fix: use correct runfiles path for venv import paths

[wade-arista]

In _make_import_path, ctx.workspace_name is always _main when evaluating the deps of targets in the main repo. This includes deps that are in external repos, e.g.

importer = use_extension("//:import.bzl", "importer")
use_repo(importer, "myrepo")

with

py_test(..., deps = ["@myrepo//foo"])

In this case, we actually want to use the label's workspace_name attr which will be the same as the runfiles path that we need for the venv import paths.

Also added a new e2e test that creates this external repo and verifies the fix. Without the fix in place, the test does fail as described in the e2e/repository-rule-deps/README.md "Repro" section.

---

Test plan

• New test case added in e2e/repository-rule-deps.
• Manually tested against bazel 6.5 and 7.0.2.

Fixes: #276

[CLAassistant]

All committers have signed the CLA.

[wade-arista]

I would like to see that the new e2e/repository-rule-deps is properly executed via the new "repository-rule-deps" check before this merges as well. I don't expect that I have permissions to run this, though.

Also, once bzlmod is enabled for . in the CI jobs, the tests can be moved out of e2e and executed directly.

[alexeagle]

Wow, nicely documented!

[scasagrande]

thanks @wade-arista , I was in the process of fixing this same issue, but you did a much better job than I had time for 😄

[wade-arista]

thanks @wade-arista , I was in the process of fixing this same issue, but you did a much better job than I had time for 😄

sure thing! Sorry, I had meant to post a link to discourse on #276 where we were discussing a PR, but then I forgot.

Hopefully this is the same thing fix you had in mind?

[scasagrande]

Yeah I believe this covers my case but I will have to double check just to make sure.

I did notice a further issue in my testing. After patching importing a py_libary from another workspace, I saw that the dependencies of this library not being picked up correctly. I'll take a look if that is still the case and raise a separate issue if so.