Function cycles 

pub fn cycles(
    graph: &Graph,
    allowed: &HashSet<EdgeKind>,
    members_only: bool,
) -> Vec<Violation>

Evaluate --acyclic: one Violation per dependency cycle — a strongly-connected component of two or more crates, or a self-loop — over allowed edges. Evidence is a concrete cycle path; the subject lists the crate names in the cycle. Output is sorted for determinism. When members_only is set, only cycles among workspace members are reported (the actionable form: crate cycles among third-party deps are almost always dev-dependency noise you cannot fix).