import unittest

from ttl_cache import TTLCache


class Clock:
    def __init__(self):
        self.now = 100.0

    def __call__(self):
        return self.now


class TTLCacheTests(unittest.TestCase):
    def setUp(self):
        self.clock = Clock()

    def test_round_trip(self):
        cache = TTLCache(2, 10, self.clock)
        cache.put("a", "A")
        self.assertEqual(cache.get("a"), "A")

    def test_expires_at_boundary(self):
        cache = TTLCache(2, 10, self.clock)
        cache.put("a", "A")
        self.clock.now += 10
        with self.assertRaises(KeyError):
            cache.get("a")

    def test_get_refreshes_lru(self):
        cache = TTLCache(2, 10, self.clock)
        cache.put("a", "A")
        cache.put("b", "B")
        cache.get("a")
        cache.put("c", "C")
        with self.assertRaises(KeyError):
            cache.get("b")


if __name__ == "__main__":
    unittest.main()