public async Task TestResponseReturnedCorrectlyAsync()
        {
            var expectedResponse = new Response(200, null);
            var mockSender       = new MockSender(expectedResponse);
            var sender           = new SigningSender(this.signer, mockSender);
            var result           = await sender.SendAsync(new Request());

            Assert.AreEqual(expectedResponse, result);
        }
        public async Task TestSigningOfRequestAsync()
        {
            var mockSender      = new MockSender(null);
            var urlPrefixSender = new URLPrefixSender("http://localhost/", mockSender);
            var sender          = new SigningSender(this.signer, urlPrefixSender);

            await sender.SendAsync(new Request());

            Assert.AreEqual(
                "http://localhost/?auth-id=id&auth-token=secret",
                mockSender.Request.GetUrl());
        }