def test_oldPythonPy3(self):
"""
L{_checkPythonVersion} raises L{ImportError} when run on a version of
Python that is too old.
"""
sys.version_info = self.Py3unsupportedPythonVersion
with self.assertRaises(ImportError) as raised:
_checkPythonVersion()
self.assertEqual("Twisted on Python 3 requires Python %d.%d or later."
% self.Py3supportedPythonVersion,
str(raised.exception))
def test_newPythonPy3(self):
"""
L{_checkPythonVersion} returns L{None} when run on a version of Python
that is sufficiently new.
"""
sys.version_info = self.Py3supportedPythonVersion
self.assertIsNone(_checkPythonVersion())