alamb commented on code in PR #9497:
URL: https://github.com/apache/arrow-rs/pull/9497#discussion_r2876499078


##########
arrow-json/src/reader/list_array.rs:
##########
@@ -93,15 +93,14 @@ impl<O: OffsetSizeTrait> ArrayDecoder for 
ListArrayDecoder<O> {
 
         let child_data = self.decoder.decode(tape, &child_pos)?;
         let nulls = nulls.as_mut().map(|x| NullBuffer::new(x.finish()));
+        let values = make_array(child_data);
+        let field = match &self.data_type {
+            DataType::List(f) | DataType::LargeList(f) => f.clone(),
+            _ => unreachable!(),
+        };
+        let offsets = 
OffsetBuffer::<O>::new(ScalarBuffer::from(offsets.finish()));
 
-        let data = ArrayDataBuilder::new(self.data_type.clone())
-            .len(pos.len())
-            .nulls(nulls)
-            .add_buffer(offsets.finish())
-            .child_data(vec![child_data]);
-
-        // Safety
-        // Validated lengths above
-        Ok(unsafe { data.build_unchecked() })
+        let array = GenericListArray::<O>::try_new(field, offsets, values, 
nulls)?;
+        Ok(array.into_data())

Review Comment:
   I think this call simply creates an ArrayData (which is necessary given the 
API) so I am not sure it actually avoids any ArrayDatas
   
   In order to avoid ArrayData we would probably need to change the signature 
of decode to return an ArrayRef directly (rather than ArrayData)



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to