Function create_from_buffers

arrow-array/src/array/map_array.rs:489–531

()

    use super::*;

    fn create_from_buffers() -> MapArray {
        // Construct key and values
        let keys_data = ArrayData::builder(DataType::Int32)
            .len(8)
            .add_buffer(Buffer::from([0, 1, 2, 3, 4, 5, 6, 7].to_byte_slice()))
            .build()
            .unwrap();
        let values_data = ArrayData::builder(DataType::UInt32)
            .len(8)
            .add_buffer(Buffer::from(
                [0u32, 10, 20, 30, 40, 50, 60, 70].to_byte_slice(),
            ))
            .build()
            .unwrap();

        // Construct a buffer for value offsets, for the nested array:
        //  [[0, 1, 2], [3, 4, 5], [6, 7]]
        let entry_offsets = Buffer::from([0, 3, 6, 8].to_byte_slice());

        let keys = Arc::new(Field::new("keys", DataType::Int32, false));
        let values = Arc::new(Field::new("values", DataType::UInt32, false));
        let entry_struct = StructArray::from(vec![
            (keys, make_array(keys_data)),
            (values, make_array(values_data)),
        ]);

        // Construct a map array from the above two
        let map_data_type = DataType::Map(
            Arc::new(Field::new(
                "entries",
                entry_struct.data_type().clone(),
                false,
            )),
            false,
        );
        let map_data = ArrayData::builder(map_data_type)
            .len(3)
            .add_buffer(entry_offsets)
            .add_child_data(entry_struct.into_data())
            .build()
            .unwrap();
        MapArray::from(map_data)
    }

    #[test]
    fn test_map_array() {