Preserve original stacktrace in state machines if available

[vzarytovskii]

Description

Preserve original stacktrace in resumable state machines generated code, if avalable.

Before:

at Microsoft.FSharp.Core.CompilerServices.ResumableCode.TryFinallyCompensateDynamic[TData](ResumableStateMachine`1& sm, ResumptionFunc`1 mf, FSharpOption`1 savedExn) in /Users/u/code/fsharp3/src/FSharp.Core/resumable.fs:line 299
at Microsoft.FSharp.Core.CompilerServices.ResumableCode.TryFinallyAsyncDynamic[TData,T](ResumableStateMachine`1& sm, ResumableCode`2 body, ResumableCode`2 compensation) in /Users/u/code/fsharp3/src/FSharp.Core/resumable.fs:line 326
at VahterBanBot.Bot.onUpdate@391-46.Invoke(ResumableStateMachine`1& sm)
at VahterBanBot.Bot.onUpdate@389-48.Invoke(ResumableStateMachine`1& sm)
at <StartupCode$FSharp-Core>.$Tasks.initialResumptionFunc@168.Invoke(ResumableStateMachine`1& sm) in /Users/u/code/fsharp3/src/FSharp.Core/tasks.fs:line 168
at <StartupCode$FSharp-Core>.$Tasks.resumptionInfo@171.MoveNext(ResumableStateMachine`1& sm) in /Users/u/code/fsharp3/src/FSharp.Core/tasks.fs:line 177
      --- End of stack trace from previous location ---
at Program.webApp@110-2.MoveNext() in /Users/u/code/vahter-bot/src/VahterBanBot/Program.fs:line 115

After:

at VahterBanBot.Bot.onUpdate@392-1.Invoke(Activity banOnReplyActivity) in /Users/u/code/vahter-bot/src/VahterBanBot/Bot.fs:line 392
at VahterBanBot.Bot.onUpdate@391-44.Invoke(ResumableStateMachine`1& sm)
at Microsoft.FSharp.Core.CompilerServices.ResumableCode.TryFinallyAsyncDynamic[TData,T](ResumableStateMachine`1& sm, ResumableCode`2 body, ResumableCode`2 compensation) in /Users/u/code/fsharp3/src/FSharp.Core/resumable.fs:line 323
      --- End of stack trace from previous location ---
at Microsoft.FSharp.Core.CompilerServices.ResumableCode.TryFinallyCompensateDynamic[TData](ResumableStateMachine`1& sm, ResumptionFunc`1 mf, FSharpOption`1 savedExn) in /Users/u/code/fsharp3/src/FSharp.Core/resumable.fs:line 302
at Microsoft.FSharp.Core.CompilerServices.ResumableCode.TryFinallyAsyncDynamic[TData,T](ResumableStateMachine`1& sm, ResumableCode`2 body, ResumableCode`2 compensation) in /Users/u/code/fsharp3/src/FSharp.Core/resumable.fs:line 329
at VahterBanBot.Bot.onUpdate@391-46.Invoke(ResumableStateMachine`1& sm)
at VahterBanBot.Bot.onUpdate@389-48.Invoke(ResumableStateMachine`1& sm)
at <StartupCode$FSharp-Core>.$Tasks.initialResumptionFunc@168.Invoke(ResumableStateMachine`1& sm) in /Users/u/code/fsharp3/src/FSharp.Core/tasks.fs:line 168
at <StartupCode$FSharp-Core>.$Tasks.resumptionInfo@171.MoveNext(ResumableStateMachine`1& sm) in /Users/u/code/fsharp3/src/FSharp.Core/tasks.fs:line 177
      --- End of stack trace from previous location ---
at Program.webApp@110-2.MoveNext() in /Users/u/code/vahter-bot/src/VahterBanBot/Program.fs:line 115

Notice that it will now print a line exception originated from (topmost line in the stack trace above).

I want to additionally look into using the following attribute if available in code generated state machines:

https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.stacktracehiddenattribute?view=net-6.0

Checklist

@T-Gro @psfinaki @0101 @abonie @KevinRansom I am not sure if we need a dedicated set of tests for this case. We don't usually do that, and how things are thrown (stack traces in particular) is an implementation detail. I will not add it unless any of you insist.

• Test cases added (N/A)
• Release notes entry updated:

[github-actions]

❗ Release notes required

---

✅ Found changes and release notes in following paths:

Change path	Release notes path	Description
src/FSharp.Core	docs/release-notes/.FSharp.Core/8.0.300.md

[vzarytovskii]

Note: this will only affect dynamically compiled state machines

[psfinaki]

Great stuff. Regarding testing: we can always insist, the questions is - how hard is it to add them and how else verify that nothing explodes.

Personally, this feels safe to me, or more exactly small and isolated enough.

[vzarytovskii]

/run fantomas

[github-actions]

Ran fantomas: https://github.com/dotnet/fsharp/actions/runs/7614021048

[vzarytovskii]

Great stuff. Regarding testing: we can always insist, the questions is - how hard is it to add them and how else verify that nothing explodes.

Will be easy to add, but might be tricky to verify w.r.t. line numbers and such, will probably be more code for testing infrastructure than the change itself.

[0101]

Will be easy to add, but might be tricky to verify w.r.t. line numbers and such, will probably be more code for testing infrastructure than the change itself.

Shouldn't be too bad. You can access the stack trace programmatically with System.Diagnostics.StackTrace and maybe just check the method name from the first frame, or whatever else you're interested in. Don't have to care about line numbers or any other specifics.

[vzarytovskii]

Will be easy to add, but might be tricky to verify w.r.t. line numbers and such, will probably be more code for testing infrastructure than the change itself.

Shouldn't be too bad. You can access the stack trace programmatically with System.Diagnostics.StackTrace and maybe just check the method name from the first frame, or whatever else you're interested in. Don't have to care about line numbers or any other specifics.

I decided not to do that for now, since we don't have such tests anyway.