use alloc::borrow::ToOwned;
use crate::query::label_text;
use crate::syntax::builders::unary_expression::build_unary_expression_node;
use crate::syntax::fields::go::unary_expression;
use crate::syntax::fields::Field;
use crate::syntax::{SyntaxGraphArgs, SyntaxGraphError};
use crate::NodeId;
const OPTIONAL_OPERATOR: Field<false> = Field::new("operator_id");
pub fn reader(
args: &mut SyntaxGraphArgs<'_>,
n_id: NodeId,
) -> Result<Option<NodeId>, SyntaxGraphError> {
let graph = args.ast_graph;
let operator = args
.optional_field_alt(n_id, OPTIONAL_OPERATOR)
.and_then(|id| label_text(graph, id))
.map(ToOwned::to_owned)
.unwrap_or_default();
let operand_id = args.required_field_alt(n_id, unary_expression::OPERAND)?;
build_unary_expression_node(args, n_id, operator, operand_id).map(Some)
}