Function test_cast_list_view_struct

datafusion/common/src/nested_struct.rs:1264–1308

()

    #[test]
    fn test_cast_list_view_struct() {
        // Build a ListView<Struct{a: Int32}> and cast to
        // ListView<Struct{a: Int64, b: Utf8}>.
        let struct_arr = StructArray::from(vec![(
            arc_field("a", DataType::Int32),
            Arc::new(Int32Array::from(vec![1, 2, 3])) as ArrayRef,
        )]);

        let source_field =
            arc_field("item", struct_type(vec![field("a", DataType::Int32)]));
        let target_field = arc_field(
            "item",
            struct_type(vec![
                field("a", DataType::Int64),
                field("b", DataType::Utf8),
            ]),
        );

        // Two list-view entries: [0..2] and [2..3]
        let list_view = ListViewArray::new(
            source_field,
            ScalarBuffer::from(vec![0i32, 2]),
            ScalarBuffer::from(vec![2i32, 1]),
            Arc::new(struct_arr),
            None,
        );
        let source_col: ArrayRef = Arc::new(list_view);

        let target_type = DataType::ListView(target_field);

        let result =
            cast_column(&source_col, &target_type, &DEFAULT_CAST_OPTIONS).unwrap();
        let result_lv = result.as_any().downcast_ref::<ListViewArray>().unwrap();
        assert_eq!(result_lv.len(), 2);

        let struct_values = result_lv
            .values()
            .as_any()
            .downcast_ref::<StructArray>()
            .unwrap();
        let a_col = get_column_as!(&struct_values, "a", Int64Array);
        assert_eq!(a_col.values(), &[1, 2, 3]);
        let b_col = get_column_as!(&struct_values, "b", StringArray);
        assert!(b_col.iter().all(|v| v.is_none()));
    }

    #[test]
    fn test_requires_nested_struct_cast() {