feat(turbopack): Evaluate simple numeric addition

turbopack/crates/turbopack-ecmascript/src/analyzer/builtin.rs

@@ -97,6 +97,23 @@ pub fn early_replace_builtin(value: &mut JsValue) -> bool {
 /// processed.
 pub fn replace_builtin(value: &mut JsValue) -> bool {
     match value {
+        JsValue::Add(_, list) => {
+            if list.iter().all(|arg| arg.is_string() == Some(false)) {
+                // numeric addition
+                let mut sum = 0f64;
+                for arg in list {
+                    let JsValue::Constant(ConstantValue::Num(num)) = arg else {
+                        return false;
+                    };
+                    sum += num.0;
+                }
+                *value = JsValue::Constant(ConstantValue::Num(ConstantNumber(sum)));
+                return true;
+            }
+
+            false
+        }
+
         // matching property access like `obj.prop`
         // Accessing a property on something can be handled in some cases
         JsValue::Member(_, box ref mut obj, ref mut prop) => match obj {

turbopack/crates/turbopack-ecmascript/tests/analyzer/graph/nested-args/resolved-explained.snapshot

@@ -29,7 +29,7 @@ v1 = (???*0* + 2)
   ⚠️  function calls are not analysed yet
 
 v2 = (undefined | 2 | (???*0* + 1))
-- *0* (...) => (undefined | a | (r((a + 1)) + 1))((2 + 1))
+- *0* (...) => (undefined | a | (r((a + 1)) + 1))(3)
   ⚠️  recursive function call
   ⚠️  This value might have side effects
 

turbopack/crates/turbopack-tests/tests/snapshot/expression-eval/addition/input/index.js

@@ -0,0 +1,7 @@
+console.log("side effect: before")
+
+if(1 +2 !==3){
+  throw new Error("1 + 2 !== 3");
+}
+
+console.log("side effect: after");