Function test_write_csv_decimal

arrow-csv/src/writer.rs:750–810

()

    #[test]
    fn test_write_csv_decimal() {
        let schema = Schema::new(vec![
            Field::new("c1", DataType::Decimal32(9, 6), true),
            Field::new("c2", DataType::Decimal64(17, 6), true),
            Field::new("c3", DataType::Decimal128(38, 6), true),
            Field::new("c4", DataType::Decimal256(76, 6), true),
        ]);

        let mut c1_builder = Decimal32Builder::new().with_data_type(DataType::Decimal32(9, 6));
        c1_builder.extend(vec![Some(-3335724), Some(2179404), None, Some(290472)]);
        let c1 = c1_builder.finish();

        let mut c2_builder = Decimal64Builder::new().with_data_type(DataType::Decimal64(17, 6));
        c2_builder.extend(vec![Some(-3335724), Some(2179404), None, Some(290472)]);
        let c2 = c2_builder.finish();

        let mut c3_builder = Decimal128Builder::new().with_data_type(DataType::Decimal128(38, 6));
        c3_builder.extend(vec![Some(-3335724), Some(2179404), None, Some(290472)]);
        let c3 = c3_builder.finish();

        let mut c4_builder = Decimal256Builder::new().with_data_type(DataType::Decimal256(76, 6));
        c4_builder.extend(vec![
            Some(i256::from_i128(-3335724)),
            Some(i256::from_i128(2179404)),
            None,
            Some(i256::from_i128(290472)),
        ]);
        let c4 = c4_builder.finish();

        let batch = RecordBatch::try_new(
            Arc::new(schema),
            vec![Arc::new(c1), Arc::new(c2), Arc::new(c3), Arc::new(c4)],
        )
        .unwrap();

        let mut file = tempfile::tempfile().unwrap();

        let mut writer = Writer::new(&mut file);
        let batches = vec![&batch, &batch];
        for batch in batches {
            writer.write(batch).unwrap();
        }
        drop(writer);

        // check that file was written successfully
        file.rewind().unwrap();
        let mut buffer: Vec<u8> = vec![];
        file.read_to_end(&mut buffer).unwrap();

        let expected = r#"c1,c2,c3,c4
-3.335724,-3.335724,-3.335724,-3.335724
2.179404,2.179404,2.179404,2.179404
,,,
0.290472,0.290472,0.290472,0.290472
-3.335724,-3.335724,-3.335724,-3.335724
2.179404,2.179404,2.179404,2.179404
,,,
0.290472,0.290472,0.290472,0.290472