class TestCache:
def __init__(self):
self.cache = Cache(SIZE)
def test_read_write(self):
# basic write and read
self.cache.write("test_key", "test_value")
assert "test_value" == self.cache.beginRead("test_key")
# beginRead: read key not present
try:
self.cache.beginRead("key_not_present")
assert False
except:
assert True
# endRead: read key not present
try:
self.cache.endRead("key_not_present")
assert False
except:
assert True
def test_eviction(self):
""" To check an entry is never evicted once beginRead is called """
self.cache.write("test_key", "test_value")
value = self.cache.beginRead("test_key")
for i in range(TEST_SIZE):
self.cache.write(i, i)
try:
# if evicted, endRead should throw and exception
self.cache.endRead("test_key")
assert True
except:
assert False
def test_size(self):
""" size of hash_db should never exceed specified size of cache """
# size
for i in range(TEST_SIZE):
self.cache.write(i, i)
assert len(self.cache.hash_db) <= SIZE
