From e0c62dfdfc2455f325cae62ea2e77758554e171e Mon Sep 17 00:00:00 2001
From: Лач <iam@lach.pw>
Date: Wed, 01 Jul 2020 18:35:30 +0000
Subject: [PATCH] feat(evaluator): number overflow checks


---
--- a/crates/jrsonnet-evaluator/src/evaluate.rs
+++ b/crates/jrsonnet-evaluator/src/evaluate.rs
@@ -92,7 +92,7 @@
 
 		(Val::Obj(v1), Val::Obj(v2)) => Val::Obj(v2.with_super(v1.clone())),
 		(Val::Arr(a), Val::Arr(b)) => Val::Arr(Rc::new([&a[..], &b[..]].concat())),
-		(Val::Num(v1), Val::Num(v2)) => Val::Num(v1 + v2),
+		(Val::Num(v1), Val::Num(v2)) => Val::new_checked_num(v1 + v2)?,
 		_ => create_error_result(Error::BinaryOperatorDoesNotOperateOnValues(
 			BinaryOpType::Add,
 			a.value_type()?,
@@ -135,15 +135,15 @@
 		(Val::Str(v1), BinaryOpType::Gte, Val::Str(v2)) => Val::Bool(v1 >= v2),
 
 		// Num X Num
-		(Val::Num(v1), BinaryOpType::Mul, Val::Num(v2)) => Val::Num(v1 * v2),
+		(Val::Num(v1), BinaryOpType::Mul, Val::Num(v2)) => Val::new_checked_num(v1 * v2)?,
 		(Val::Num(v1), BinaryOpType::Div, Val::Num(v2)) => {
 			if *v2 <= f64::EPSILON {
 				create_error_result(crate::Error::DivisionByZero)?
 			}
-			Val::Num(v1 / v2)
+			Val::new_checked_num(v1 / v2)?
 		}
 
-		(Val::Num(v1), BinaryOpType::Sub, Val::Num(v2)) => Val::Num(v1 - v2),
+		(Val::Num(v1), BinaryOpType::Sub, Val::Num(v2)) => Val::new_checked_num(v1 - v2)?,
 
 		(Val::Num(v1), BinaryOpType::Lt, Val::Num(v2)) => Val::Bool(v1 < v2),
 		(Val::Num(v1), BinaryOpType::Gt, Val::Num(v2)) => Val::Bool(v1 > v2),
@@ -644,7 +644,7 @@
 		Literal(LiteralType::Null) => Val::Null,
 		Parened(e) => evaluate(context, e)?,
 		Str(v) => Val::Str(v.clone()),
-		Num(v) => Val::Num(*v),
+		Num(v) => Val::new_checked_num(*v)?,
 		BinaryOp(v1, o, v2) => evaluate_binary_op_special(context, &v1, *o, &v2)?,
 		UnaryOp(o, v) => evaluate_unary_op(*o, &evaluate(context, v)?)?,
 		Var(name) => push(loc, "var", || {
--- a/crates/jrsonnet-evaluator/src/val.rs
+++ b/crates/jrsonnet-evaluator/src/val.rs
@@ -134,6 +134,15 @@
 	};
 }
 impl Val {
+	/// Creates Val::Num after checking for overflow. As numbers are f64, we can just check for finity
+	pub fn new_checked_num(num: f64) -> Result<Val> {
+		if num.is_finite() {
+			Ok(Val::Num(num))
+		} else {
+			create_error_result(Error::RuntimeError("overflow".into()))
+		}
+	}
+
 	pub fn assert_type(&self, context: &'static str, val_type: ValType) -> Result<()> {
 		let this_type = self.value_type()?;
 		if this_type != val_type {

-- 
gitstuff