Message11166

On Windows 10 I observe this or rather similar output frequently in test_io, test_io_jy and test_univnewlines:

Traceback (most recent call last):
  File "Lib\test\test_io.py", line 2504, in test_read_nonbytes
    t = self.TextIOWrapper(NonbytesStream('a'))
  File "D:\workspace\linux\Jython\ssh\jython\dist\Lib\_io.py", line 1037, in __init__
    raise ValueError("invalid encoding: %r" % encoding)
ValueError: invalid encoding: None

It always names one of these locations:

_io.py line 1037
_pyio.py line 1489