Function run 

pub fn run(
    cfg: Option<&Config>,
    base: &Path,
    cwd: &str,
    args: &[&str],
) -> Result<Option<String>, String>

The dry run from cwd, or None when it routes off or elsewhere (module doc).

Errors

Bad arguments, a cwd outside git, a session that did not start here, a range git cannot list.