pub fn which(cmd: &str) -> Option<PathBuf>Expand description
Command lookup. Re-exported so existing callers keep this path; the
implementation moved to loopsmith-util once it turned out to have been
written three times across the workspace, in three states of correctness.
Resolve a command the way a shell would: absolute paths (and anything
containing a separator) are checked directly, bare names are resolved
against PATH.
A candidate counts only if it is executable. Checking is_file() alone —
which two of the three previous copies of this function did — reports a
non-executable file on PATH as an available command, and the failure then
surfaces much later as a confusing spawn error.