LibJS: Convert is_extensible() to ThrowCompletionOr

Author: https://github.com/linusg
Commit: https://github.com/SerenityOS/serenity/commit/9b6c09e2c4f
Pull-request: https://github.com/SerenityOS/serenity/pull/10327
Reviewed-by: https://github.com/IdanHo ✅

Userland/Libraries/LibJS/Runtime/GlobalEnvironment.cpp

@@ -143,7 +143,7 @@ bool GlobalEnvironment::can_declare_global_var(FlyString const& name) const
         return {};
     if (has_property)
         return true;
-    return global_object.is_extensible();
+    return TRY_OR_DISCARD(global_object.is_extensible());
 }
 
 // 9.1.1.4.16 CanDeclareGlobalFunction ( N ), https://tc39.es/ecma262/#sec-candeclareglobalfunction
@@ -152,7 +152,7 @@ bool GlobalEnvironment::can_declare_global_function(FlyString const& name) const
     auto& global_object = m_object_record->binding_object();
     auto existing_prop = TRY_OR_DISCARD(global_object.internal_get_own_property(name));
     if (!existing_prop.has_value())
-        return global_object.is_extensible();
+        return TRY_OR_DISCARD(global_object.is_extensible());
     if (*existing_prop->configurable)
         return true;
     if (existing_prop->is_data_descriptor() && *existing_prop->writable && *existing_prop->enumerable)
@@ -168,9 +168,10 @@ void GlobalEnvironment::create_global_var_binding(FlyString const& name, bool ca
     bool has_property = global_object.has_own_property(name);
     if (vm.exception())
         return;
-    bool extensible = global_object.is_extensible();
-    if (vm.exception())
+    auto extensible_or_error = global_object.is_extensible();
+    if (extensible_or_error.is_error())
         return;
+    auto extensible = extensible_or_error.release_value();
     if (!has_property && extensible) {
         m_object_record->create_mutable_binding(m_object_record->global_object(), name, can_be_deleted);
         if (vm.exception())

Userland/Libraries/LibJS/Runtime/Object.cpp

@@ -68,9 +68,10 @@ Object::~Object()
 // 7.2 Testing and Comparison Operations, https://tc39.es/ecma262/#sec-testing-and-comparison-operations
 
 // 7.2.5 IsExtensible ( O ), https://tc39.es/ecma262/#sec-isextensible-o
-bool Object::is_extensible() const
+ThrowCompletionOr<bool> Object::is_extensible() const
 {
-    return TRY_OR_DISCARD(internal_is_extensible());
+    // 1. Return ? O.[[IsExtensible]]().
+    return internal_is_extensible();
 }
 
 // 7.3 Operations on Objects, https://tc39.es/ecma262/#sec-operations-on-objects
@@ -352,17 +353,13 @@ bool Object::set_integrity_level(IntegrityLevel level)
 // 7.3.16 TestIntegrityLevel ( O, level ), https://tc39.es/ecma262/#sec-testintegritylevel
 bool Object::test_integrity_level(IntegrityLevel level) const
 {
-    auto& vm = this->vm();
-
     // 1. Assert: Type(O) is Object.
 
     // 2. Assert: level is either sealed or frozen.
     VERIFY(level == IntegrityLevel::Sealed || level == IntegrityLevel::Frozen);
 
     // 3. Let extensible be ? IsExtensible(O).
-    auto extensible = is_extensible();
-    if (vm.exception())
-        return {};
+    auto extensible = TRY_OR_DISCARD(is_extensible());
 
     // 4. If extensible is true, return false.
     // 5. NOTE: If the object is extensible, none of its properties are examined.
@@ -616,15 +613,11 @@ ThrowCompletionOr<Optional<PropertyDescriptor>> Object::internal_get_own_propert
 ThrowCompletionOr<bool> Object::internal_define_own_property(PropertyName const& property_name, PropertyDescriptor const& property_descriptor)
 {
     VERIFY(property_name.is_valid());
-    auto& vm = this->vm();
-
     // 1. Let current be ? O.[[GetOwnProperty]](P).
     auto current = TRY(internal_get_own_property(property_name));
 
     // 2. Let extensible be ? IsExtensible(O).
-    auto extensible = is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible = TRY(is_extensible());
 
     // 3. Return ValidateAndApplyPropertyDescriptor(O, P, extensible, Desc, current).
     return validate_and_apply_property_descriptor(this, property_name, extensible, property_descriptor, current);

Userland/Libraries/LibJS/Runtime/Object.h

@@ -71,7 +71,7 @@ public:
 
     // 7.2 Testing and Comparison Operations, https://tc39.es/ecma262/#sec-testing-and-comparison-operations
 
-    bool is_extensible() const;
+    ThrowCompletionOr<bool> is_extensible() const;
 
     // 7.3 Operations on Objects, https://tc39.es/ecma262/#sec-operations-on-objects
 

Userland/Libraries/LibJS/Runtime/ObjectConstructor.cpp

@@ -179,7 +179,7 @@ JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::is_extensible)
     auto argument = vm.argument(0);
     if (!argument.is_object())
         return Value(false);
-    return Value(argument.as_object().is_extensible());
+    return Value(TRY_OR_DISCARD(argument.as_object().is_extensible()));
 }
 
 // 20.1.2.15 Object.isFrozen ( O ), https://tc39.es/ecma262/#sec-object.isfrozen

Userland/Libraries/LibJS/Runtime/ProxyObject.cpp

@@ -76,9 +76,7 @@ ThrowCompletionOr<Object*> ProxyObject::internal_get_prototype_of() const
         return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyGetPrototypeOfReturn);
 
     // 9. Let extensibleTarget be ? IsExtensible(target).
-    auto extensible_target = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible_target = TRY(m_target.is_extensible());
 
     // 10. If extensibleTarget is true, return handlerProto.
     if (extensible_target)
@@ -128,9 +126,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_set_prototype_of(Object* prototype
         return false;
 
     // 10. Let extensibleTarget be ? IsExtensible(target).
-    auto extensible_target = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible_target = TRY(m_target.is_extensible());
 
     // 11. If extensibleTarget is true, return true.
     if (extensible_target)
@@ -175,9 +171,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_is_extensible() const
     auto trap_result = TRY(vm.call(*trap, &m_handler, &m_target)).to_boolean();
 
     // 8. Let targetResult be ? IsExtensible(target).
-    auto target_result = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto target_result = TRY(m_target.is_extensible());
 
     // 9. If SameValue(booleanTrapResult, targetResult) is false, throw a TypeError exception.
     if (trap_result != target_result)
@@ -217,9 +211,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_prevent_extensions()
     // 8. If booleanTrapResult is true, then
     if (trap_result) {
         // a. Let extensibleTarget be ? IsExtensible(target).
-        auto extensible_target = m_target.is_extensible();
-        if (auto* exception = vm.exception())
-            return throw_completion(exception->value());
+        auto extensible_target = TRY(m_target.is_extensible());
 
         // b. If extensibleTarget is true, throw a TypeError exception.
         if (extensible_target)
@@ -278,9 +270,7 @@ ThrowCompletionOr<Optional<PropertyDescriptor>> ProxyObject::internal_get_own_pr
             return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyGetOwnDescriptorNonConfigurable);
 
         // c. Let extensibleTarget be ? IsExtensible(target).
-        auto extensible_target = m_target.is_extensible();
-        if (auto* exception = vm.exception())
-            return throw_completion(exception->value());
+        auto extensible_target = TRY(m_target.is_extensible());
 
         // d. If extensibleTarget is false, throw a TypeError exception.
         if (!extensible_target)
@@ -291,9 +281,7 @@ ThrowCompletionOr<Optional<PropertyDescriptor>> ProxyObject::internal_get_own_pr
     }
 
     // 12. Let extensibleTarget be ? IsExtensible(target).
-    auto extensible_target = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible_target = TRY(m_target.is_extensible());
 
     // 13. Let resultDesc be ? ToPropertyDescriptor(trapResultObj).
     auto result_desc = to_property_descriptor(global_object, trap_result);
@@ -370,9 +358,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_define_own_property(PropertyName c
     auto target_descriptor = TRY(m_target.internal_get_own_property(property_name));
 
     // 12. Let extensibleTarget be ? IsExtensible(target).
-    auto extensible_target = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible_target = TRY(m_target.is_extensible());
 
     // 14. Else, let settingConfigFalse be false.
     bool setting_config_false = false;
@@ -457,9 +443,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_has_property(PropertyName const& p
                 return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyHasExistingNonConfigurable);
 
             // ii. Let extensibleTarget be ? IsExtensible(target).
-            auto extensible_target = m_target.is_extensible();
-            if (auto* exception = vm.exception())
-                return throw_completion(exception->value());
+            auto extensible_target = TRY(m_target.is_extensible());
 
             // iii. If extensibleTarget is false, throw a TypeError exception.
             if (!extensible_target)
@@ -648,9 +632,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_delete(PropertyName const& propert
         return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyDeleteNonConfigurable);
 
     // 13. Let extensibleTarget be ? IsExtensible(target).
-    auto extensible_target = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible_target = TRY(m_target.is_extensible());
 
     // 14. If extensibleTarget is false, throw a TypeError exception.
     if (!extensible_target)
@@ -704,9 +686,7 @@ ThrowCompletionOr<MarkedValueList> ProxyObject::internal_own_property_keys() con
         return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyOwnPropertyKeysDuplicates);
 
     // 10. Let extensibleTarget be ? IsExtensible(target).
-    auto extensible_target = m_target.is_extensible();
-    if (auto* exception = vm.exception())
-        return throw_completion(exception->value());
+    auto extensible_target = TRY(m_target.is_extensible());
 
     // 11. Let targetKeys be ? target.[[OwnPropertyKeys]]().
     auto target_keys = TRY(m_target.internal_own_property_keys());