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Co-authored-by: Serhiy Storchaka <[email protected]>

Author: skirpichev

Lib/test/test_long.py

@@ -1374,16 +1374,15 @@ def equivalent_python(n, length, byteorder, signed=False):
         check(tests4, 'little', signed=False)
 
         self.assertRaises(OverflowError, (256).to_bytes, 1, 'big', signed=False)
-        self.assertRaises(OverflowError, (256).to_bytes, 1, 'big', signed=True)
         self.assertRaises(OverflowError, (256).to_bytes, 1, 'little', signed=False)
-        self.assertRaises(OverflowError, (256).to_bytes, 1, 'little', signed=True)
         self.assertRaises(OverflowError, (128).to_bytes, 1, 'big', signed=True)
         self.assertRaises(OverflowError, (128).to_bytes, 1, 'little', signed=True)
         self.assertRaises(OverflowError, (-129).to_bytes, 1, 'big', signed=True)
         self.assertRaises(OverflowError, (-129).to_bytes, 1, 'little', signed=True)
         self.assertRaises(OverflowError, (-1).to_bytes, 2, 'big', signed=False)
         self.assertRaises(OverflowError, (-1).to_bytes, 2, 'little', signed=False)
         self.assertEqual((0).to_bytes(0, 'big'), b'')
+        self.assertEqual((0).to_bytes(0, 'big'), b'', signed=True)
         self.assertEqual((1).to_bytes(5, 'big'), b'\x00\x00\x00\x00\x01')
         self.assertEqual((0).to_bytes(5, 'big'), b'\x00\x00\x00\x00\x00')
         self.assertEqual((-1).to_bytes(5, 'big', signed=True),