sebastienros.jint/Jint/Runtime/Descriptors/GetSetPropertyDescriptor.cs

using Jint.Native;

namespace Jint.Runtime.Descriptors;

public sealed class GetSetPropertyDescriptor : PropertyDescriptor
{
    private JsValue? _get;
    private JsValue? _set;

    public GetSetPropertyDescriptor(JsValue? get, JsValue? set, bool? enumerable = null, bool? configurable = null)
        : base(null, writable: null, enumerable: enumerable, configurable: configurable)
    {
        _flags |= PropertyFlag.NonData;
        _get = get;
        _set = set;
    }

    internal GetSetPropertyDescriptor(JsValue? get, JsValue? set, PropertyFlag flags)
        : base(null, flags)
    {
        _flags |= PropertyFlag.NonData;
        _flags &= ~PropertyFlag.WritableSet;
        _flags &= ~PropertyFlag.Writable;
        _get = get;
        _set = set;
    }

    public GetSetPropertyDescriptor(PropertyDescriptor descriptor) : base(descriptor)
    {
        _flags |= PropertyFlag.NonData;
        _flags &= ~PropertyFlag.WritableSet;
        _flags &= ~PropertyFlag.Writable;
        _get = descriptor.Get;
        _set = descriptor.Set;
    }

    public override JsValue? Get => _get;
    public override JsValue? Set => _set;

    internal void SetGet(JsValue getter)
    {
        _get = getter;
    }

    internal void SetSet(JsValue setter)
    {
        _set = setter;
    }

    internal sealed class ThrowerPropertyDescriptor : PropertyDescriptor
    {
        private readonly Engine _engine;
        private JsValue? _thrower;

        public ThrowerPropertyDescriptor(Engine engine, PropertyFlag flags)
            : base(flags | PropertyFlag.CustomJsValue)
        {
            _flags |= PropertyFlag.NonData;
            _engine = engine;
        }

        public override JsValue Get => _thrower ??= _engine.Realm.Intrinsics.ThrowTypeError;
        public override JsValue Set => _thrower ??= _engine.Realm.Intrinsics.ThrowTypeError;

        protected internal override JsValue? CustomValue
        {
            set => Throw.InvalidOperationException("making changes to throw type error property's descriptor is not allowed");
        }
    }
}