test_zlib.py 文件源码

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
        try:
            # In 2.3 and later, WichmannHill is the RNG of the bug report
            gen = random.WichmannHill()
        except AttributeError:
            try:
                # 2.2 called it Random
                gen = random.Random()
            except AttributeError:
                # others might simply have a single RNG
                gen = random
        gen.seed(1)
        data = genblock(1, 17 * 1024, generator=gen)

        # 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")