Optionally (?) regenerate `import` attributes

[dougthor42]

🚀 feature request

Relevant Rules

Gazelle

Description

The python_root directive will tell Gazelle to include the imports attribute on generated targets. Eg:

py_library(
    ...
    imports = ["../../.."],
    ...
)

However, when the BUILD.bazel and python files are moved, these imports are not updated when Gazelle processes that directory again, even if there were changes to the python files/imports/whatnot.

Describe the solution you'd like

Hmm... one of:

1. Opt-in directive that tells Gazelle that it's OK to regenerate imports.
2. CLI arg for regenerating imports bazel run //:gazelle -- --regen-imports so that it can be run as a one-off
3. Always regenerate?

Describe alternatives you've considered

Right now I run:

bazel run //:buildozer 'remove imports' //...:*; bazel run //:gazelle

Which is fine I guess. We currently use bazel run //:gazelle in CI to check that Gazelle won't make any modifications (CI fails if the git tree is dirty after running that command).

The problem with the above command and running it in CI is that we have targets that are intentionally not managed by Gazelle. Those get modified by the buildozer command and then not fixed when running Gazelle.

I could probably update the buildozer command to ignore those unmanaged targets, but it would be quite messy - the unmanaged targets are a clusterfrack. It would be chaining bazel query to get the "exclude" syntax and then passing a list of managed targets to buildozer. Something like:

MANAGED_TARGETS=$(bazel query '//... except //foo/bar:* except //baz:* except //abc:apple')
bazel run //:buildozer 'remove imports' ${MANAGED_TARGETS}
bazel run //:gazelle

And I'd have to update that query when a new non-managed target/package is added.