def test_hash_table():
ht = HashTable()
print('hash table: {}'.format(ht))
print('\nTesting set:')
for key, value in [('I', 1), ('V', 5), ('X', 10)]:
print('set({!r}, {!r})'.format(key, value))
ht.set(key, value)
print('hash table: {}'.format(ht))
print('\nTesting get:')
for key in ['I', 'V', 'X']:
value = ht.get(key)
print('get({!r}): {!r}'.format(key, value))
print('contains({!r}): {}'.format('X', ht.contains('X')))
print('length: {}'.format(ht.length()))
# Enable this after implementing delete method
delete_implemented = False
if delete_implemented:
print('\nTesting delete:')
for key in ['I', 'V', 'X']:
print('delete({!r})'.format(key))
ht.delete(key)
print('hash table: {}'.format(ht))
print('contains(X): {}'.format(ht.contains('X')))
print('length: {}'.format(ht.length()))
def test_contains(self):
ht = HashTable()
ht.set('I', 1)
ht.set('V', 5)
ht.set('X', 10)
assert ht.contains('I') is True
assert ht.contains('V') is True
assert ht.contains('X') is True
assert ht.contains('A') is False
def test_set_and_get(self):
ht = HashTable()
ht.set('I', 1)
ht.set('V', 5)
ht.set('X', 10)
assert ht.get('I') == 1
assert ht.get('V') == 5
assert ht.get('X') == 10
assert ht.length() == 3
with self.assertRaises(KeyError):
ht.get('A') # Key does not exist
def test_delete(self):
ht = HashTable()
ht.set('I', 1)
ht.set('V', 5)
ht.set('X', 10)
assert ht.length() == 3
ht.delete('I')
ht.delete('X')
assert ht.length() == 1
with self.assertRaises(KeyError):
ht.delete('X') # Key no longer exists
with self.assertRaises(KeyError):
ht.delete('A') # Key does not exist
def test_set_twice_and_get(self):
ht = HashTable()
ht.set('I', 1)
ht.set('V', 4)
ht.set('X', 9)
assert ht.length() == 3
ht.set('V', 5) # Update value
ht.set('X', 10) # Update value
assert ht.get('I') == 1
assert ht.get('V') == 5
assert ht.get('X') == 10
assert ht.length() == 3 # Check length is not overcounting
def test_length(self):
ht = HashTable()
assert ht.length() == 0
ht.set('I', 1)
assert ht.length() == 1
ht.set('V', 5)
assert ht.length() == 2
ht.set('X', 10)
assert ht.length() == 3
def test_items(self):
ht = HashTable()
assert ht.items() == []
ht.set('I', 1)
assert ht.items() == [('I', 1)]
ht.set('V', 5)
self.assertCountEqual(ht.items(), [('I', 1), ('V', 5)])
ht.set('X', 10)
self.assertCountEqual(ht.items(), [('I', 1), ('V', 5), ('X', 10)])
def test_values(self):
ht = HashTable()
assert ht.values() == []
ht.set('I', 1)
assert ht.values() == [1]
ht.set('V', 5)
self.assertCountEqual(ht.values(), [1, 5]) # Ignore item order
ht.set('X', 10)
self.assertCountEqual(ht.values(), [1, 5, 10]) # Ignore item order
def test_keys(self):
ht = HashTable()
assert ht.keys() == []
ht.set('I', 1)
assert ht.keys() == ['I']
ht.set('V', 5)
self.assertCountEqual(ht.keys(), ['I', 'V']) # Ignore item order
ht.set('X', 10)
self.assertCountEqual(ht.keys(), ['I', 'V', 'X']) # Ignore item order