class SignalManagerTest(TestCase):
def setUp(self):
self.manager = SignalManager()
def _test_handler1(self):
pass
def _test_handler2(self):
pass
def test_push_pop(self):
"""
Make sure we can add and remove signal handlers, and that they get
updated appropriately.
"""
sig = signal.SIGHUP
saved = signal.getsignal(sig)
# push a new handler and make sure it gets installed
self.manager.push(sig, self._test_handler1)
self.assertEqual(signal.getsignal(sig), self._test_handler1)
# pop our handler and make sure the original value gets restored
handler = self.manager.pop(sig)
self.assertEqual(handler, self._test_handler1)
self.assertEqual(signal.getsignal(sig), saved)
def test_nested(self):
"""
Make sure nested calls to ``push`` and ``pop`` work as expected.
"""
sig = signal.SIGHUP
saved = signal.getsignal(sig)
# push a new handler and make sure it gets installed
self.manager.push(sig, self._test_handler1)
self.assertEqual(signal.getsignal(sig), self._test_handler1)
# push a second new handler and make sure it gets installed
self.manager.push(sig, self._test_handler2)
self.assertEqual(signal.getsignal(sig), self._test_handler2)
# pop our second handler and make sure the first one we installed gets set
handler = self.manager.pop(sig)
self.assertEqual(handler, self._test_handler2)
self.assertEqual(signal.getsignal(sig), self._test_handler1)
# pop our first handler and make sure the original value gets restoredet
handler = self.manager.pop(sig)
self.assertEqual(handler, self._test_handler1)
self.assertEqual(signal.getsignal(sig), saved)
def test_saved_first(self):
"""
Make sure ``pop`` raises a ``ValueError`` if ``push`` hasn't been called
first for a given signum.
"""
# fails if no handler saved
self.assertRaises(ValueError, self.manager.pop, 1)
# fails if handler saved but already popped
self.manager._saved_handlers = {1: []}
self.assertRaises(ValueError, self.manager.pop, 1)
# fails if other handlers exist, but not one for our signum
self.manager._saved_handlers = {2: [self._test_handler1]}
self.assertRaises(ValueError, self.manager.pop, 1)
def setUp(self):
self.manager = SignalManager()
