Hey folks, I'm seeing issues in the build

thread 'main' panicked at 'Could not find

protoc

installation

I think we might not install protoc for python tests seems sometimes the rust is recompiling when running python tests? https://github.com/pantsbuild/pants/actions/runs/6102240853/job/16560991050

The Rust part of Pants requires

protoc

to be available as it is no longer bundled with the

prost

crate.

even weirder is that only some of the python shards feel the need to rebuild the rust

All the CI runners should have protoc installed though, no?

This seems to be regularly happening now, e.g. https://github.com/pantsbuild/pants/pull/19779 . Still not obvious why Rust code is being rebuilt 🤔

@happy-kitchen-89482 : I only had protoc installed on the jobs which I believed actually needed it. Python shards for tests were not such jobs in my original thoughts

I've added a bunch of extra prints to the bootstrapper in https://github.com/pantsbuild/pants/pull/19780, on the off chance that reveals something insightful

The work-around for now would be to install protoc in every CI job. The workflow-generator script will need calls to

install_protoc

added in more places.

Two potential fixes for the `thread 'main' panicked at 'Could not find

protoc

installation'` CI troubles: • better but potentially using a questionable assumption: https://github.com/pantsbuild/pants/pull/19784 • alternative if that's invalid: https://github.com/pantsbuild/pants/pull/19783 (The prints above did indeed provide insight)

Good detective work! Glad we have the root cause