Remove last unique shape (except global object)

boa_builtins/build.rs

@@ -620,6 +620,53 @@ fn main() -> io::Result<()> {
         .static_method(utf16!("of"))
         .build(file)?;
 
+    BuiltInBuilder::new(&context, "ARRAY_UNSCOPABLES_OBJECT")
+        .property(
+            utf16!("at"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("copyWithin"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("entries"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("fill"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("find"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("findIndex"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("flat"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("flatMap"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("includes"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("keys"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .property(
+            utf16!("values"),
+            Attribute::WRITABLE | Attribute::ENUMERABLE | Attribute::CONFIGURABLE,
+        )
+        .build(file)?;
+
     BuiltInBuilderConstructor::new(&context, "DATE")
         .static_method(utf16!("now"))
         .static_method(utf16!("parse"))

boa_engine/src/builtins/array/mod.rs

@@ -55,6 +55,47 @@ impl BuiltInObject for ArrayPrototypeValues {
     const NAME: &'static str = "values";
 }
 
+pub(crate) struct ArrayPrototypeUnscopables;
+
+impl IntrinsicObject for ArrayPrototypeUnscopables {
+    fn init(realm: &Realm) {
+        BuiltInBuilder::with_intrinsic::<Self>(
+            realm,
+            &boa_builtins::ARRAY_UNSCOPABLES_OBJECT_STATIC_SHAPE,
+        )
+        // 1. Let unscopableList be OrdinaryObjectCreate(null).
+        .no_prototype()
+        // 2. Perform ! CreateDataPropertyOrThrow(unscopableList, "at", true).
+        .static_property(true)
+        // 3. Perform ! CreateDataPropertyOrThrow(unscopableList, "copyWithin", true).
+        .static_property(true)
+        // 4. Perform ! CreateDataPropertyOrThrow(unscopableList, "entries", true).
+        .static_property(true)
+        // 5. Perform ! CreateDataPropertyOrThrow(unscopableList, "fill", true).
+        .static_property(true)
+        // 6. Perform ! CreateDataPropertyOrThrow(unscopableList, "find", true).
+        .static_property(true)
+        // 7. Perform ! CreateDataPropertyOrThrow(unscopableList, "findIndex", true).
+        .static_property(true)
+        // 8. Perform ! CreateDataPropertyOrThrow(unscopableList, "flat", true).
+        .static_property(true)
+        // 9. Perform ! CreateDataPropertyOrThrow(unscopableList, "flatMap", true).
+        .static_property(true)
+        // 10. Perform ! CreateDataPropertyOrThrow(unscopableList, "includes", true).
+        .static_property(true)
+        // 11. Perform ! CreateDataPropertyOrThrow(unscopableList, "keys", true).
+        .static_property(true)
+        // 12. Perform ! CreateDataPropertyOrThrow(unscopableList, "values", true).
+        .static_property(true)
+        // 13. Return unscopableList.
+        .build();
+    }
+
+    fn get(intrinsics: &Intrinsics) -> JsObject {
+        intrinsics.objects().array_prototype_unscopables()
+    }
+}
+
 /// JavaScript `Array` built-in implementation.
 #[derive(Debug, Clone, Copy)]
 pub(crate) struct Array;
@@ -71,7 +112,7 @@ impl IntrinsicObject for Array {
 
         let values_function = realm.intrinsics().objects().array_prototype_values();
 
-        let unscopables_object = Self::unscopables_object();
+        let unscopables_object = Self::unscopables_object(realm);
 
         BuiltInBuilder::from_standard_constructor_static_shape::<Self>(
             realm,
@@ -3031,41 +3072,8 @@ impl Array {
     ///
     /// [spec]: https://tc39.es/ecma262/#sec-array.prototype-@@unscopables
     /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/@@unscopables
-    pub(crate) fn unscopables_object() -> JsObject {
+    fn unscopables_object(realm: &Realm) -> JsObject {
-        // 1. Let unscopableList be OrdinaryObjectCreate(null).
+        ArrayPrototypeUnscopables::init(realm);
-        let unscopable_list = JsObject::with_null_proto();
+        realm.intrinsics().objects().array_prototype_unscopables()
-        let true_prop = PropertyDescriptor::builder()
-            .value(true)
-            .writable(true)
-            .enumerable(true)
-            .configurable(true);
-        {
-            let mut obj = unscopable_list.borrow_mut();
-            // 2. Perform ! CreateDataPropertyOrThrow(unscopableList, "at", true).
-            obj.insert(utf16!("at"), true_prop.clone());
-            // 3. Perform ! CreateDataPropertyOrThrow(unscopableList, "copyWithin", true).
-            obj.insert(utf16!("copyWithin"), true_prop.clone());
-            // 4. Perform ! CreateDataPropertyOrThrow(unscopableList, "entries", true).
-            obj.insert(utf16!("entries"), true_prop.clone());
-            // 5. Perform ! CreateDataPropertyOrThrow(unscopableList, "fill", true).
-            obj.insert(utf16!("fill"), true_prop.clone());
-            // 6. Perform ! CreateDataPropertyOrThrow(unscopableList, "find", true).
-            obj.insert(utf16!("find"), true_prop.clone());
-            // 7. Perform ! CreateDataPropertyOrThrow(unscopableList, "findIndex", true).
-            obj.insert(utf16!("findIndex"), true_prop.clone());
-            // 8. Perform ! CreateDataPropertyOrThrow(unscopableList, "flat", true).
-            obj.insert(utf16!("flat"), true_prop.clone());
-            // 9. Perform ! CreateDataPropertyOrThrow(unscopableList, "flatMap", true).
-            obj.insert(utf16!("flatMap"), true_prop.clone());
-            // 10. Perform ! CreateDataPropertyOrThrow(unscopableList, "includes", true).
-            obj.insert(utf16!("includes"), true_prop.clone());
-            // 11. Perform ! CreateDataPropertyOrThrow(unscopableList, "keys", true).
-            obj.insert(utf16!("keys"), true_prop.clone());
-            // 12. Perform ! CreateDataPropertyOrThrow(unscopableList, "values", true).
-            obj.insert(utf16!("values"), true_prop);
-        }
-
-        // 13. Return unscopableList.
-        unscopable_list
     }
 }

boa_engine/src/builtins/mod.rs

@@ -895,12 +895,17 @@ struct BuiltInBuilderStaticShape<'ctx> {
     object: JsObject,
     property_index: usize,
     storage: Vec<JsValue>,
-    prototype: JsObject,
+    prototype: Option<JsObject>,
 }
 
 impl BuiltInBuilderStaticShape<'_> {
     fn prototype(mut self, prototype: JsObject) -> Self {
-        self.prototype = prototype;
+        self.prototype = Some(prototype);
+        self
+    }
+
+    fn no_prototype(mut self) -> Self {
+        self.prototype = None;
         self
     }
 
@@ -953,7 +958,8 @@ impl BuiltInBuilderStaticShape<'_> {
 
         let mut object = self.object.borrow_mut();
         object.properties_mut().shape = StaticShape::new(self.shape).into();
-        self.storage.push(self.prototype.into());
+        self.storage
+            .push(self.prototype.map_or(JsValue::undefined(), Into::into));
         object.properties_mut().storage = self.storage;
     }
 }
@@ -969,7 +975,7 @@ impl<'ctx> BuiltInBuilder {
             object: I::get(realm.intrinsics()),
             storage: Vec::with_capacity(shape.storage_len),
             property_index: 0,
-            prototype: realm.intrinsics().constructors().object().prototype(),
+            prototype: Some(realm.intrinsics().constructors().object().prototype()),
         }
     }
 }

boa_engine/src/context/intrinsics.rs

@@ -776,6 +776,9 @@ pub struct IntrinsicObjects {
     /// [`%Array.prototype.values%`](https://tc39.es/ecma262/#sec-array.prototype.values)
     array_prototype_values: JsFunction,
 
+    /// [`Array.prototype[ @@unscopables ]`](https://tc39.es/ecma262/#sec-array.prototype-@@unscopables)
+    array_prototype_unscopables: JsObject,
+
     /// Cached iterator prototypes.
     iterator_prototypes: IteratorPrototypes,
 
@@ -828,6 +831,7 @@ impl Default for IntrinsicObjects {
             json: JsObject::default_with_static_shape(),
             throw_type_error: JsFunction::empty_intrinsic_function(false),
             array_prototype_values: JsFunction::empty_intrinsic_function_static_shape(false),
+            array_prototype_unscopables: JsObject::default_with_static_shape(),
             iterator_prototypes: IteratorPrototypes::default(),
             generator: JsObject::default_with_static_shape(),
             async_generator: JsObject::default_with_static_shape(),
@@ -866,6 +870,14 @@ impl IntrinsicObjects {
         self.array_prototype_values.clone()
     }
 
+    /// Gets the [`Array.prototype[ @@unscopables ]`][spec] object.
+    ///
+    /// [spec]: https://tc39.es/ecma262/#sec-array.prototype-@@unscopables
+    #[inline]
+    pub(crate) fn array_prototype_unscopables(&self) -> JsObject {
+        self.array_prototype_unscopables.clone()
+    }
+
     /// Gets the cached iterator prototypes.
     #[inline]
     pub const fn iterator_prototypes(&self) -> &IteratorPrototypes {