Add stack trace to remote protocol ExceptionDetails

[codecat]

Is your feature request related to a problem? Please describe.

We currently don't get any stack trace in the Avalonia designer, meaning that problems are extremely hard to track down. For example, when the designer shows "Invalid markup" (see screenshot):

And the Avalonia Diagnostics output shows this:

23:00:59.004 [Information] 34320 Connection initialized
23:00:59.773 [Error] 34320 UpdateXamlResult error
System.Xaml.XamlException: Value cannot be null. (Parameter 'control')

It's practically impossible to know what really happened here without a stack trace.

Describe the solution you'd like

If we serialize the stack trace, we can display it in places where it matters.

I believe this commit should do the trick: codecat@607f31f

Then, we can make a change in AvaloniaVS to display the stack trace:

https://github.com/AvaloniaUI/AvaloniaVS/blob/3c210142a90d4a99f682c4df30ad8f6f03baca6f/AvaloniaVS.Shared/Services/PreviewerProcess.cs#L465

(I'm unsure how/if this would display in the Error List tab in AvaloniaVS, but that's probably an issue for that specific repository 😅)

As per contribution guidelines, I am opening an issue first, but I can have a PR ready to go. I assume it also needs some tests?

Describe alternatives you've considered

No response

Additional context

No response

[codecat]

Following up on this. Do you want a PR with the proposed solution?

[kekekeks]

Avalonia/src/Avalonia.DesignerSupport/Remote/RemoteDesignerEntryPoint.cs

Lines 243 to 247 in db10780

	s_transport.Send(new UpdateXamlResultMessage
	{
	Error = e.ToString(),
	Exception = new ExceptionDetails(e),
	});

seems to include the full exception details in Error field.

[kekekeks]

ExceptionDetails object was supposed to be there to indicate a particular line number and line position, not to swallow all the info.

[codecat]

I see, I must've missed that! In that case, the required change would just be in AvaloniaVS, here:

https://github.com/AvaloniaUI/AvaloniaVS/blob/3c210142a90d4a99f682c4df30ad8f6f03baca6f/AvaloniaVS.Shared/Services/PreviewerProcess.cs#L452-L468

update.Error is only used if update.Exception is null. Okay - I will make a PR there. 😊

[timunie]

Thx for your contribution @codecat 👍. This is indeed a very useful info.