tool report: spr

I've been using spacedentist/spr (docs) (not to be confused with ejoffe's tool of the same name) to send PRs. If you like Gerrit's model of one commit == one review, you may like spr. Phabricator's arc tool is also similar.

Behind the covers, when spr diff --cherry-pick is invoked (on HEAD), it creates a PR and puts a pointer to that PR in the form of text in HEAD's commit message. The PR actually points to a hidden spr/... branch that it's managing. When you invoke diff again on your amended commit, it figures out the PR by creating new synthetic commits in its branch. Github, which sometimes likes to lose review comments if you force push your PR branch, is none the wiser. See this issue comment for a more accurate explanation.

My full workflow involves a wrapper which uses fzf to choose any commit between origin/main...HEAD and invoke spr on that one by abusing GIT_EDITOR in an interactive rebase.