iterators passed to writelines() can close their files; don't segfault #10125
diff --git a/Lib/test/test_file2k.py b/Lib/test/test_file2k.py
index fc8bfe9..ab09f21 100644
--- a/Lib/test/test_file2k.py
+++ b/Lib/test/test_file2k.py
@@ -135,6 +135,14 @@
def testReadWhenWriting(self):
self.assertRaises(IOError, self.f.read)
+ def testNastyWritelinesGenerator(self):
+ def nasty():
+ for i in range(5):
+ if i == 3:
+ self.f.close()
+ yield str(i)
+ self.assertRaises(ValueError, self.f.writelines, nasty())
+
def testIssue5677(self):
# Remark: Do not perform more than one test per open file,
# since that does NOT catch the readline error on Windows.