Added StringStackTraceFactory

[jamescrosswell]

Resolves #3439

• Stack Trace missing for NativeAOT App #3439

Description and Usage

This PR introduces a new stack trace factory that SDK users can enable explicitly for AOT compiled applications only if they're not getting useful stack traces from the default SentryStackTraceFactory.

It can be enabled via the SentryOptions when initialising Sentry:

SentrySdk.UseSentry(options => {
    // ...All the usual setup
    options.UseStackTraceFactory(new StringStackTraceFactory(options));
});

If this proves useful enough, we can simplify how that gets wired up.

Initial testing

I tested this out with the sample code from the related issue and the resulting stack trace is worse than what you get from the SentryStackTraceFactory.

For folks who aren't getting any stack trace at all, this might be an improvement... although I'm unable to reproduce a scenario where I don't have any stack trace.

Examples

SentryStackTraceFactory

SimpleStackTraceFactory

[bruno-garcia]

Is this regex coming from another file in the repo or it's a new regex? curious how tested/vetted this is

[jamescrosswell]

It's a new regex and the short answer is "not very"... which is one reason this is marked as Experimental.

We do have these unit tests but I'm not sure what this string is likely to look like in all the different real world scenarios.

This one (the fallback) is the regex that @filipnavara is using here:

sentry-dotnet/src/Sentry/Extensibility/StringStackTraceFactory.cs

Line 26 in 45b3258

private const string StackTraceLinePattern = @"at (.+)\.(.+) \+";

I'm hoping that between the two of those we can extract something sensible.

[filipnavara]

We have been using this regex in production since October 2024. It may not be fool-proof but it's somewhat battle-tested.

[bruno-garcia]

Is it on by default on AOT then?

How do I turn it on?

Would be nice to have a mention of that in the changelog too.

[Flash0ver]

Perhaps something we could also document in Troubleshooting when released?

[jamescrosswell]

Yeah when @Flash0ver and I discussed we were thinking we wouldn't promote this too widely, since it's quite experimental. However there are some additional docs on SentryOptions.UseStackTraceFactory (which is how you'd add this):

sentry-dotnet/src/Sentry/SentryOptions.cs

Lines 1637 to 1643 in e4120a9

	/// <para>
	/// By default, Sentry uses the <see cref="SentryStackTraceFactory"/> to create stack traces and this implementation
	/// offers the most comprehensive functionality. However, full stack traces are not available in AOT compiled
	/// applications. If you are compiling your applications AOT and the stack traces that you see in Sentry are not
	/// informative enough, you could consider using the StringStackTraceFactory instead. This is not as functional but
	/// is guaranteed to provide at least _something_ useful in AOT compiled applications.
	/// </para>

And we figured we'd add something to our troubleshooting docs as well...

I'll add a blurb in the description of this PR as well.

[bruno-garcia]

Some notes on changelog otherwise lgtm