Building nullable/non nullable ListArrays

[adriangb]

I’m trying to build ListArrays with various combinations of null ability for the outer and inner items, but it seems that the builder functions hardcode the assumption that it’s nullable (eg here

arrow-rs/arrow-array/src/builder/generic_list_builder.rs

Line 137 in 79bda7d

true, // TODO: find a consistent way of getting this

). It seems like I’ll have to drop down to the buffer level, but that’s complicated. Is there an easier way?