implement Object.prototype.propertyIsEnumerable

required by test262's propertyHelper.js

crates/dash_middle/src/interner.rs

@@ -265,7 +265,8 @@ pub mod sym {
                 one: "1",
                 getPrototypeOf,
                 isPrototypeOf,
-                arguments
+                arguments,
+                propertyIsEnumerable
             }
         ]
     }

crates/dash_vm/src/js_std/object.rs

@@ -4,7 +4,7 @@ use crate::localscope::LocalScope;
 use crate::throw;
 use crate::value::array::Array;
 use crate::value::function::native::CallContext;
-use crate::value::object::{NamedObject, Object, PropertyKey, PropertyValue};
+use crate::value::object::{NamedObject, Object, PropertyDataDescriptor, PropertyKey, PropertyValue};
 use crate::value::ops::conversions::ValueConversion;
 use crate::value::root_ext::RootErrExt;
 use crate::value::{Root, Typeof, Value, ValueContext};
@@ -208,3 +208,12 @@ pub fn is_prototype_of(cx: CallContext) -> Result<Value, Value> {
         };
     }
 }
+
+pub fn property_is_enumerable(cx: CallContext) -> Result<Value, Value> {
+    let prop = PropertyKey::from_value(cx.scope, cx.args.first().unwrap_or_undefined())?;
+    let obj = cx.this.to_object(cx.scope)?;
+    let desc = obj.get_own_property_descriptor(cx.scope, prop).root_err(cx.scope)?;
+    Ok(Value::Boolean(desc.is_some_and(|val| {
+        val.descriptor.contains(PropertyDataDescriptor::ENUMERABLE)
+    })))
+}

crates/dash_vm/src/lib.rs

@@ -256,6 +256,7 @@ impl Vm {
                 (sym::toString, scope.statics.object_to_string.clone()),
                 (sym::hasOwnProperty, scope.statics.object_has_own_property.clone()),
                 (sym::isPrototypeOf, scope.statics.object_is_prototype_of.clone()),
+                (sym::propertyIsEnumerable, scope.statics.object_property_is_enumerable.clone())
             ],
             [],
             [],

crates/dash_vm/src/statics.rs

@@ -80,6 +80,7 @@ pub struct Statics {
     pub object_entries: Handle,
     pub object_get_prototype_of: Handle,
     pub object_is_prototype_of: Handle,
+    pub object_property_is_enumerable: Handle,
     pub number_ctor: Handle,
     pub number_prototype: Handle,
     pub number_tostring: Handle,
@@ -293,6 +294,11 @@ impl Statics {
             object_entries: function(gc, sym::entries, js_std::object::entries),
             object_get_prototype_of: function(gc, sym::getPrototypeOf, js_std::object::get_prototype_of),
             object_is_prototype_of: function(gc, sym::isPrototypeOf, js_std::object::is_prototype_of),
+            object_property_is_enumerable: function(
+                gc,
+                sym::propertyIsEnumerable,
+                js_std::object::property_is_enumerable,
+            ),
             number_ctor: function(gc, sym::Number, js_std::number::constructor),
             number_prototype: builtin_object(gc, BoxedNumber::with_obj(0.0, NamedObject::null())),
             number_tostring: function(gc, sym::toString, js_std::number::to_string),

crates/dash_vm/src/value/object.rs

@@ -486,6 +486,7 @@ impl PropertyKey {
     }
 
     pub fn from_value(sc: &mut LocalScope, value: Value) -> Result<Self, Value> {
+        // TODO: call ToPrimitive as specified by ToPropertyKey in the spec?
         match value {
             Value::Symbol(s) => Ok(Self::Symbol(s)),
             other => Ok(PropertyKey::String(other.to_js_string(sc)?)),