Function datum_to_vortex_lit

crates/paimon/src/arrow/format/vortex.rs:346–428

Convert a Paimon `Datum` to a Vortex literal `Expression`. Returns `None` for types not yet supported by this conversion.

(datum: &Datum, file_field: &DataField)

/// Convert a Paimon `Datum` to a Vortex literal `Expression`.
/// Returns `None` for types not yet supported by this conversion.
fn datum_to_vortex_lit(datum: &Datum, file_field: &DataField) -> Option<Expression> {
    use crate::spec::DataType as PaimonDataType;
    use vortex::array::dtype::Nullability;
    use vortex::array::scalar::{PValue, Scalar, ScalarValue};
    match datum {
        Datum::Bool(v) => Some(lit(*v)),
        Datum::TinyInt(v) => Some(lit(*v)),
        Datum::SmallInt(v) => Some(lit(*v)),
        Datum::Int(v) => Some(lit(*v)),
        Datum::Long(v) => Some(lit(*v)),
        Datum::Float(v) => Some(lit(*v)),
        Datum::Double(v) => Some(lit(*v)),
        Datum::String(v) => Some(lit(v.as_str())),
        Datum::Bytes(v) => Some(lit(v.as_slice())),
        // Date: stored as days since epoch (i32) in both Paimon and Vortex.
        Datum::Date(v) => {
            use vortex::extension::datetime::{Date, TimeUnit};
            let dtype =
                DType::Extension(Date::new(TimeUnit::Days, Nullability::NonNullable).erased());
            let scalar =
                Scalar::try_new(dtype, Some(ScalarValue::Primitive(PValue::I32(*v)))).ok()?;
            Some(lit(scalar))
        }
        // Time: stored as milliseconds since midnight (i32) in Paimon.
        Datum::Time(v) => {
            use vortex::extension::datetime::{Time, TimeUnit};
            let dtype = DType::Extension(
                Time::new(TimeUnit::Milliseconds, Nullability::NonNullable).erased(),
            );
            let scalar =
                Scalar::try_new(dtype, Some(ScalarValue::Primitive(PValue::I32(*v)))).ok()?;
            Some(lit(scalar))
        }
        // Timestamp: convert (millis, nanos) to the unit matching the field precision.
        //   precision 0-3 → milliseconds, 4-6 → microseconds, 7-9 → nanoseconds.
        Datum::Timestamp { millis, nanos } => {
            use vortex::extension::datetime::Timestamp;
            let precision = match file_field.data_type() {
                PaimonDataType::Timestamp(ts) => ts.precision(),
                _ => return None,
            };
            let (time_unit, value) = precision_to_time_unit_and_value(*millis, *nanos, precision);
            let dtype =
                DType::Extension(Timestamp::new(time_unit, Nullability::NonNullable).erased());
            let scalar =
                Scalar::try_new(dtype, Some(ScalarValue::Primitive(PValue::I64(value)))).ok()?;
            Some(lit(scalar))
        }
        Datum::LocalZonedTimestamp { millis, nanos } => {
            use vortex::extension::datetime::Timestamp;
            let precision = match file_field.data_type() {
                PaimonDataType::LocalZonedTimestamp(ts) => ts.precision(),
                _ => return None,
            };
            let (time_unit, value) = precision_to_time_unit_and_value(*millis, *nanos, precision);
            let dtype = DType::Extension(
                Timestamp::new_with_tz(time_unit, Some(Arc::from("UTC")), Nullability::NonNullable)
                    .erased(),