contrib/python-zstandard/tests/test_module_attributes.py

hook: add a 'hashook' function to test for hook existence

Preparing the data for some hooks can be expensive. Add a function to check if
a hook exists so we can skip useless preparation if no hook is configured.

from __future__ import unicode_literals

try:
    import unittest2 as unittest
except ImportError:
    import unittest

import zstd

from . common import (
    make_cffi,
)


@make_cffi
class TestModuleAttributes(unittest.TestCase):
    def test_version(self):
        self.assertEqual(zstd.ZSTD_VERSION, (1, 1, 3))

    def test_constants(self):
        self.assertEqual(zstd.MAX_COMPRESSION_LEVEL, 22)
        self.assertEqual(zstd.FRAME_HEADER, b'\x28\xb5\x2f\xfd')

    def test_hasattr(self):
        attrs = (
            'COMPRESSION_RECOMMENDED_INPUT_SIZE',
            'COMPRESSION_RECOMMENDED_OUTPUT_SIZE',
            'DECOMPRESSION_RECOMMENDED_INPUT_SIZE',
            'DECOMPRESSION_RECOMMENDED_OUTPUT_SIZE',
            'MAGIC_NUMBER',
            'WINDOWLOG_MIN',
            'WINDOWLOG_MAX',
            'CHAINLOG_MIN',
            'CHAINLOG_MAX',
            'HASHLOG_MIN',
            'HASHLOG_MAX',
            'HASHLOG3_MAX',
            'SEARCHLOG_MIN',
            'SEARCHLOG_MAX',
            'SEARCHLENGTH_MIN',
            'SEARCHLENGTH_MAX',
            'TARGETLENGTH_MIN',
            'TARGETLENGTH_MAX',
            'STRATEGY_FAST',
            'STRATEGY_DFAST',
            'STRATEGY_GREEDY',
            'STRATEGY_LAZY',
            'STRATEGY_LAZY2',
            'STRATEGY_BTLAZY2',
            'STRATEGY_BTOPT',
        )

        for a in attrs:
            self.assertTrue(hasattr(zstd, a), a)