public void AddOrGet_string()
        {
            //Arrange
            var store = new Store(new IStorage[] { new DisabledStorageHelperClass() }, cache: new DisabledCacheHelperClass());
            StoreResult <string> presistedValue = store.EnsurePresistAsync("StringsAreImmutable").GetAwaiter().GetResult();
            var target = new StoreResultCache();

            //Act
            var result = target.AddOrGet(presistedValue);

            //Assert
            Assert.AreSame(presistedValue, result);
        }
        public void AddOrGet_null()
        {
            //Arrange
            var target = new StoreResultCache();

            //Act
            try
            {
                target.AddOrGet <string>(null);
            }
            catch (ArgumentNullException)
            {
                return;
            }

            //Assert
            Assert.Fail();
        }