class LRUCache(object):
def __init__(self):
self.hash_table = HashTable(50, hash_djb2)
self.time_tracker = []
self.size = 0
def get(self, key, func):
result = self.hash_table.get(key)
if result == 'No item found at key ' + key:
if self.size == 50:
key_to_remove = self.time_tracker[49]
self.hash_table.remove(key_to_remove)
del (self.time_tracker[-1])
self.size = self.size - 1
value = func(key)
result = self.hash_table.put(key, value)
self.time_tracker.insert(0, key)
self.size = self.size + 1
return result
def test_put_overrides_key_value_pair():
hash_function = hash_djb2
hash_table = HashTable(10, hash_function)
hash_table.put('banana', 'strawberry')
hash_table.put('banana', 'blueberry')
expected_kvp = {'banana': 'blueberry'}
assert hash_table.data[1][0] == expected_kvp
def test_remove_deletes_value_at_key():
hash_function = hash_djb2
hash_table = HashTable(10, hash_function)
hash_table.put('banana', 'strawberry')
expected_kvp = {'banana': 'strawberry'}
assert hash_table.data[1][0] == expected_kvp
hash_table.remove('banana')
assert len(hash_table.data[1]) == 0
def test_put_adds_multiple_key_value_pairs():
hash_function = hash_djb2
hash_table = HashTable(10, hash_function)
hash_table.put('banana', 'strawberry')
expected_kvp = {'banana': 'strawberry'}
assert hash_table.data[1][0] == expected_kvp
hash_table.put('blueberry', 'apple')
expected_kvp = {'blueberry': 'apple'}
assert hash_table.data[3][0] == expected_kvp
def __init__(self):
self.hash_table = HashTable(50, hash_djb2)
self.time_tracker = []
self.size = 0
def test_remove_returns_no_item_message_with_no_item():
hash_function = hash_djb2
hash_table = HashTable(10, hash_function)
result = hash_table.remove('StarWars')
assert result == 'No item found at key StarWars'
def test_get_returns_value():
hash_function = hash_djb2
hash_table = HashTable(10, hash_function)
hash_table.put('banana', 'strawberry')
result = hash_table.get('banana')
assert result == 'strawberry'
def test_hash_table_can_be_created_with_proper_parameters():
hash_function = hash_djb2
result = HashTable(10, hash_function)
assert result.data == [[], [], [], [], [], [], [], [], [], []]
assert result.size == 10
assert result.max_size == 110