The API was originally about SHAs, rather than refs, but for protecting branches trees make sense. (You can retrieve statuses by ref, but are required to set th

The API was originally about SHAs, rather than refs, but for protecting branches trees make sense. (You can retrieve statuses by ref, but are required to set them by SHA). Since a SHA can be uniquely resolved to a tree, we're doing this under the hood rather than make a breaking API change. It also just makes more sense; nobody thinks in terms of trees day-to-day. Thanks for you comments about per-commit linting. We'll give them some thought.