpy has numpy.testing.assert_equal():

>>> np.testing.assert_equal([0.0], [+0.0])
>>> np.testing.assert_equal([0.0], [-0.0])
Traceback (most recent call last):
  ...
AssertionError: 
Items are not equal:
item=0

 ACTUAL: 0.0
 DESIRED: -0.0
>>> np.testing.assert_equal([np.nan], [np.nan])
>>> np.testing.assert_equal([0.0], [np.nan])
Traceback (most recent call last):
  ...
AssertionError: 
Items are not equal:
item=0

 ACTUAL: 0.0
 DESIRED: nan

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Linked PRs

• gh-121071
• gh-123840
• gh-123841

[skirpichev]

pr is ready: https://github.com/python/cpython/pull/121071 (it implements the last option: methods added to test.support)