def test_quality_default(self):
        ht = HashTable(buckets=1024)
        """
        Uses the default structure
        """
        self.assertEqual(ht.quality(), 0)

        for i in range(512):
            ht.increment(str(i), 1 + (i % 13))

        self.assertAlmostEqual(ht.quality(), 2.0 / 3)

        for i in range(1024):
            ht.increment(str(1024 + i), 1 + (i % 17))

        self.assertAlmostEqual(ht.quality(), 2.0, delta=0.015)
Esempio n. 2
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class HashTablePickleTest(unittest.TestCase):
    """
    Functional tests for determining size (cardinality) of hashtable and iterations.
    """

    def setUp(self):
        self.ht = HashTable(buckets=64)

    def tearDown(self):
        if os.path.isfile(filename):
            os.remove(filename)

    def check_hashtable(self, reloaded):
        self.assertEqual(len(reloaded), len(self.ht))
        self.assertEqual(reloaded.buckets(), self.ht.buckets())
        self.assertEqual(reloaded.total(), self.ht.total())
        self.assertEqual(set(reloaded.items()), set(self.ht.items()))
        self.assertEqual(reloaded.quality(), self.ht.quality())
        self.assertEqual(reloaded.cardinality(), self.ht.cardinality())

    def store_and_load(self):
        with open(filename, 'wb') as outfile:
            pickle.dump(self.ht, outfile)

        with open(filename, 'rb') as outfile:
            reloaded = pickle.load(outfile)

        return reloaded

    def test_pickle_empty(self):
        reloaded = self.store_and_load()
        self.check_hashtable(reloaded)

    def test_pickle_simple(self):
        self.ht.update("boss")
        self.ht.update("pickling")

        reloaded = self.store_and_load()
        self.check_hashtable(reloaded)

    def test_pickle_deleted(self):
        self.ht.update("boss")
        self.ht.update("pickling")
        del self.ht['g']
        del self.ht['s']

        reloaded = self.store_and_load()
        self.check_hashtable(reloaded)

    def test_pickle_pruned(self):
        for i in range(120):
            self.ht.increment(str(i), 1 + ((i * 27) % 17))

        reloaded = self.store_and_load()
        self.check_hashtable(reloaded)

    def test_pickle_large(self):
        self.ht = HashTable(buckets=2 ** 25)
        self.ht.update("boss")
        self.ht.update("pickling")
        self.ht.update("verylargetable")

        reloaded = self.store_and_load()
        self.check_hashtable(reloaded)