Method test_odd_flush

Lib/test/test_zlib.py:629–648

(self)

    @unittest.skipUnless(hasattr(zlib, 'Z_SYNC_FLUSH'),
                         'requires zlib.Z_SYNC_FLUSH')
    def test_odd_flush(self):
        # Test for odd flushing bugs noted in 2.0, and hopefully fixed in 2.1
        import random
        # Testing on 17K of "random" data

        # Create compressor and decompressor objects
        co = zlib.compressobj(zlib.Z_BEST_COMPRESSION)
        dco = zlib.decompressobj()

        # Try 17K of data
        # generate random data stream
        data = random.randbytes(17 * 1024)

        # compress, sync-flush, and decompress
        first = co.compress(data)
        second = co.flush(zlib.Z_SYNC_FLUSH)
        expanded = dco.decompress(first + second)

        # if decompressed data is different from the input data, choke.
        self.assertEqual(expanded, data, "17K random source doesn't match")

    def test_empty_flush(self):
        # Test that calling .flush() on unused objects works.