def test_delete(self):
hash_table = MyHash()
# Test basic deletion
hash_table.set('hello', 'world')
length = len(hash_table.values())
hash_table.delete('hello')
self.assertLess(len(hash_table.values()), length)
def test_resize(self):
hash_table = MyHash()
# test both increasing in size when load factor is met
original_length = len(hash_table._buckets)
for i in range(30):
key = ''.join(random.choice(string.lowercase) for i in range(3))
val = ''.join(random.choice(string.lowercase) for i in range(3))
hash_table.set(key, val)
new_length = len(hash_table._buckets)
self.assertGreater(new_length, original_length)
# test decreasing in size when load is too small
for key in hash_table.keys()[:26]:
hash_table.delete(key)
new_length = len(hash_table._buckets)
self.assertEqual(new_length, original_length)
def test_keys_and_values(self):
hash_table = MyHash()
# random character generator for easy test insertion
def random_val():
return random.choice(string.lowercase)
[hash_table.set(random_val(), random_val()) for i in range(8)]
self.assertEqual(len(hash_table.values()), 8)
self.assertEqual(len(hash_table.keys()), 8)
def test_set_and_get(self):
hash_table = MyHash()
# test basic set and get functionality for strings
hash_table.set('hello', 'world')
self.assertEqual(hash_table.get('hello'), 'world')
# test basic set and get functionality for ints
hash_table.set(3, 5)
self.assertEqual(hash_table.get(3), 5)
# test basic set and get functionality for objects
class test(object):
pass
class test2(object):
pass
key = test()
val = test2()
hash_table.set(key, val)
self.assertIsInstance(hash_table.get(key), test2)
# test for invalid key
self.assertRaises(KeyError, hash_table.get, 'test')
