closes bpo-28557: error message for bad raw readinto (GH-7496)
Co-authored-by: Benjamin Peterson <benjamin@python.org>
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 7b8511b..c0d67a17 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -1587,6 +1587,22 @@
with self.assertRaisesRegex(TypeError, "BufferedReader"):
self.tp(io.BytesIO(), 1024, 1024, 1024)
+ def test_bad_readinto_value(self):
+ rawio = io.BufferedReader(io.BytesIO(b"12"))
+ rawio.readinto = lambda buf: -1
+ bufio = self.tp(rawio)
+ with self.assertRaises(OSError) as cm:
+ bufio.readline()
+ self.assertIsNone(cm.exception.__cause__)
+
+ def test_bad_readinto_type(self):
+ rawio = io.BufferedReader(io.BytesIO(b"12"))
+ rawio.readinto = lambda buf: b''
+ bufio = self.tp(rawio)
+ with self.assertRaises(OSError) as cm:
+ bufio.readline()
+ self.assertIsInstance(cm.exception.__cause__, TypeError)
+
class PyBufferedReaderTest(BufferedReaderTest):
tp = pyio.BufferedReader