Set reasonable upper bound for roman numerals

core/src/ast.rs

@@ -2,7 +2,7 @@ use crate::error::{FendError, Interrupt};
 use crate::eval::evaluate_to_value;
 use crate::ident::Ident;
 use crate::interrupt::test_int;
-use crate::num::{Base, FormattingStyle, Number};
+use crate::num::{Base, FormattingStyle, Number, Range, RangeBound};
 use crate::result::FResult;
 use crate::scope::Scope;
 use crate::serialize::{Deserialize, Serialize};
@@ -628,6 +628,16 @@ fn evaluate_as<I: Interrupt>(
 				if a == 0 {
 					return Err(FendError::RomanNumeralZero);
 				}
+				let upper_limit = 100_000;
+				if a > upper_limit {
+					return Err(FendError::OutOfRange {
+						value: Box::new(a),
+						range: Range {
+							start: RangeBound::Closed(Box::new(1)),
+							end: RangeBound::Closed(Box::new(upper_limit)),
+						},
+					});
+				}
 				return Ok(Value::String(borrow::Cow::Owned(to_roman(a))));
 			}
 			_ => (),

core/src/num.rs

@@ -39,8 +39,8 @@ impl<T: fmt::Display + fmt::Debug + 'static> RangeBound<T> {
 
 #[derive(Debug)]
 pub(crate) struct Range<T> {
-	start: RangeBound<T>,
-	end: RangeBound<T>,
+	pub(crate) start: RangeBound<T>,
+	pub(crate) end: RangeBound<T>,
 }
 
 impl<T> Range<T> {

core/tests/integration_tests.rs

@@ -5935,4 +5935,5 @@ fn test_roman() {
 	test_eval_simple("3456 to roman", "MMMCDLVI");
 	test_eval_simple("1452 to roman", "MCDLII");
 	test_eval_simple("20002 to roman", "MMMMMMMMMMMMMMMMMMMMII");
+	expect_error("100001 to roman", Some("100001 must lie in the interval [1, 100000]"));
 }