public void SetOverrides_SetsCookie()
        {
            var response = Substitute.For <HttpResponseBase>();
            var cookies  = new HttpCookieCollection();

            response.Cookies.Returns(cookies);
            _context.Response.Returns(response);

            _provider.SetOverrides(_validOverrides);

            cookies.Should().HaveCount(1);
            var cookie = cookies[CookieOverrideProvider.CookieName];

            cookie.Should().NotBeNull();
            var overrides = cookie.Value.Decrypt().Deserialize <Dictionary <string, bool> >();

            ValidateOverrides(overrides);
        }