Dictionary Comparison Uses Wrong Values Array

[tustvold]

compare_dict_string always uses the values array of the left operand. This is incorrect.

fn compare_dict_string<'a, T>(left: &'a Array, right: &'a Array) -> DynComparator<'a>
where
    T: ArrowDictionaryKeyType,
{
    let left = left.as_any().downcast_ref::<DictionaryArray<T>>().unwrap();
    let right = right.as_any().downcast_ref::<DictionaryArray<T>>().unwrap();
    let left_keys = left.keys_array();
    let right_keys = right.keys_array();

    let left_values = StringArray::from(left.values().data().clone());
    let right_values = StringArray::from(left.values().data().clone());

    Box::new(move |i: usize, j: usize| {
        let key_left = left_keys.value(i).to_usize().unwrap();
        let key_right = right_keys.value(j).to_usize().unwrap();
        let left = left_values.value(key_left);
        let right = right_values.value(key_right);
        left.cmp(&right)
    })
}