From 8beb5670888b95899abbefd8775d28b3d4e15209 Mon Sep 17 00:00:00 2001
From: Shannon Booth <shannon@serenityos.org>
Date: Thu, 2 Jan 2025 01:56:00 +1300
Subject: [PATCH] LibJS: Remove redundant completion type check in
 ScriptEvaluation

See editorial change to the ECMA-262 spec of:

https://github.com/tc39/ecma262/commit/bc5b7fda5
---
 Libraries/LibJS/Bytecode/Interpreter.cpp | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/Libraries/LibJS/Bytecode/Interpreter.cpp b/Libraries/LibJS/Bytecode/Interpreter.cpp
index 2a82237cdf6..432c62cdeb5 100644
--- a/Libraries/LibJS/Bytecode/Interpreter.cpp
+++ b/Libraries/LibJS/Bytecode/Interpreter.cpp
@@ -229,6 +229,7 @@ ThrowCompletionOr<Value> Interpreter::run(Script& script_record, GC::Ptr<Environ
 
     // 13. If result.[[Type]] is normal, then
     if (result.type() == Completion::Type::Normal) {
+        // a. Set result to Completion(Evaluation of script).
         auto executable_result = JS::Bytecode::Generator::generate_from_ast_node(vm, script, {});
 
         if (executable_result.is_error()) {
@@ -251,21 +252,21 @@ ThrowCompletionOr<Value> Interpreter::run(Script& script_record, GC::Ptr<Environ
             else
                 result = result_or_error.return_register_value;
         }
+
+        // b. If result is a normal completion and result.[[Value]] is empty, then
+        if (result.type() == Completion::Type::Normal && !result.value().has_value()) {
+            // i. Set result to NormalCompletion(undefined).
+            result = normal_completion(js_undefined());
+        }
     }
 
-    // 14. If result.[[Type]] is normal and result.[[Value]] is empty, then
-    if (result.type() == Completion::Type::Normal && !result.value().has_value()) {
-        // a. Set result to NormalCompletion(undefined).
-        result = normal_completion(js_undefined());
-    }
-
-    // 15. Suspend scriptContext and remove it from the execution context stack.
+    // 14. Suspend scriptContext and remove it from the execution context stack.
     vm.pop_execution_context();
 
-    // 16. Assert: The execution context stack is not empty.
+    // 15. Assert: The execution context stack is not empty.
     VERIFY(!vm.execution_context_stack().is_empty());
 
-    // FIXME: 17. Resume the context that is now on the top of the execution context stack as the running execution context.
+    // FIXME: 16. Resume the context that is now on the top of the execution context stack as the running execution context.
 
     // At this point we may have already run any queued promise jobs via on_call_stack_emptied,
     // in which case this is a no-op.
@@ -279,7 +280,7 @@ ThrowCompletionOr<Value> Interpreter::run(Script& script_record, GC::Ptr<Environ
 
     vm.finish_execution_generation();
 
-    // 18. Return ? result.
+    // 17. Return ? result.
     if (result.is_abrupt()) {
         VERIFY(result.type() == Completion::Type::Throw);
         return result.release_error();