cpython/Lib/unittest/test/test_break.py

307 lines
11 KiB
Python

import gc
import io
import os
import sys
import signal
import weakref
import unittest
from test import support
@unittest.skipUnless(hasattr(os, 'kill'), "Test requires os.kill")
@unittest.skipIf(sys.platform =="win32", "Test cannot run on Windows")
class TestBreak(unittest.TestCase):
int_handler = None
# This number was smart-guessed, previously tests were failing
# after 7th run. So, we take `x * 2 + 1` to be sure.
default_repeats = 15
def setUp(self):
self._default_handler = signal.getsignal(signal.SIGINT)
if self.int_handler is not None:
signal.signal(signal.SIGINT, self.int_handler)
def tearDown(self):
signal.signal(signal.SIGINT, self._default_handler)
unittest.signals._results = weakref.WeakKeyDictionary()
unittest.signals._interrupt_handler = None
def withRepeats(self, test_function, repeats=None):
if not support.check_impl_detail(cpython=True):
# Override repeats count on non-cpython to execute only once.
# Because this test only makes sense to be repeated on CPython.
repeats = 1
elif repeats is None:
repeats = self.default_repeats
for repeat in range(repeats):
with self.subTest(repeat=repeat):
# We don't run `setUp` for the very first repeat
# and we don't run `tearDown` for the very last one,
# because they are handled by the test class itself.
if repeat != 0:
self.setUp()
try:
test_function()
finally:
if repeat != repeats - 1:
self.tearDown()
def testInstallHandler(self):
default_handler = signal.getsignal(signal.SIGINT)
unittest.installHandler()
self.assertNotEqual(signal.getsignal(signal.SIGINT), default_handler)
try:
pid = os.getpid()
os.kill(pid, signal.SIGINT)
except KeyboardInterrupt:
self.fail("KeyboardInterrupt not handled")
self.assertTrue(unittest.signals._interrupt_handler.called)
def testRegisterResult(self):
result = unittest.TestResult()
self.assertNotIn(result, unittest.signals._results)
unittest.registerResult(result)
try:
self.assertIn(result, unittest.signals._results)
finally:
unittest.removeResult(result)
def testInterruptCaught(self):
def test(result):
pid = os.getpid()
os.kill(pid, signal.SIGINT)
result.breakCaught = True
self.assertTrue(result.shouldStop)
def test_function():
result = unittest.TestResult()
unittest.installHandler()
unittest.registerResult(result)
self.assertNotEqual(
signal.getsignal(signal.SIGINT),
self._default_handler,
)
try:
test(result)
except KeyboardInterrupt:
self.fail("KeyboardInterrupt not handled")
self.assertTrue(result.breakCaught)
self.withRepeats(test_function)
def testSecondInterrupt(self):
# Can't use skipIf decorator because the signal handler may have
# been changed after defining this method.
if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
self.skipTest("test requires SIGINT to not be ignored")
def test(result):
pid = os.getpid()
os.kill(pid, signal.SIGINT)
result.breakCaught = True
self.assertTrue(result.shouldStop)
os.kill(pid, signal.SIGINT)
self.fail("Second KeyboardInterrupt not raised")
def test_function():
result = unittest.TestResult()
unittest.installHandler()
unittest.registerResult(result)
with self.assertRaises(KeyboardInterrupt):
test(result)
self.assertTrue(result.breakCaught)
self.withRepeats(test_function)
def testTwoResults(self):
def test_function():
unittest.installHandler()
result = unittest.TestResult()
unittest.registerResult(result)
new_handler = signal.getsignal(signal.SIGINT)
result2 = unittest.TestResult()
unittest.registerResult(result2)
self.assertEqual(signal.getsignal(signal.SIGINT), new_handler)
result3 = unittest.TestResult()
try:
os.kill(os.getpid(), signal.SIGINT)
except KeyboardInterrupt:
self.fail("KeyboardInterrupt not handled")
self.assertTrue(result.shouldStop)
self.assertTrue(result2.shouldStop)
self.assertFalse(result3.shouldStop)
self.withRepeats(test_function)
def testHandlerReplacedButCalled(self):
# Can't use skipIf decorator because the signal handler may have
# been changed after defining this method.
if signal.getsignal(signal.SIGINT) == signal.SIG_IGN:
self.skipTest("test requires SIGINT to not be ignored")
def test_function():
# If our handler has been replaced (is no longer installed) but is
# called by the *new* handler, then it isn't safe to delay the
# SIGINT and we should immediately delegate to the default handler
unittest.installHandler()
handler = signal.getsignal(signal.SIGINT)
def new_handler(frame, signum):
handler(frame, signum)
signal.signal(signal.SIGINT, new_handler)
try:
os.kill(os.getpid(), signal.SIGINT)
except KeyboardInterrupt:
pass
else:
self.fail("replaced but delegated handler doesn't raise interrupt")
self.withRepeats(test_function)
def testRunner(self):
# Creating a TextTestRunner with the appropriate argument should
# register the TextTestResult it creates
runner = unittest.TextTestRunner(stream=io.StringIO())
result = runner.run(unittest.TestSuite())
self.assertIn(result, unittest.signals._results)
def testWeakReferences(self):
# Calling registerResult on a result should not keep it alive
result = unittest.TestResult()
unittest.registerResult(result)
ref = weakref.ref(result)
del result
# For non-reference counting implementations
gc.collect();gc.collect()
self.assertIsNone(ref())
def testRemoveResult(self):
result = unittest.TestResult()
unittest.registerResult(result)
unittest.installHandler()
self.assertTrue(unittest.removeResult(result))
# Should this raise an error instead?
self.assertFalse(unittest.removeResult(unittest.TestResult()))
try:
pid = os.getpid()
os.kill(pid, signal.SIGINT)
except KeyboardInterrupt:
pass
self.assertFalse(result.shouldStop)
def testMainInstallsHandler(self):
failfast = object()
test = object()
verbosity = object()
result = object()
default_handler = signal.getsignal(signal.SIGINT)
class FakeRunner(object):
initArgs = []
runArgs = []
def __init__(self, *args, **kwargs):
self.initArgs.append((args, kwargs))
def run(self, test):
self.runArgs.append(test)
return result
class Program(unittest.TestProgram):
def __init__(self, catchbreak):
self.exit = False
self.verbosity = verbosity
self.failfast = failfast
self.catchbreak = catchbreak
self.tb_locals = False
self.testRunner = FakeRunner
self.test = test
self.result = None
p = Program(False)
p.runTests()
self.assertEqual(FakeRunner.initArgs, [((), {'buffer': None,
'verbosity': verbosity,
'failfast': failfast,
'tb_locals': False,
'warnings': None})])
self.assertEqual(FakeRunner.runArgs, [test])
self.assertEqual(p.result, result)
self.assertEqual(signal.getsignal(signal.SIGINT), default_handler)
FakeRunner.initArgs = []
FakeRunner.runArgs = []
p = Program(True)
p.runTests()
self.assertEqual(FakeRunner.initArgs, [((), {'buffer': None,
'verbosity': verbosity,
'failfast': failfast,
'tb_locals': False,
'warnings': None})])
self.assertEqual(FakeRunner.runArgs, [test])
self.assertEqual(p.result, result)
self.assertNotEqual(signal.getsignal(signal.SIGINT), default_handler)
def testRemoveHandler(self):
default_handler = signal.getsignal(signal.SIGINT)
unittest.installHandler()
unittest.removeHandler()
self.assertEqual(signal.getsignal(signal.SIGINT), default_handler)
# check that calling removeHandler multiple times has no ill-effect
unittest.removeHandler()
self.assertEqual(signal.getsignal(signal.SIGINT), default_handler)
def testRemoveHandlerAsDecorator(self):
default_handler = signal.getsignal(signal.SIGINT)
unittest.installHandler()
@unittest.removeHandler
def test():
self.assertEqual(signal.getsignal(signal.SIGINT), default_handler)
test()
self.assertNotEqual(signal.getsignal(signal.SIGINT), default_handler)
@unittest.skipUnless(hasattr(os, 'kill'), "Test requires os.kill")
@unittest.skipIf(sys.platform =="win32", "Test cannot run on Windows")
class TestBreakDefaultIntHandler(TestBreak):
int_handler = signal.default_int_handler
@unittest.skipUnless(hasattr(os, 'kill'), "Test requires os.kill")
@unittest.skipIf(sys.platform =="win32", "Test cannot run on Windows")
class TestBreakSignalIgnored(TestBreak):
int_handler = signal.SIG_IGN
@unittest.skipUnless(hasattr(os, 'kill'), "Test requires os.kill")
@unittest.skipIf(sys.platform =="win32", "Test cannot run on Windows")
class TestBreakSignalDefault(TestBreak):
int_handler = signal.SIG_DFL
if __name__ == "__main__":
unittest.main()