fn map_indexes()

in crypto/src/merkle/mod.rs [342:360]

• 17 lines of code
• 4 McCabe index (conditional complexity)

fn map_indexes(
    indexes: &[usize],
    tree_depth: usize,
) -> Result<BTreeMap<usize, usize>, MerkleTreeError> {
    let num_leaves = 2usize.pow(tree_depth as u32);
    let mut map = BTreeMap::new();
    for (i, index) in indexes.iter().cloned().enumerate() {
        map.insert(index, i);
        if index >= num_leaves {
            return Err(MerkleTreeError::LeafIndexOutOfBounds(num_leaves, index));
        }
    }

    if indexes.len() != map.len() {
        return Err(MerkleTreeError::DuplicateLeafIndex);
    }

    Ok(map)
}