Function test_projection_array_values

arrow-ipc/src/reader.rs:2272–2307

()

    #[test]
    fn test_projection_array_values() {
        // define schema
        let schema = create_test_projection_schema();

        // create record batch with test data
        let batch = create_test_projection_batch_data(&schema);

        // write record batch in IPC format
        let mut buf = Vec::new();
        {
            let mut writer = crate::writer::FileWriter::try_new(&mut buf, &schema).unwrap();
            writer.write(&batch).unwrap();
            writer.finish().unwrap();
        }

        // read record batch with projection
        for index in 0..12 {
            let projection = vec![index];
            let reader = FileReader::try_new(std::io::Cursor::new(buf.clone()), Some(projection));
            let read_batch = reader.unwrap().next().unwrap().unwrap();
            let projected_column = read_batch.column(0);
            let expected_column = batch.column(index);

            // check the projected column equals the expected column
            assert_eq!(projected_column.as_ref(), expected_column.as_ref());
        }

        {
            // read record batch with reversed projection
            let reader =
                FileReader::try_new(std::io::Cursor::new(buf.clone()), Some(vec![3, 2, 1]));
            let read_batch = reader.unwrap().next().unwrap().unwrap();
            let expected_batch = batch.project(&[3, 2, 1]).unwrap();
            assert_eq!(read_batch, expected_batch);
        }
    }

    #[test]
    fn test_projection_duplicate_indices() {