Function create_random_map_array

arrow/src/util/data_gen.rs:392–441

(
    field: &Field,
    size: usize,
    null_density: f32,
    true_density: f32,
)

#[inline]
fn create_random_map_array(
    field: &Field,
    size: usize,
    null_density: f32,
    true_density: f32,
) -> Result<ArrayRef> {
    // Override null density with 0.0 if the array is non-nullable
    let map_null_density = match field.is_nullable() {
        true => null_density,
        false => 0.0,
    };

    let entries_field = match field.data_type() {
        DataType::Map(f, _) => f,
        _ => {
            return Err(ArrowError::InvalidArgumentError(format!(
                "Cannot create map array for field {field:?}"
            )));
        }
    };

    let (offsets, child_len) = create_random_offsets::<i32>(size, 0, 5);
    let offsets = Buffer::from(offsets.to_byte_slice());

    let entries = create_random_array(
        entries_field,
        child_len as usize,
        null_density,
        true_density,
    )?
    .to_data();

    let null_buffer = match field.is_nullable() {
        true => Some(create_random_null_buffer(size, map_null_density)),
        false => None,
    };

    let map_data = unsafe {
        ArrayData::new_unchecked(
            field.data_type().clone(),
            size,
            None,
            null_buffer,
            0,
            vec![offsets],
            vec![entries],
        )
    };
    Ok(make_array(map_data))
}

/// Generate random offsets for list arrays
fn create_random_offsets<T: OffsetSizeTrait + SampleUniform>(