ToStringTagTests.cs

using Microsoft.VisualStudio.TestTools.UnitTesting;
using NiL.JS.Core;
using NiL.JS.Core.Interop;
using NiL.JS.Extensions;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace FunctionalTests
{
    [TestClass]
    public sealed class ToStringTagTests
    {
        [TestMethod]
        public void JSObjectMastHaveObjectTag()
        {
            var context = new Context();
            var code = @"new Object().toString()";

            var stringValue = context.Eval(code);

            Assert.AreEqual("[object Object]", stringValue.Value);
        }

        [ToStringTag("Tag")]
        private sealed class CustomObjectWithTag : JSObject
        {
            public CustomObjectWithTag()
            {
                ValueType = JSValueType.Object;
                Value = this;
            }
        }

        [TestMethod]
        public void ToStringTagShouldWorkForCustomObjects()
        {
            var context = new Context();
            context.DefineVariable("test").Assign(new CustomObjectWithTag());
            var code = @"test.toString()";

            var stringValue = context.Eval(code);

            Assert.AreEqual("[object Tag]", stringValue.Value);
        }

        private sealed class CustomObjectWithoutTag : JSObject
        {
            public CustomObjectWithoutTag()
            {
                ValueType = JSValueType.Object;
                Value = this;
            }
        }

        [TestMethod]
        public void ToStringShouldUseNameOfCustomObjectIfToStringTagNotDefined()
        {
            var context = new Context();
            context.DefineVariable("test").Assign(new CustomObjectWithoutTag());
            var code = @"test.toString()";

            var stringValue = context.Eval(code);

            Assert.AreEqual($"[object {typeof(CustomObjectWithoutTag).Name}]", stringValue.Value);
        }

        [ToStringTag("Tag")]
        private sealed class ExternTypeWithTag
        {
        }

        [TestMethod]
        public void ToStringTagShouldWorkForExternTypes()
        {
            var context = new Context();
            context.DefineVariable("test").Assign(new ExternTypeWithTag());
            var code = @"test.toString()";

            var stringValue = context.Eval(code);

            Assert.AreEqual("[object Tag]", stringValue.Value);
        }

        private sealed class ExternTypeWithoutTag
        {
        }

        [TestMethod]
        public void ToStringShouldUseNameOfTypeIfToStringTagNotDefined()
        {
            var context = new Context();
            context.DefineVariable("test").Assign(new ExternTypeWithoutTag());
            var code = @"test.toString()";

            var stringValue = context.Eval(code);

            Assert.AreEqual($"[object {typeof(ExternTypeWithoutTag).Name}]", stringValue.Value);
        }

        [TestMethod]
        public void ToStringTagShouldBeSymbol()
        {
            var context = new Context();
            context.DefineVariable("test").Assign(new ExternTypeWithTag());
            var code = @"test[Symbol.toStringTag]";

            var stringValue = context.Eval(code);

            Assert.AreEqual("Tag", stringValue.Value);
        }
    }
}