Added tests for not blocking lock timeout

tests/test_backend.py

@@ -677,15 +677,27 @@ def test_expire_at(self, cache: RedisCache):
 
     def test_lock(self, cache: RedisCache):
         lock = cache.lock("foobar")
-        lock.acquire(blocking=True)
+        assert lock.acquire(blocking=True)
+
+        assert cache.has_key("foobar")
+        lock.release()
+        assert not cache.has_key("foobar")
+
+    def test_lock_not_blocking(self, cache: RedisCache):
+        lock = cache.lock("foobar")
+        assert lock.acquire(blocking=False)
+
+        lock2 = cache.lock("foobar")
+
+        assert not lock2.acquire(blocking=False)
 
         assert cache.has_key("foobar")
         lock.release()
         assert not cache.has_key("foobar")
 
     def test_lock_released_by_thread(self, cache: RedisCache):
         lock = cache.lock("foobar", thread_local=False)
-        lock.acquire(blocking=True)
+        assert lock.acquire(blocking=True)
 
         def release_lock(lock_):
             lock_.release()