diff options
Diffstat (limited to 'Lib/test/test_io.py')
| -rw-r--r-- | Lib/test/test_io.py | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py index bcf435f..a17fcee 100644 --- a/Lib/test/test_io.py +++ b/Lib/test/test_io.py @@ -2653,12 +2653,50 @@ class SignalsTest(unittest.TestCase): def test_interrupted_write_text(self): self.check_interrupted_write("xy", b"xy", mode="w", encoding="ascii") + def check_reentrant_write(self, data, **fdopen_kwargs): + def on_alarm(*args): + # Will be called reentrantly from the same thread + wio.write(data) + 1/0 + signal.signal(signal.SIGALRM, on_alarm) + r, w = os.pipe() + wio = self.io.open(w, **fdopen_kwargs) + try: + signal.alarm(1) + # Either the reentrant call to wio.write() fails with RuntimeError, + # or the signal handler raises ZeroDivisionError. + with self.assertRaises((ZeroDivisionError, RuntimeError)) as cm: + while 1: + for i in range(100): + wio.write(data) + wio.flush() + # Make sure the buffer doesn't fill up and block further writes + os.read(r, len(data) * 100) + exc = cm.exception + if isinstance(exc, RuntimeError): + self.assertTrue(str(exc).startswith("reentrant call"), str(exc)) + finally: + wio.close() + os.close(r) + + def test_reentrant_write_buffered(self): + self.check_reentrant_write(b"xy", mode="wb") + + def test_reentrant_write_text(self): + self.check_reentrant_write("xy", mode="w", encoding="ascii") + + class CSignalsTest(SignalsTest): io = io class PySignalsTest(SignalsTest): io = pyio + # Handling reentrancy issues would slow down _pyio even more, so the + # tests are disabled. + test_reentrant_write_buffered = None + test_reentrant_write_text = None + def test_main(): tests = (CIOTest, PyIOTest, |