def test_discards_oldest_value_on_overflow():
lru = SimpleLRUCache(2)
assert lru.put("a", True) == False
assert lru.put("b", True) == False
assert lru.put("c", True) == False
assert lru.get("a") is None
assert lru.get("b") == True
assert lru.get("c") == True
def test_value_becomes_new_on_replace():
lru = SimpleLRUCache(2)
assert lru.put("a", True) == False
assert lru.put("b", True) == False
assert lru.put("a", True) == True # b is now oldest
assert lru.put("c", True) == False # b is discarded as oldest
assert lru.get("a") is True
assert lru.get("b") is None
assert lru.get("c") is True