Re: [RFC PATCH 1/1] check-attr: integrate with sparse-index

> Victoria is right that it is helpful to first establish test coverage of
> the builtin for correctness reasons before making this change. It helps to
> add tests for cases that would require expanding the sparse index, such as
> checking the attributes for paths outside of the sparse-checkout cone.
>
> Once the correctness tests are in place, you can then make this change to
> the builtin and add the tests that check ensure_not_expanded, since the
> change at that point is _only_ that we are allowing the builtin to
> operate upon the sparse index without expanding it immediately after read.
>
> A good example of this "final step" is [1], which updates the builtin for
> 'git diff' as well as adding _only_ the ensure_not_expanded tests.