jj is a really nice version control system that uses git in the background. As such it can fetch data from radicle, but jj git push fails.

jj complains about “unfamiliar output”. It apparently tries to parse some output returned by git push procelain and git-remote-rad seems to be messing up the expected output.

This is what a sequence of commands that create a “refs/patches” “branch” in jj and then pushes that into the git remote that lives in origin:

> jj bookmark create refs/patches -r @
Created 1 bookmarks pointing to zvrlxmuo db790658 refs/patches | Add `rad-patch` config snippet into `README.md`
> jj git push -r @ --remote origin --allow-new
Changes to push to origin:
  Add bookmark refs/patches to db7906586ea8
Error: Git process failed: Git push output unfamiliar:

Error: External command exited with 1

The code producing this output is in the parse_ref_pushes in git_subprocess.rs in the jj repo (https://github.com/jj-vcs/jj.git for your convenience).

It apparently expects the output to start with b"To ". The docs to the function says this to the expected format:

// git-push porcelain has the following format (per line)
// `<flag>\t<from>:<to>\t<summary> (<reason>)`
//
// <flag> is one of:
//     ' ' for a successfully pushed fast-forward;
//      + for a successful forced update
//      - for a successfully deleted ref
//      * for a successfully pushed new ref
//      !  for a ref that was rejected or failed to push; and
//      =  for a ref that was up to date and did not need pushing.
//
// <from>:<to> is the refspec
//
// <summary> is extra info (commit ranges or reason for rejected)
//
// <reason> is a human-readable explanation
fn parse_ref_pushes(stdout: &[u8]) -> Result<GitPushStats, GitSubprocessError> {
    if !stdout.starts_with(b"To ") {
        return Err(GitSubprocessError::External(format!(
            "Git push output unfamiliar:\n{}",
            stdout.to_str_lossy()
        )));
    }

    [...]

It would be super cool if jj could be used with radicle… going back to git is not an option for me at all :-)