Hacker News Reader

I spent some time looking at the arbitrary crate in Rust and was left unsatisfied at the shrinking story, which I think is 90% of the value of PBT.

Do you have a model problem which is tricky to shrink?

I implemented a stupid simple shrinker for arbitrary, and I’d love to know a specific example where it fails to shrink in a good way:

I know at lest two interesting approaches for making that way smarter, but I don’t yet have a problem where my dumb approach isn’t sufficient.

I think I'll have to try it out! I'm just dubious about approaches that don't put shrinking front and center.

Shrinking is built in to libFuzzer! (`-minimize_crash` in libFuzzer, `cargo fuzz tmin` with cargo-fuzz)

I remember libFuzzer's shrinking not doing a great job for sophisticated structured inputs, but maybe it's worth another look!