add @__FUNCTION__ macro

[MilesCranmer]

JuliaLang/julia#58940

The macro implemented here differs slightly because it needs to refer to the internal variable var"#self#", rather than the new Expr(:thisfunction) directive, as the later required parser changes to expand compatibility with callable structs.

However, the only change this means in practice is that the Compat version will throw an error in cases where the Julia 1.13.0-DEV.880 version would work. So there would not be any silent differences; only very obvious ones. I have mentioned these cases on the Compat version docstring.

[MilesCranmer]

@martinholters let me know if you have any comments. I'm eager to get this merged as I need it in a package

[martinholters]

I think the restrictions mentioned in the docstring will go largely unnoticed. Maybe add a sentence to the README, pointing to the docstring for details?

[MilesCranmer]

Thanks, done!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.78%. Comparing base (743ee8c) to head (da64166).

Additional details and impacted files

@@             Coverage Diff             @@
##           master     #841       +/-   ##
===========================================
+ Coverage   50.00%   91.78%   +41.78%     
===========================================
  Files           2        2               
  Lines         458      487       +29     
===========================================
+ Hits          229      447      +218     
+ Misses        229       40      -189     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[MilesCranmer]

@martinholters sorry for pinging but just wanted to check-in on this (usually I only have time to code on the weekend these days)