After renaming the first test_errors method to test_errors_1 and the
second one to test_errors_2:

$ /bin/sh -c "cd Lib/ctypes/test; ../../../python runtests.py test_functions.py"
....F................
======================================================================
FAIL: test_errors_1 (ctypes.test.test_functions.FunctionTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "./Lib/ctypes/test/test_functions.py", line 227, in test_errors_1
    self.assertRaises(TypeError, f, X()) #cannot convert parameter
AssertionError: TypeError not raised by _testfunc_p_p

----------------------------------------------------------------------
Ran 21 tests in 0.007s

FAILED (failures=1)

@Xavier can you provide a patch for this issue?

This issue has been entered while checking for duplicate test names in issue 16079.

Still fails on Python 3.8.0a3+.

en, in python 3.8.0a3, I got those other error info:

$ /home/shihai/workspace/cpython/python test_functions.py

ERROR:root:code for hash md5 was not found.
Traceback (most recent call last):
  File "/home/shihai/workspace/cpython/Lib/hashlib.py", line 244, in <module>
    globals()[__func_name] = __get_hash(__func_name)
  File "/home/shihai/workspace/cpython/Lib/hashlib.py", line 113, in __get_builtin_constructor
    raise ValueError('unsupported hash type ' + name)
ValueError: unsupported hash type md5

but in master branch, the test case is ok.

There are two tests with same name in the same test class  (ctypes.test.test_functions test_errors)
After merging both and re-run I encounter with this error
which looks like it was always there but overwritten by other test (with same name)

....F...........s.s...
======================================================================
FAIL: test_errors (__main__.FunctionTestCase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/furkan/cpython/Lib/ctypes/test/test_functions.py", line 219, in test_errors
    self.assertRaises(TypeError, f, X()) #cannot convert parameter
AssertionError: TypeError not raised by _testfunc_p_p

----------------------------------------------------------------------
Ran 22 tests in 0.003s

New changeset a5610057615779ca6fc75d9e006d2fae644a94d3 by andrei kulakov in branch 'main':
bpo-19113: Remove unused test_errors from ctypes tests (GH-28008)
https://github.com/python/cpython/commit/a5610057615779ca6fc75d9e006d2fae644a94d3

Change made in Python 3.11: duplicate test removed. Closing.