def test_hash_table_insertion_and_retrieval(self): ht = HashTable(8) hash_table_insert(ht, "key-0", "val-0") hash_table_insert(ht, "key-1", "val-1") hash_table_insert(ht, "key-2", "val-2") hash_table_insert(ht, "key-3", "val-3") hash_table_insert(ht, "key-4", "val-4") hash_table_insert(ht, "key-5", "val-5") hash_table_insert(ht, "key-6", "val-6") hash_table_insert(ht, "key-7", "val-7") hash_table_insert(ht, "key-8", "val-8") hash_table_insert(ht, "key-9", "val-9") return_value = hash_table_retrieve(ht, "key-0") self.assertTrue(return_value == "val-0") return_value = hash_table_retrieve(ht, "key-1") self.assertTrue(return_value == "val-1") return_value = hash_table_retrieve(ht, "key-2") self.assertTrue(return_value == "val-2") return_value = hash_table_retrieve(ht, "key-3") self.assertTrue(return_value == "val-3") return_value = hash_table_retrieve(ht, "key-4") self.assertTrue(return_value == "val-4") return_value = hash_table_retrieve(ht, "key-5") self.assertTrue(return_value == "val-5") return_value = hash_table_retrieve(ht, "key-6") self.assertTrue(return_value == "val-6") return_value = hash_table_retrieve(ht, "key-7") self.assertTrue(return_value == "val-7") return_value = hash_table_retrieve(ht, "key-8") self.assertTrue(return_value == "val-8") return_value = hash_table_retrieve(ht, "key-9") self.assertTrue(return_value == "val-9")
def test_auto_resizing(self):
ht = HashTable(1)
hash_table_insert(ht, 'first', 'test')
self.assertEqual(ht.capacity, 2)
hash_table_insert(ht, 'second', 'test2')
self.assertEqual(ht.capacity, 4)
hash_table_insert(ht, 'third', 'test3')
self.assertEqual(ht.capacity, 8)
hash_table_remove(ht, 'third')
hash_table_remove(ht, "second")
self.assertEqual(ht.capacity, 4)
def test_hash_table_removes_correctly(self):
ht = HashTable(8)
hash_table_insert(ht, "key-0", "val-0")
hash_table_insert(ht, "key-1", "val-1")
hash_table_insert(ht, "key-2", "val-2")
hash_table_insert(ht, "key-3", "val-3")
hash_table_insert(ht, "key-4", "val-4")
hash_table_insert(ht, "key-5", "val-5")
hash_table_insert(ht, "key-6", "val-6")
hash_table_insert(ht, "key-7", "val-7")
hash_table_insert(ht, "key-8", "val-8")
hash_table_insert(ht, "key-9", "val-9")
print(ht.storage)
hash_table_remove(ht, "key-9")
hash_table_remove(ht, "key-8")
hash_table_remove(ht, "key-7")
hash_table_remove(ht, "key-6")
hash_table_remove(ht, "key-5")
hash_table_remove(ht, "key-4")
hash_table_remove(ht, "key-3")
hash_table_remove(ht, "key-2")
hash_table_remove(ht, "key-1")
hash_table_remove(ht, "key-0")
return_value = hash_table_retrieve(ht, "key-0")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-1")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-2")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-3")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-4")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-5")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-6")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-7")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-8")
self.assertTrue(return_value is None)
return_value = hash_table_retrieve(ht, "key-9")
self.assertTrue(return_value is None)
def test_hash_table_resize(self):
ht = HashTable(8)
hash_table_insert(ht, "key-0", "val-0")
hash_table_insert(ht, "key-1", "val-1")
hash_table_insert(ht, "key-2", "val-2")
hash_table_insert(ht, "key-3", "val-3")
hash_table_insert(ht, "key-4", "val-4")
hash_table_insert(ht, "key-5", "val-5")
hash_table_insert(ht, "key-6", "val-6")
hash_table_insert(ht, "key-7", "val-7")
hash_table_insert(ht, "key-8", "val-8")
hash_table_insert(ht, "key-9", "val-9")
ht = hash_table_resize(ht)
self.assertTrue(len(ht.storage) == 16)
return_value = hash_table_retrieve(ht, "key-0")
self.assertTrue(return_value == "val-0")
return_value = hash_table_retrieve(ht, "key-1")
self.assertTrue(return_value == "val-1")
return_value = hash_table_retrieve(ht, "key-2")
self.assertTrue(return_value == "val-2")
return_value = hash_table_retrieve(ht, "key-3")
self.assertTrue(return_value == "val-3")
return_value = hash_table_retrieve(ht, "key-4")
self.assertTrue(return_value == "val-4")
return_value = hash_table_retrieve(ht, "key-5")
self.assertTrue(return_value == "val-5")
return_value = hash_table_retrieve(ht, "key-6")
self.assertTrue(return_value == "val-6")
return_value = hash_table_retrieve(ht, "key-7")
self.assertTrue(return_value == "val-7")
return_value = hash_table_retrieve(ht, "key-8")
self.assertTrue(return_value == "val-8")
return_value = hash_table_retrieve(ht, "key-9")
self.assertTrue(return_value == "val-9")
def test_doesnt_shrink_if_still_initial_size(self):
ht = HashTable(32)
hash_table_insert(ht, 'first', 'test')
self.assertEqual(ht.capacity, 32)
hash_table_remove(ht, 'first')
self.assertEqual(ht.capacity, 32)