如何为 discord 机器人编写单元测试

Question

I'm currently tried to write my first project with TDD and I've chosen a discord bot based on Discord.Net to do so.

But right off the start I face a problem regarding the abstract classes that Discord.Net uses. My first tests should concern the CommandHandler (which I will later extract into it's Interface and Implementation part).

The first test should check that the command is ignored if the bot is the author of the command. Therefore my OnMessageReceivedAsync -method will accept a SocketMessage , but this is an abstract class.

How should I go about this and write proper unit tests for an Discord.Net based discord bot?

UPDATE: I even tried it with Moq and mocking an IMessage , but I can't setup the mock because pretty much all of the fields are readonly. So I can't set the Author with this either.

My mock try is as follows:

using Discord;
using Moq;
using Xunit;

namespace Runa.DiscordBot.Infrastructure.Tests
{
    public class CommandHandlerTests
    {
        [Fact]
        public void OnMessageReceivedAsync_IgnoresSelfAsCommandIssuer()
        {
            Mock mockMessage = new Mock<IMessage>()
                .Setup(msg => msg.Author = "bot");
        }
    }
}

But as stated above with this I get the access-error when I try to set the msg.Author = "bot" , because the Author field has no set accessor.

Answer 1

Mock<IMessage> mockMessage = new Mock<IMessage>();

mockMessage.SetupGet(msg => msg.Author).Returns("bot");