def test_delitem(self):
with self.assertRaises(KeyError):
del LruCache()['key']
pairs = [('a', 1), ('b', 2), ('c', 3), ('d', 4)]
cache = LruCache(pairs)
with self.assertRaises(KeyError):
del cache['key']
for index, (key, value) in enumerate(pairs):
del cache[key]
self.assertEqual(cache.items(), pairs[index+1:][::-1])
# start deleting from the tail
cache.update(pairs)
for index, (key, value) in enumerate(pairs[::-1]):
del cache[key]
index = len(pairs) - index - 1
self.assertEqual(cache.items(), pairs[:index][::-1])
def test_copy(self):
pairs = [('a', 1), ('b', 2), ('c', 3), ('d', 4)]
cache = LruCache(pairs)
self.assertEqual(cache.copy().items(), cache.items())
self.assertEqual(cache.copy().keys(), cache.keys())
self.assertEqual(LruCache().items(), LruCache().copy().items())
self.assertEqual(LruCache().keys(), LruCache().copy().keys())
def test_setitem(self):
with self.assertRaises(ValueError):
LruCache()['a'] = None
with self.assertRaises(ValueError):
LruCache()[None] = 'a'
with self.assertRaises(ValueError):
LruCache()[None] = None
cache = LruCache(capacity=10)
cache['a'] = 1
cache['b'] = 2
self.assertEqual(cache.items(), [('b', 2), ('a', 1)])
cache['a'] = 3
self.assertEqual(cache.items(), [('a', 3), ('b', 2)])
cache['b'] = 4
self.assertEqual(cache.items(), [('b', 4), ('a', 3)])
cache['c'] = 5
self.assertEqual(cache.items(), [('c', 5), ('b', 4), ('a', 3)])
del cache['c']
cache['c'] = 5
self.assertEqual(cache.items(), [('c', 5), ('b', 4), ('a', 3)])
def test_set_item(self):
"""Test putting item in cache."""
cache = LruCache(3)
cache['k1'] = 100
cache['k2'] = 200
cache['k3'] = 300
cache['k4'] = 400
self.assertEqual(len(cache), 3)
self.assertListEqual(list(cache.items()), [('k2', 200), ('k3', 300),
('k4', 400)])
def test_init(self):
with self.assertRaises(ValueError):
LruCache(capacity=0)
pairs = [('a', 1), ('b', 2), ('c', 3), ('d', 4)]
self.assertEqual(sorted(LruCache(pairs).items()), pairs)
self.assertEqual(sorted(LruCache(dict(pairs)).items()), pairs)
self.assertEqual(sorted(LruCache(**dict(pairs)).items()), pairs)
self.assertEqual(sorted(LruCache(pairs, e=4, f=5, r=6).items()),
pairs + [('e', 4), ('f', 5), ('r', 6)])
cache = LruCache(pairs)
cache.__init__([('e', 5), ('t', 6)])
self.assertEqual(sorted(cache.items()), pairs + [('e', 5), ('t', 6)])
def test_update_item(self):
"""Test update item in cache."""
cache = LruCache(3)
cache['k1'] = 100
cache['k2'] = 200
cache['k1'] = 300
self.assertEqual(len(cache), 2)
self.assertListEqual(list(cache.items()), [
('k2', 200),
('k1', 300),
])
