Function test_transitivity

crates/kernel/src/equiv.rs:158–164

()

  /// Returns None if the key is not in the union-find.
  ///
  /// Like `is_equiv`, takes the lookup key by reference so callers can
  /// reuse a single `EqKey` binding across multiple queries without
  /// cloning it for each call.
  pub fn find_root_key(&mut self, key: &EqKey) -> Option<EqKey> {
    let node = *self.key_to_node.get(key)?;
    let root = self.find(node);
    Some(self.node_to_key[root])
  }

  /// Record that two composite keys are definitionally equal.