diff --git a/Lib/test/pickletester.py b/Lib/test/pickletester.py --- a/Lib/test/pickletester.py +++ b/Lib/test/pickletester.py @@ -1416,6 +1416,26 @@ class AbstractPickleTests(unittest.TestC FRAME_SIZE_TARGET = 64 * 1024 + def check_frame_opcodes(self, pickled): + """ + Check the arguments of FRAME opcodes in a protocol 4+ pickle. + """ + frame_opcode_size = 9 + last_arg = last_offset = None + for op, arg, offset in pickletools.genops(pickled): + if op.name != 'FRAME': + continue + if last_offset is not None: + # The previous frame's size should be equal to the number + # of bytes up to the current frame. + frame_size = offset - last_offset - frame_opcode_size + self.assertEqual(frame_size, last_arg) + last_arg, last_offset = arg, offset + # The last frame's size should be equal to the number of bytes up + # to the pickle's end. + frame_size = len(pickled) - last_offset - frame_opcode_size + self.assertEqual(frame_size, last_arg) + def test_framing_many_objects(self): obj = list(range(10**5)) for proto in range(4, pickle.HIGHEST_PROTOCOL + 1): @@ -1429,6 +1449,7 @@ class AbstractPickleTests(unittest.TestC self.FRAME_SIZE_TARGET / 2) self.assertLessEqual(bytes_per_frame, self.FRAME_SIZE_TARGET * 1) + self.check_frame_opcodes(pickled) def test_framing_large_objects(self): N = 1024 * 1024 @@ -1440,6 +1461,7 @@ class AbstractPickleTests(unittest.TestC self.assertEqual(obj, unpickled) n_frames = count_opcode(pickle.FRAME, pickled) self.assertGreaterEqual(n_frames, len(obj)) + self.check_frame_opcodes(pickled) def test_optional_frames(self): if pickle.HIGHEST_PROTOCOL < 4: