Testing

TeleFlow handlers are normal C# classes, so most application behavior should be testable without Telegram.

What To Test

Test:

• application services separately from Telegram;
• handler routing assumptions through integration-style tests;
• state transitions;
• callback payload behavior;
• error handlers that change user-visible behavior;
• custom filters;
• custom storage implementations.

Do not test Telegram itself.

Keep Business Logic Out Of Handlers

Handlers should translate Telegram updates into application calls:

public sealed class TicketHandler
{
    private readonly TicketService _tickets;

    public TicketHandler(TicketService tickets)
    {
        _tickets = tickets;
    }

    [CommandTemplate("ticket {id:long}")]
    public async Task Handle(MessageContext ctx, long id, CancellationToken ct)
    {
        var ticket = await _tickets.GetAsync(id, ct);
        await ctx.Message.AnswerAsync(ticket.Title, ct);
    }
}

Then test TicketService with ordinary unit tests.

Use Direct Registration In Tests

Direct registration keeps narrow tests readable:

services.AddTelegramBot(options => options.Token = "test");
services.AddTelegramHandler<TicketHandler>();
services.AddMemoryStateStorage();

Generated registration is worth testing for application startup or package-level smoke tests.

Fake Telegram Client

For handler tests, replace ITelegramClient:

builder.Services.AddTelegramClient<FakeTelegramClient>();

Use a fake client to record outgoing Bot API calls and assert behavior.

State Tests

Stateful flows should be tested as sequences:

1. send /register;
2. send name;
3. send age;
4. assert state cleared;
5. assert expected messages or repository writes.

This catches routing, state, and data issues better than testing each handler in isolation.

Generated Path Tests

For production apps, add at least one startup test that uses:

services.AddTelegramHandlersFromAssembly(typeof(Program).Assembly);

That protects against accidentally removing IWF.TeleFlow.Generators or breaking generated metadata.