Method encode

arrow-avro/src/writer/encoder.rs:746–760

(&mut self, out: &mut W, idx: usize)

    }

    fn encode<W: Write + ?Sized>(&mut self, out: &mut W, idx: usize) -> Result<(), AvroError> {
        match &self.null_state {
            NullState::NonNullable => {}
            NullState::NullableNoNulls { union_value_byte } => out
                .write_all(&[*union_value_byte])
                .map_err(|e| AvroError::IoError(format!("write union value branch: {e}"), e))?,
            NullState::Nullable { nulls, null_order } if nulls.is_null(idx) => {
                return write_optional_index(out, true, *null_order); // no value to write
            }
            NullState::Nullable { null_order, .. } => {
                write_optional_index(out, false, *null_order)?;
            }
        }
        self.encoder.encode(out, idx)
    }
}

fn union_value_branch_byte(null_order: Nullability, is_null: bool) -> u8 {