Function interleave_fallback

arrow-select/src/interleave.rs:596–627

Fallback implementation of interleave using [`MutableArrayData`]

(
    values: &[&dyn Array],
    indices: &[(usize, usize)],
)

/// Fallback implementation of interleave using [`MutableArrayData`]
fn interleave_fallback(
    values: &[&dyn Array],
    indices: &[(usize, usize)],
) -> Result<ArrayRef, ArrowError> {
    let arrays: Vec<_> = values.iter().map(|x| x.to_data()).collect();
    let arrays: Vec<_> = arrays.iter().collect();
    let mut array_data = MutableArrayData::new(arrays, false, indices.len());

    let mut cur_array = indices[0].0;
    let mut start_row_idx = indices[0].1;
    let mut end_row_idx = start_row_idx + 1;

    for (array, row) in indices.iter().skip(1).copied() {
        if array == cur_array && row == end_row_idx {
            // subsequent row in same batch
            end_row_idx += 1;
            continue;
        }

        // emit current batch of rows for current buffer
        array_data.extend(cur_array, start_row_idx, end_row_idx);

        // start new batch of rows
        cur_array = array;
        start_row_idx = row;
        end_row_idx = start_row_idx + 1;
    }

    // emit final batch of rows
    array_data.extend(cur_array, start_row_idx, end_row_idx);
    Ok(make_array(array_data.freeze()))
}

/// Fallback implementation for interleaving dictionaries when it was determined
/// that the dictionary values should not be merged. This implementation concatenates