LibJS: Use GetShadowRealmContext for PerformShadowRealmEval

Author: https://github.com/shannonbooth
Commit: 3cb62265ab
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2134
Reviewed-by: https://github.com/ADKaster ✅

Userland/Libraries/LibJS/Runtime/ShadowRealm.cpp

@@ -124,57 +124,33 @@ ThrowCompletionOr<Value> perform_shadow_realm_eval(VM& vm, StringView source_tex
     auto strict_eval = program->is_strict_mode();
 
     // 4. Let runningContext be the running execution context.
-    // NOTE: This would be unused due to step 11 and is omitted for that reason.
+    // 5. If runningContext is not already suspended, suspend runningContext.
+    // NOTE: This would be unused due to step 9 and is omitted for that reason.
 
-    // 5. Let lexEnv be NewDeclarativeEnvironment(evalRealm.[[GlobalEnv]]).
+    // 6. Let evalContext be GetShadowRealmContext(evalRealm, strictEval).
-    Environment* lexical_environment = new_declarative_environment(eval_realm.global_environment()).ptr();
+    auto eval_context = get_shadow_realm_context(eval_realm, strict_eval);
 
-    // 6. Let varEnv be evalRealm.[[GlobalEnv]].
+    // 7. Let lexEnv be evalContext's LexicalEnvironment.
-    Environment* variable_environment = &eval_realm.global_environment();
+    auto lexical_environment = eval_context->lexical_environment;
 
-    // 7. If strictEval is true, set varEnv to lexEnv.
+    // 8. Let varEnv be evalContext's VariableEnvironment.
-    if (strict_eval)
+    auto variable_environment = eval_context->variable_environment;
-        variable_environment = lexical_environment;
 
-    // 8. If runningContext is not already suspended, suspend runningContext.
+    // 9. Push evalContext onto the execution context stack; evalContext is now the running execution context.
-    // NOTE: We don't support this concept yet.
-
-    // 9. Let evalContext be a new ECMAScript code execution context.
-    auto eval_context = ExecutionContext::create();
-
-    // 10. Set evalContext's Function to null.
-    eval_context->function = nullptr;
-
-    // 11. Set evalContext's Realm to evalRealm.
-    eval_context->realm = &eval_realm;
-
-    // 12. Set evalContext's ScriptOrModule to null.
-    // Note: This is already the default value.
-
-    // 13. Set evalContext's VariableEnvironment to varEnv.
-    eval_context->variable_environment = variable_environment;
-
-    // 14. Set evalContext's LexicalEnvironment to lexEnv.
-    eval_context->lexical_environment = lexical_environment;
-
-    // Non-standard
-    eval_context->is_strict_mode = strict_eval;
-
-    // 15. Push evalContext onto the execution context stack; evalContext is now the running execution context.
     TRY(vm.push_execution_context(*eval_context, {}));
 
-    // 16. Let result be Completion(EvalDeclarationInstantiation(body, varEnv, lexEnv, null, strictEval)).
+    // 10. Let result be Completion(EvalDeclarationInstantiation(body, varEnv, lexEnv, null, strictEval)).
     auto eval_result = eval_declaration_instantiation(vm, program, variable_environment, lexical_environment, nullptr, strict_eval);
 
     Completion result;
 
-    // 17. If result.[[Type]] is normal, then
+    // 11. If result.[[Type]] is normal, then
     if (!eval_result.is_throw_completion()) {
         // a. Set result to the result of evaluating body.
         auto maybe_executable = Bytecode::compile(vm, program, FunctionKind::Normal, "ShadowRealmEval"sv);
-        if (maybe_executable.is_error())
+        if (maybe_executable.is_error()) {
             result = maybe_executable.release_error();
-        else {
+        } else {
             auto executable = maybe_executable.release_value();
 
             auto result_and_return_register = vm.bytecode_interpreter().run_executable(*executable, {});
@@ -187,24 +163,27 @@ ThrowCompletionOr<Value> perform_shadow_realm_eval(VM& vm, StringView source_tex
         }
     }
 
-    // 18. If result.[[Type]] is normal and result.[[Value]] is empty, then
+    // 12. 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());
     }
 
-    // 19. Suspend evalContext and remove it from the execution context stack.
+    // 13. Suspend evalContext and remove it from the execution context stack.
     // NOTE: We don't support this concept yet.
     vm.pop_execution_context();
 
-    // 20. Resume the context that is now on the top of the execution context stack as the running execution context.
+    // 14. Resume the context that is now on the top of the execution context stack as the running execution context.
     // NOTE: We don't support this concept yet.
 
-    // 21. If result.[[Type]] is not normal, throw a TypeError exception.
+    // 15. If result.[[Type]] is not normal, then
-    if (result.type() != Completion::Type::Normal)
+    if (result.type() != Completion::Type::Normal) {
+        // a. Let copiedError be CreateTypeErrorCopy(callerRealm, result.[[Value]]).
+        // b. Return ThrowCompletion(copiedError).
         return vm.throw_completion<TypeError>(ErrorType::ShadowRealmEvaluateAbruptCompletion);
+    }
 
-    // 22. Return ? GetWrappedValue(callerRealm, result.[[Value]]).
+    // 16. Return ? GetWrappedValue(callerRealm, result.[[Value]]).
     return get_wrapped_value(vm, caller_realm, *result.value());
 
     // NOTE: Also see "Editor's Note" in the spec regarding the TypeError above.
@@ -342,6 +321,9 @@ NonnullOwnPtr<ExecutionContext> get_shadow_realm_context(Realm& shadow_realm, bo
     // 10. Set context's PrivateEnvironment to null.
     context->private_environment = nullptr;
 
+    // Non-standard
+    context->is_strict_mode = strict_eval;
+
     // 11. Return context.
     return context;
 }