From 7cb63d1aae349541aabc165d8c9e5c0943e38511 Mon Sep 17 00:00:00 2001
From: HarmoGlace <23212967+HarmoGlace@users.noreply.github.com>
Date: Wed, 26 Apr 2023 11:30:16 +0200
Subject: [PATCH] Fix overflows with operators (#904)

---
 src/eval/ops.rs            | 8 ++++----
 tests/typ/compiler/ops.typ | 5 +++++
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/eval/ops.rs b/src/eval/ops.rs
index 43ee6ceb6..48e74c8ff 100644
--- a/src/eval/ops.rs
+++ b/src/eval/ops.rs
@@ -53,7 +53,7 @@ pub fn pos(value: Value) -> StrResult<Value> {
 /// Compute the negation of a value.
 pub fn neg(value: Value) -> StrResult<Value> {
     Ok(match value {
-        Int(v) => Int(-v),
+        Int(v) => Int(v.checked_neg().ok_or("value is too large")?),
         Float(v) => Float(-v),
         Length(v) => Length(-v),
         Angle(v) => Angle(-v),
@@ -70,7 +70,7 @@ pub fn add(lhs: Value, rhs: Value) -> StrResult<Value> {
         (a, None) => a,
         (None, b) => b,
 
-        (Int(a), Int(b)) => Int(a + b),
+        (Int(a), Int(b)) => Int(a.checked_add(b).ok_or("value is too large")?),
         (Int(a), Float(b)) => Float(a as f64 + b),
         (Float(a), Int(b)) => Float(a + b as f64),
         (Float(a), Float(b)) => Float(a + b),
@@ -137,7 +137,7 @@ pub fn add(lhs: Value, rhs: Value) -> StrResult<Value> {
 /// Compute the difference of two values.
 pub fn sub(lhs: Value, rhs: Value) -> StrResult<Value> {
     Ok(match (lhs, rhs) {
-        (Int(a), Int(b)) => Int(a - b),
+        (Int(a), Int(b)) => Int(a.checked_sub(b).ok_or("value is too large")?),
         (Int(a), Float(b)) => Float(a as f64 - b),
         (Float(a), Int(b)) => Float(a - b as f64),
         (Float(a), Float(b)) => Float(a - b),
@@ -165,7 +165,7 @@ pub fn sub(lhs: Value, rhs: Value) -> StrResult<Value> {
 /// Compute the product of two values.
 pub fn mul(lhs: Value, rhs: Value) -> StrResult<Value> {
     Ok(match (lhs, rhs) {
-        (Int(a), Int(b)) => Int(a * b),
+        (Int(a), Int(b)) => Int(a.checked_mul(b).ok_or("value is too large")?),
         (Int(a), Float(b)) => Float(a as f64 * b),
         (Float(a), Int(b)) => Float(a * b as f64),
         (Float(a), Float(b)) => Float(a * b),
diff --git a/tests/typ/compiler/ops.typ b/tests/typ/compiler/ops.typ
index 2bb06e4d3..937e90244 100644
--- a/tests/typ/compiler/ops.typ
+++ b/tests/typ/compiler/ops.typ
@@ -33,6 +33,11 @@
 #test((1, 2) + (3, 4), (1, 2, 3, 4))
 #test((a: 1) + (b: 2, c: 3), (a: 1, b: 2, c: 3))
 
+---
+// Error: 3-26 value is too large
+#(9223372036854775807 + 1)
+
+---
 // Subtraction.
 #test(1-4, 3*-1)
 #test(4cm - 2cm, 2cm)