presto-hive/src/main/java/io/prestosql/plugin/hive/HiveCoercionRecordCursor.java/ListCoercer/coerce
class ListCoercer:        @Override
        public void coerce(RecordCursor delegate, int field)
        {
            if (delegate.isNull(field)) {
                setIsNull(true);
                return;
            }
            Block block = (Block) delegate.getObject(field);
            if (pageBuilder.isFull()) {
                pageBuilder.reset();
            }
            BlockBuilder blockBuilder = pageBuilder.getBlockBuilder(0);
            BlockBuilder listBuilder = blockBuilder.beginBlockEntry();
            for (int i = 0; i < block.getPositionCount(); i++) {
                if (elementCoercer == null) {
                    toElementType.appendTo(block, i, listBuilder);
                }
                else {
                    if (block.isNull(i)) {
                        listBuilder.appendNull();
                    }
                    else {
                        rewriteBlock(fromElementType, toElementType, block, i, listBuilder, elementCoercer, bridgingRecordCursor);
                    }
                }
            }
            blockBuilder.closeEntry();
            pageBuilder.declarePosition();
            setObject(toType.getObject(blockBuilder, blockBuilder.getPositionCount() - 1));
        }