Function fixed_size_array_reverse

datafusion/functions-nested/src/reverse.rs:264–287

(
    array: &FixedSizeListArray,
    field: &FieldRef,
)

}

fn fixed_size_array_reverse(
    array: &FixedSizeListArray,
    field: &FieldRef,
) -> Result<ArrayRef> {
    let values: &Arc<dyn Array> = array.values();

    // Since each fixed size list in the physical array is the same size and we keep the order
    // of the fixed size lists, we can reverse the indices for each fixed size list.
    let mut indices: Vec<u64> = (0..values.len() as u64).collect();
    for chunk in indices.chunks_mut(array.value_length() as usize) {
        chunk.reverse();
    }

    // Materialize values from underlying array with take
    let indices_array: ArrayRef = Arc::new(UInt64Array::from(indices));
    let values = take(&values, &indices_array, None)?;

    Ok(Arc::new(FixedSizeListArray::try_new(
        Arc::clone(field),
        array.value_length(),
        values,
        array.nulls().cloned(),
    )?))
}

#[cfg(test)]
mod tests {