public async void Test_GivenAListOfUsers_WhenGetUsers_ThenResponseIsNotAltered() { var user1 = new CognitoUser("userId1", "clientId", cognitoPoolMock.Object, cognitoClientMock.Object); var user2 = new CognitoUser("userId2", "clientId", cognitoPoolMock.Object, cognitoClientMock.Object); var user3 = new CognitoUser("userId3", "clientId", cognitoPoolMock.Object, cognitoClientMock.Object); IEnumerable <CognitoUser> users = new List <CognitoUser>() { user1, user2, user3 }; userStoreMock.Setup(mock => mock.GetUsersAsync(null, null, "", It.IsAny <CancellationToken>())).Returns(Task.FromResult(users)).Verifiable(); var output = await userManager.GetUsersAsync().ConfigureAwait(false); Assert.Equal(users, output); userStoreMock.Verify(); }