vcs-core

A unified facade over vcs-git and vcs-jj: repository detection plus a backend-agnostic handle for the operations both tools share.

It exists to lift the "detect git-vs-jj and dispatch behind one interface" layer that downstream tools kept re-implementing. Rich, tool-specific operations stay on the underlying vcs-git / vcs-jj clients, reachable through the Repo::git() / Repo::jj() escape hatches.

What it gives you

• detect(dir) -> Option<Located> — walk up from dir to find a .git/.jj repository. A .jj directory wins over .git (colocated repos are driven through jj). Pure filesystem probing, no subprocess.
• Repo — a cwd-bound handle. Open it once, then call the common surface without threading a directory through every call:

use vcs_core::Repo;

# fn main() -> vcs_core::Result<()> {
let repo = Repo::open(".")?;
println!("backend: {}", repo.kind().as_str());
# Ok(())
# }

Common surface

current_branch, trunk, changed_files, diff_stat, commit_paths, fetch, list_worktrees, create_worktree, remove_worktree — each returning backend-agnostic DTOs (FileChange, DiffStat, WorktreeInfo, …). Re-anchor a handle to a sibling directory with repo.at(other_dir).

Testing

Repo is generic over processkit::ProcessRunner. Build one from an explicit client (Repo::from_git / Repo::from_jj) with a ScriptedRunner to test dispatch hermetically, exactly as the underlying crates do.