Linter: package_names: should allow leading `_`

[kevmoo]

This is very common, especially with unpublished packages used for testing.

[pq]

I tend to agree.

@jonasfj: any concerns?

[pq]

@kevmoo : to be clear, are you thinking this should be relaxed for all packages or just ones meant for publishing?

[kevmoo]

If it was just allowed on packages with publish_to: none I'd be fine w/ that.

I know we did have some packages published using _ first. @jonasfj may have thoughts.

[sigurdm]

We have https://pub.dev/packages/_dummy_pkg used for integration tests of pub. And there is the https://pub.dev/packages/_fe_analyzer_shared package.
I think we want to allow these packages. I guess the convention is that a _ prefix means end-users don't want to depend directly on that package which aligns somewhat with privacy in dart.

[pq]

OK! It sounds to me like widening the check to allow for leading underscores is the right thing to do. If there are certain packages that should not be directly depended on that feels like another check.

[jonasfj]

If there are certain packages that should not be directly depended on that feels like another check.

I don't think that needs a check. If authors document that in the README is should be fine.

The pattern of using package names starting with underscore is just a neat convention, it's not something we've formalized.