Cleanup iterator helpers

core/engine/src/builtins/array/array_iterator.rs

@@ -39,13 +39,7 @@ pub(crate) struct ArrayIterator {
 impl IntrinsicObject for ArrayIterator {
     fn init(realm: &Realm) {
         BuiltInBuilder::with_intrinsic::<Self>(realm)
-            .prototype(
-                realm
-                    .intrinsics()
-                    .objects()
-                    .iterator_prototypes()
-                    .iterator(),
-            )
+            .prototype(realm.intrinsics().constructors().iterator().prototype())
             .static_method(Self::next, js_string!("next"), 0)
             .static_property(
                 JsSymbol::to_string_tag(),

core/engine/src/builtins/builder.rs

@@ -178,11 +178,6 @@ pub(crate) struct BuiltInConstructorWithPrototype<'ctx> {
     __proto__: JsPrototype,
     inherits: Option<JsObject>,
     attributes: Attribute,
-    /// If `Some`, the `constructor` property on the prototype will be installed
-    /// as a get/set accessor pair instead of as a writable data property.
-    /// This is needed by `Iterator.prototype.constructor` per the spec
-    /// (web-compat requirement).
-    constructor_accessor: Option<(JsFunction, JsFunction)>,
 }
 
 #[allow(dead_code)]
@@ -199,13 +194,6 @@ impl BuiltInConstructorWithPrototype<'_> {
     /// See [`BuiltInConstructorWithPrototype::build`].
     const OWN_PROTOTYPE_STORAGE_SLOTS: usize = 1;
 
-    /// The number of storage slots properties that are always present in a
-    /// standard constructor's prototype object when `constructor` is installed
-    /// as a get/set **accessor** property (two slots: getter + setter).
-    ///
-    /// See [`BuiltInConstructorWithPrototype::constructor_accessor`].
-    const OWN_PROTOTYPE_STORAGE_SLOTS_ACCESSOR: usize = 2;
-
     /// Specify how many arguments the constructor function takes.
     ///
     /// Default is `0`.
@@ -390,25 +378,6 @@ impl BuiltInConstructorWithPrototype<'_> {
         self
     }
 
-    /// Installs `Iterator.prototype.constructor` (or any analogous property) as a
-    /// configurable, non-enumerable **accessor** descriptor instead of the default
-    /// writable data property.
-    ///
-    /// Per the [ECMAScript spec][spec], `Iterator.prototype.constructor` must be an
-    /// accessor for web-compatibility reasons: previously the property did not exist, so
-    /// making it a setter that ignores writes to the prototype avoids breaking existing code
-    /// that assigns `Iterator.prototype.constructor = ...`.
-    ///
-    /// When this method is called the `PROTOTYPE_STORAGE_SLOTS` constant on the
-    /// implementing built-in **must** account for two extra slots (getter + setter)
-    /// instead of the usual one slot for a data property.
-    ///
-    /// [spec]: https://tc39.es/ecma262/#sec-iterator.prototype.constructor
-    pub(crate) fn constructor_accessor(mut self, get: JsFunction, set: JsFunction) -> Self {
-        self.constructor_accessor = Some((get, set));
-        self
-    }
-
     #[track_caller]
     pub(crate) fn build(mut self) {
         let length = self.length;
@@ -418,52 +387,19 @@ impl BuiltInConstructorWithPrototype<'_> {
         self = self.static_property(js_string!("name"), name, Attribute::CONFIGURABLE);
         self = self.static_property(PROTOTYPE, prototype, Attribute::empty());
 
-        // Install the `constructor` property on the prototype — either as a writable
-        // data property (the common case) or as a get/set accessor (needed by
-        // `Iterator.prototype.constructor` for web-compat, see `constructor_accessor`).
-        if let Some((get, set)) = self.constructor_accessor.take() {
-            // Accessor path: two storage slots (getter + setter).  The `CONSTRUCTOR` key
-            // must NOT already be present (no duplicate insertion).
-            let mut attributes = SlotAttributes::CONFIGURABLE;
-            attributes.set(SlotAttributes::GET, true);
-            attributes.set(SlotAttributes::SET, true);
-            debug_assert!(
-                !self
-                    .prototype_property_table
-                    .map
-                    .contains_key(&CONSTRUCTOR.into())
-            );
-            self.prototype_property_table
-                .insert(CONSTRUCTOR.into(), attributes);
-            self.prototype_storage
-                .extend([JsValue::new(get), JsValue::new(set)]);
-            #[cfg(debug_assertions)]
-            assert!(
-                self.prototype_storage.len()
-                    <= self.prototype_storage_slots_expected
-                        + Self::OWN_PROTOTYPE_STORAGE_SLOTS_ACCESSOR,
-                "expected to allocate at most {} prototype storage slots, got {}. \
-                constant {}::PROTOTYPE_STORAGE_SLOTS may need to be adjusted",
-                self.prototype_storage_slots_expected,
-                self.prototype_storage.len() - Self::OWN_PROTOTYPE_STORAGE_SLOTS_ACCESSOR,
-                self.name.display_escaped(),
-            );
-        } else {
-            // Data property path (the default).
-            let attributes = self.attributes;
-            let object = self.constructor.clone();
-            self = self.property(CONSTRUCTOR, object, attributes);
-            #[cfg(debug_assertions)]
-            assert!(
-                self.prototype_storage.len()
-                    <= self.prototype_storage_slots_expected + Self::OWN_PROTOTYPE_STORAGE_SLOTS,
-                "expected to allocate at most {} prototype storage slots, got {}. \
+        let attributes = self.attributes;
+        let object = self.constructor.clone();
+        self = self.property(CONSTRUCTOR, object, attributes);
+        #[cfg(debug_assertions)]
+        assert!(
+            self.prototype_storage.len()
+                <= self.prototype_storage_slots_expected + Self::OWN_PROTOTYPE_STORAGE_SLOTS,
+            "expected to allocate at most {} prototype storage slots, got {}. \
                 constant {}::PROTOTYPE_STORAGE_SLOTS may need to be adjusted",
-                self.prototype_storage_slots_expected,
-                self.prototype_storage.len() - Self::OWN_PROTOTYPE_STORAGE_SLOTS,
-                self.name.display_escaped(),
-            );
-        }
+            self.prototype_storage_slots_expected,
+            self.prototype_storage.len() - Self::OWN_PROTOTYPE_STORAGE_SLOTS,
+            self.name.display_escaped(),
+        );
 
         #[cfg(debug_assertions)]
         assert!(
@@ -682,7 +618,6 @@ impl<'ctx> BuiltInBuilder<'ctx, Callable<Constructor>> {
             __proto__: Some(realm.intrinsics().constructors().function().prototype()),
             inherits: Some(realm.intrinsics().constructors().object().prototype()),
             attributes: Attribute::WRITABLE | Attribute::CONFIGURABLE | Attribute::NON_ENUMERABLE,
-            constructor_accessor: None,
         }
     }
 }
@@ -730,6 +665,36 @@ impl<T> BuiltInBuilder<'_, T> {
         self
     }
 
+    /// Adds a new accessor property to the builtin object.
+    pub(crate) fn static_accessor<K>(
+        self,
+        key: K,
+        get: Option<JsFunction>,
+        set: Option<JsFunction>,
+        attribute: Attribute,
+    ) -> Self
+    where
+        K: Into<PropertyKey>,
+    {
+        let mut property = PropertyDescriptor::builder()
+            .enumerable(attribute.enumerable())
+            .configurable(attribute.configurable());
+
+        if let Some(get) = get {
+            property = property.get(get);
+        }
+
+        if let Some(set) = set {
+            property = property.set(set);
+        }
+
+        let key = key.into();
+
+        self.object.insert(key, property);
+
+        self
+    }
+
     /// Specify the `[[Prototype]]` internal field of the builtin object.
     ///
     /// Default is `Function.prototype` for constructors and `Object.prototype` for statics.

core/engine/src/builtins/generator/mod.rs

@@ -156,13 +156,7 @@ pub struct Generator {
 impl IntrinsicObject for Generator {
     fn init(realm: &Realm) {
         BuiltInBuilder::with_intrinsic::<Self>(realm)
-            .prototype(
-                realm
-                    .intrinsics()
-                    .objects()
-                    .iterator_prototypes()
-                    .iterator(),
-            )
+            .prototype(realm.intrinsics().constructors().iterator().prototype())
             .static_method(Self::next, js_string!("next"), 1)
             .static_method(Self::r#return, js_string!("return"), 1)
             .static_method(Self::throw, js_string!("throw"), 1)