pub fn prepare(p: &Prepare<'_>) -> Result<Option<Prepared>, Failure>Expand description
Prepares the worktree: each root’s folder installed, unless the record
shows it installed for the same lockfile and still there. None: the
project has no root that needs it (Go, Rust).
§Errors
A lockfile is missing, a folder is not the worktree’s own, or an
install failed: the task stops (PREPARE-FAILED), never a verdict.