Function scatter_null_mask

datafusion/physical-expr-common/src/utils.rs:205–225

(
    src_nulls: Option<&NullBuffer>,
    mask: &BooleanBuffer,
    output_len: usize,
    selectivity: f64,
)

}

fn scatter_null_mask(
    src_nulls: Option<&NullBuffer>,
    mask: &BooleanBuffer,
    output_len: usize,
    selectivity: f64,
) -> Option<NullBuffer> {
    let false_count = output_len - mask.count_set_bits();
    let src_null_count = src_nulls.map(|n| n.null_count()).unwrap_or(0);

    if src_null_count == 0 {
        if false_count == 0 {
            None
        } else {
            Some(NullBuffer::new(mask.clone()))
        }
    } else {
        let src_nulls = src_nulls.unwrap();
        let scattered = scatter_bits(src_nulls.inner(), mask, output_len, selectivity);
        Some(NullBuffer::new(scattered)).filter(|n| n.null_count() > 0)
    }
}

fn scatter_primitive<T: ArrowPrimitiveType>(
    truthy: &PrimitiveArray<T>,