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from pylru import *
import random
# This tests PyLRU by fuzzing it with random operations, then checking the
# results against another, simpler, LRU cache implementation.
class simplelrucache:
def __init__(self, size):
# Initialize the cache as empty.
self.cache = []
self.size = size
def __contains__(self, key):
for x in self.cache:
if x[0] == key:
return True
return False
def __getitem__(self, key):
for i in range(len(self.cache)):
x = self.cache[i]
if x[0] == key:
del self.cache[i]
self.cache.append(x)
return x[1]
raise KeyError
def __setitem__(self, key, value):
for i in range(len(self.cache)):
x = self.cache[i]
if x[0] == key:
x[1] = value
del self.cache[i]
self.cache.append(x)
return
if len(self.cache) == self.size:
self.cache = self.cache[1:]
self.cache.append([key, value])
def __delitem__(self, key):
for i in range(len(self.cache)):
if self.cache[i][0] == key:
del self.cache[i]
return
raise KeyError
def resize(self, x=None):
assert x > 0
self.size = x
if x < len(self.cache):
del self.cache[:len(self.cache) - x]
def test(a, b, c, d, verify):
for i in range(1000):
x = random.randint(0, 512)
y = random.randint(0, 512)
a[x] = y
b[x] = y
verify(c, d)
for i in range(1000):
x = random.randint(0, 512)
if x in a:
assert x in b
z = a[x]
z += b[x]
else:
assert x not in b
verify(c, d)
for i in range(256):
x = random.randint(0, 512)
if x in a:
assert x in b
del a[x]
del b[x]
else:
assert x not in b
verify(c, d)
def testcache():
def verify(a, b):
q = []
z = a.head
for j in range(len(a.table)):
q.append([z.key, z.value])
z = z.next
assert q == b.cache[::-1]
q2 = []
for x, y in q:
q2.append((x, y))
assert list(a.items()) == q2
assert list(zip(a.keys(), a.values())) == q2
assert list(a.keys()) == list(a)
a = lrucache(128)
b = simplelrucache(128)
verify(a, b)
test(a, b, a, b, verify)
a.size(71)
b.resize(71)
verify(a, b)
test(a, b, a, b, verify)
a.size(341)
b.resize(341)
verify(a, b)
test(a, b, a, b, verify)
a.size(127)
b.resize(127)
verify(a, b)
test(a, b, a, b, verify)
def wraptest():
def verify(p, x):
assert p == x.store
for key, value in x.cache.items():
assert x.store[key] == value
tmp = list(x.items())
tmp.sort()
tmp2 = list(p.items())
tmp2.sort()
assert tmp == tmp2
p = dict()
q = dict()
x = lruwrap(q, 128)
test(p, x, p, x, verify)
def wraptest2():
def verify(p, x):
for key, value in x.store.items():
if key not in x.dirty:
assert p[key] == value
for key in x.dirty:
assert x.cache.peek(key) == p[key]
for key, value in x.cache.items():
if key not in x.dirty:
assert x.store[key] == p[key] == value
tmp = list(x.items())
tmp.sort()
tmp2 = list(p.items())
tmp2.sort()
assert tmp == tmp2
p = dict()
q = dict()
x = lruwrap(q, 128, True)
test(p, x, p, x, verify)
x.sync()
assert p == q
def wraptest3():
def verify(p, x):
for key, value in x.store.items():
if key not in x.dirty:
assert p[key] == value
for key in x.dirty:
assert x.cache.peek(key) == p[key]
for key, value in x.cache.items():
if key not in x.dirty:
assert x.store[key] == p[key] == value
p = dict()
q = dict()
with lruwrap(q, 128, True) as x:
test(p, x, p, x, verify)
assert p == q
@lrudecorator(100)
def square(x):
return x*x
def testDecorator():
for i in range(1000):
x = random.randint(0, 200)
assert square(x) == x*x
if __name__ == '__main__':
random.seed()
for i in range(20):
testcache()
wraptest()
wraptest2()
wraptest3()
testDecorator()