handle_system_exit() flushs files to warranty the output order
PyObject_Print() writes into the C object stderr, whereas PySys_WriteStderr()
writes into the Python object sys.stderr. Each object has its own buffer, so
call sys.stderr.flush() and fflush(stderr).
diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index ecbc9db..2dd2746 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -86,6 +86,8 @@
# Python/pythonrun.c::PyErr_PrintEx() is tricky.
def test_exit(self):
+ import subprocess
+
self.assertRaises(TypeError, sys.exit, 42, 42)
# call without argument
@@ -140,20 +142,28 @@
self.fail("no exception")
# test that the exit machinery handles SystemExits properly
- import subprocess
rc = subprocess.call([sys.executable, "-c",
"raise SystemExit(47)"])
self.assertEqual(rc, 47)
+ def check_exit_message(code, expected):
+ process = subprocess.Popen([sys.executable, "-c", code],
+ stderr=subprocess.PIPE)
+ stdout, stderr = process.communicate()
+ self.assertEqual(process.returncode, 1)
+ self.assertTrue(stderr.startswith(expected), stderr)
+
+ # test that stderr buffer if flushed before the exit message is written
+ # into stderr
+ check_exit_message(
+ r'import sys; sys.stderr.write("unflushed,"); sys.exit("message")',
+ b"unflushed,message")
+
# test that the exit message is written with backslashreplace error
# handler to stderr
- import subprocess
- code = r'import sys; sys.exit("surrogates:\uDCFF")'
- process = subprocess.Popen([sys.executable, "-c", code],
- stderr=subprocess.PIPE)
- stdout, stderr = process.communicate()
- self.assertEqual(process.returncode, 1)
- self.assertTrue(stderr.startswith(b"surrogates:\\udcff"), stderr)
+ check_exit_message(
+ r'import sys; sys.exit("surrogates:\uDCFF")',
+ b"surrogates:\\udcff")
def test_getdefaultencoding(self):
self.assertRaises(TypeError, sys.getdefaultencoding, 42)