Implement Object.hasOwn and improve Object.prototype.hasOwnProperty (#1639)

* Implement Object.hasOwn and fix/add docs to Object.prototype.hasOwnProperty

* Tests for Object.hasOwn

* Improve tests for Object.prototype.hasOwnProperty

* Fix 'length' property descriptor bug

* Simplify Object.prototype.hasOwnProperty

boa/src/builtins/object/mod.rs

@@ -54,7 +54,7 @@ impl BuiltIn for Object {
         .name(Self::NAME)
         .length(Self::LENGTH)
         .inherit(None)
-        .method(Self::has_own_property, "hasOwnProperty", 0)
+        .method(Self::has_own_property, "hasOwnProperty", 1)
         .method(Self::property_is_enumerable, "propertyIsEnumerable", 0)
         .method(Self::to_string, "toString", 0)
         .method(Self::value_of, "valueOf", 0)
@@ -87,6 +87,7 @@ impl BuiltIn for Object {
         )
         .static_method(Self::get_own_property_names, "getOwnPropertyNames", 1)
         .static_method(Self::get_own_property_symbols, "getOwnPropertySymbols", 1)
+        .static_method(Self::has_own, "hasOwn", 2)
         .build();
 
         object.into()
@@ -495,7 +496,7 @@ impl Object {
         Ok(format!("[object {}]", tag_str).into())
     }
 
-    /// `Object.prototype.hasOwnPrototype( property )`
+    /// `Object.prototype.hasOwnProperty( property )`
     ///
     /// The method returns a boolean indicating whether the object has the specified property
     /// as its own property (as opposed to inheriting it).
@@ -511,12 +512,13 @@ impl Object {
         args: &[JsValue],
         context: &mut Context,
     ) -> JsResult<JsValue> {
-        let key = args
-            .get(0)
-            .unwrap_or(&JsValue::undefined())
-            .to_property_key(context)?;
+        // 1. Let P be ? ToPropertyKey(V).
+        let key = args.get_or_undefined(0).to_property_key(context)?;
+
+        // 2. Let O be ? ToObject(this value).
         let object = this.to_object(context)?;
 
+        // 3. Return ? HasOwnProperty(O, P).
         Ok(object.has_own_property(key, context)?.into())
     }
 
@@ -858,6 +860,25 @@ impl Object {
         let o = args.get_or_undefined(0);
         get_own_property_keys(o, PropertyKeyType::Symbol, context)
     }
+
+    /// `Object.hasOwn( object, property )`
+    ///
+    /// More information:
+    ///  - [ECMAScript reference][spec]
+    ///  - [MDN documentation][mdn]
+    ///
+    /// [spec]: https://tc39.es/ecma262/#sec-object.hasown
+    /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwn
+    pub fn has_own(_: &JsValue, args: &[JsValue], context: &mut Context) -> JsResult<JsValue> {
+        // 1. Let obj be ? ToObject(O).
+        let obj = args.get_or_undefined(0).to_object(context)?;
+
+        // 2. Let key be ? ToPropertyKey(P).
+        let key = args.get_or_undefined(1).to_property_key(context)?;
+
+        // 3. Return ? HasOwnProperty(obj, key).
+        Ok(obj.has_own_property(key, context)?.into())
+    }
 }
 
 /// The abstract operation ObjectDefineProperties

boa/src/builtins/object/tests.rs

@@ -93,30 +93,61 @@ fn object_is() {
     assert_eq!(forward(&mut context, "Object.is(undefined)"), "true");
     assert!(context.global_object().is_global());
 }
+
 #[test]
 fn object_has_own_property() {
-    let mut context = Context::new();
-    let init = r#"
-        let x = { someProp: 1, undefinedProp: undefined, nullProp: null };
+    let scenario = r#"
+        let symA = Symbol('a');
+        let symB = Symbol('b');
+
+        let x = {
+            undefinedProp: undefined,
+            nullProp: null,
+            someProp: 1,
+            [symA]: 2,
+            100: 3,
+        };
     "#;
 
-    eprintln!("{}", forward(&mut context, init));
-    assert_eq!(
-        forward(&mut context, "x.hasOwnProperty('someProp')"),
-        "true"
-    );
-    assert_eq!(
-        forward(&mut context, "x.hasOwnProperty('undefinedProp')"),
-        "true"
-    );
-    assert_eq!(
-        forward(&mut context, "x.hasOwnProperty('nullProp')"),
-        "true"
-    );
-    assert_eq!(
-        forward(&mut context, "x.hasOwnProperty('hasOwnProperty')"),
-        "false"
-    );
+    check_output(&[
+        TestAction::Execute(scenario),
+        TestAction::TestEq("x.hasOwnProperty('hasOwnProperty')", "false"),
+        TestAction::TestEq("x.hasOwnProperty('undefinedProp')", "true"),
+        TestAction::TestEq("x.hasOwnProperty('nullProp')", "true"),
+        TestAction::TestEq("x.hasOwnProperty('someProp')", "true"),
+        TestAction::TestEq("x.hasOwnProperty(symB)", "false"),
+        TestAction::TestEq("x.hasOwnProperty(symA)", "true"),
+        TestAction::TestEq("x.hasOwnProperty(1000)", "false"),
+        TestAction::TestEq("x.hasOwnProperty(100)", "true"),
+    ]);
+}
+
+#[test]
+fn object_has_own() {
+    let scenario = r#"
+        let symA = Symbol('a');
+        let symB = Symbol('b');
+
+        let x = {
+            undefinedProp: undefined,
+            nullProp: null,
+            someProp: 1,
+            [symA]: 2,
+            100: 3,
+        };
+    "#;
+
+    check_output(&[
+        TestAction::Execute(scenario),
+        TestAction::TestEq("Object.hasOwn(x, 'hasOwnProperty')", "false"),
+        TestAction::TestEq("Object.hasOwn(x, 'undefinedProp')", "true"),
+        TestAction::TestEq("Object.hasOwn(x, 'nullProp')", "true"),
+        TestAction::TestEq("Object.hasOwn(x, 'someProp')", "true"),
+        TestAction::TestEq("Object.hasOwn(x, symB)", "false"),
+        TestAction::TestEq("Object.hasOwn(x, symA)", "true"),
+        TestAction::TestEq("Object.hasOwn(x, 1000)", "false"),
+        TestAction::TestEq("Object.hasOwn(x, 100)", "true"),
+    ]);
 }
 
 #[test]