def test_deletion(self):
# Zero capacity cache is not allowed
with AssertRaises(ValueError):
c = LRUCache(0)
# Capacity = 1
c = LRUCache(1)
c[0] = '0'
c[1] = '1'
assert_eq(1, len(c))
assert_eq('1', c[1])
assert_is(miss, c.get(2))
del c[1]
assert_eq(0, len(c))
# Capacity = 2
c = LRUCache(2)
c[0] = '0'
c[1] = '1'
c[2] = '2'
del c[1]
assert_eq(1, len(c))
assert_is(miss, c.get(1))
assert_eq('2', c[2])
c = LRUCache(2)
c[0] = '0'
c[1] = '1'
c[2] = '2'
del c[2]
assert_eq(1, len(c))
assert_eq('1', c[1])
assert_is(miss, c.get(2))
# Capacity = 3
c = LRUCache(3)
c[0] = '0'
c[1] = '1'
c[2] = '2'
c[3] = '3'
del c[2]
assert_eq(2, len(c))
assert_is(miss, c.get(2))
assert_eq('1', c[1])
assert_eq('3', c[3])
# Deletion of invalid item
with AssertRaises(KeyError):
del c[15]
def test_get(self):
c = LRUCache(3)
c[0] = 'a'
c[1] = 'b'
c[2] = 'c'
# Getting a value should make it MRU
assert_in(1, c)
assert_eq('b', c.get(1))
self._check_order([(0, 'a'), (2, 'c'), (1, 'b')], c)
# Missing value should have no effect
assert_not_in(100, c)
assert_eq(miss, c.get(100))
self._check_order([(0, 'a'), (2, 'c'), (1, 'b')], c)
def test_get(self):
c = LRUCache(3)
c[0] = "a"
c[1] = "b"
c[2] = "c"
# Getting a value should make it MRU
assert_in(1, c)
assert_eq("b", c.get(1))
self._check_order([(0, "a"), (2, "c"), (1, "b")], c)
# Missing value should have no effect
assert_not_in(100, c)
assert_eq(miss, c.get(100))
self._check_order([(0, "a"), (2, "c"), (1, "b")], c)