Function sort_rows

nodedb/src/data/executor/handlers/document/sort.rs:174–208

(
    rows: &mut [(String, Vec<u8>)],
    sort_keys: &[(String, bool)],
)

type SortKeyOffsets = Vec<Option<(usize, usize)>>;

pub(in crate::data::executor) fn sort_rows(
    rows: &mut [(String, Vec<u8>)],
    sort_keys: &[(String, bool)],
) {
    if sort_keys.is_empty() {
        return;
    }

    // Pre-extract sort key offsets for all rows — one scan per row instead
    // of O(N log N) scans during comparisons.
    let mut key_offsets: Vec<SortKeyOffsets> = rows
        .iter()
        .map(|(_, bytes)| {
            sort_keys
                .iter()
                .map(|(field, _)| msgpack_scan::extract_field(bytes, 0, field))
                .collect()
        })
        .collect();

    // Sort indices using pre-extracted offsets.
    let mut indices: Vec<usize> = (0..rows.len()).collect();
    indices.sort_by(|&ai, &bi| {
        compare_with_preextracted(
            &rows[ai].1,
            &key_offsets[ai],
            &rows[bi].1,
            &key_offsets[bi],
            sort_keys,
        )
    });

    // Apply permutation in-place.
    apply_permutation(rows, &mut key_offsets, indices);
}

/// Compare two docs using pre-extracted sort key offsets.
fn compare_with_preextracted(