Function visit

atomic-repository/src/apply/mod.rs:164–195

(
        hash: &Hash,
        changes: &std::collections::HashMap<Hash, Change>,
        visited: &mut HashSet<Hash>,
        in_progress: &mut HashSet<Hash>,
        order: &mut Vec<Hash>,
    )

    let mut in_progress = HashSet::new();

    fn visit(
        hash: &Hash,
        changes: &std::collections::HashMap<Hash, Change>,
        visited: &mut HashSet<Hash>,
        in_progress: &mut HashSet<Hash>,
        order: &mut Vec<Hash>,
    ) -> InsertResult<()> {
        if visited.contains(hash) {
            return Ok(());
        }
        if in_progress.contains(hash) {
            return Err(InsertError::CyclicDependency {
                message: format!("Cycle detected involving {}", hash.to_base32()),
            });
        }

        in_progress.insert(*hash);

        if let Some(change) = changes.get(hash) {
            for dep in change.dependencies() {
                if changes.contains_key(dep) {
                    visit(dep, changes, visited, in_progress, order)?;
                }
            }
        }

        in_progress.remove(hash);
        visited.insert(*hash);
        order.push(*hash);

        Ok(())
    }

    for hash in changes.keys() {
        visit(hash, changes, &mut visited, &mut in_progress, &mut order)?;