Hey, as I’m pondering on how to make progress on https://github.com/pantsbuild/pants/issues/13682 I have a POC that augments the pytest command being invoked, to shove it into a

docker run

, basically. So far so good.. however, in doing so, the pytest pex should no longer be for the host platform, but for whatever platform is compatible with the docker container.

To build for a foreign platform would require using pex's --platform, which is more stringent than we want Instead, I suspect we should build the PEX directly in the Docker container like we normally would? Iirc Stu has a proposal to add engine support for running in Docker, like how the engine can use remote execution for you without you needing to change your plugin code

That sounds like more work, but also as a better approach to the whole issue 🙂

I think it's the only way to get it working because using Pex's --platform seems like a non-starter with sdists not working Alternatively, keep what you have as a proof of concept where it might not work if you're on macOS but should work on Linux

Yeah, well, it can certainly linger there, but I don’t think we want to land it or anything like that…

It's quite a project to add docker cross compilation most likely. We definitely want to do it, but it's related to remote execution in that all process executions top-to-bottom need to occur in the image/remote-host.

Given that the current iteration would be a holdover, maybe using Pex's

--platform

is feasible then. And to Keep It Simple, we could maybe have users directly put the expected

--platform

string in the target's field? No need to try to guess it based on parsing the Dockerfile imo, that's too complex