using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

using System.Reflection;

using System.Collections.ObjectModel;

​

using System.Text.Json;

using System.Text.Json.Serialization;

​

​

//https://stackoverflow.com/questions/61950224/system-text-json-jsonreaderexception-isnt-found-in-namespace

​

    using NUnit.Framework;

    using NUnit.Framework.Constraints;

​

    public class FullTypeNameConstraint : Constraint

    {

        readonly string expectedFullTypeName;

        public FullTypeNameConstraint(string expectedFullTypeName) : base(expectedFullTypeName) => this.expectedFullTypeName = expectedFullTypeName;

​

        public override string DisplayName => "FullTypeNameOf";

​

        public override ConstraintResult ApplyTo<TActual>(TActual actual)

        {

            var actualTypeName = actual?.GetType().FullName;

            return new ConstraintResult(this, actualTypeName, actualTypeName == expectedFullTypeName);

        }

    }

​

    public class Is : NUnit.Framework.Is

    {

        public static FullTypeNameConstraint FullTypeNameOf(string expectedFullTypeName) => new FullTypeNameConstraint(expectedFullTypeName);

    }   

​

    public static class CustomConstraintExtensions

    {

        public static FullTypeNameConstraint FullTypeNameOf(this ConstraintExpression expression, string expectedFullTypeName)

        {

            var constraint = new FullTypeNameConstraint(expectedFullTypeName);

            expression.Append(constraint);

            return constraint;

        }

    }    

​

    class TestClass

    {

        public static void Test()

        {

            var json = @"{";

            Assert.Throws(Is.InstanceOf<JsonException>(), () => JsonDocument.Parse(json).Dispose());

            Assert.AreEqual("System.Text.Json.JsonReaderException",

                            Assert.Throws(Is.InstanceOf<JsonException>(), () => JsonDocument.Parse(json).Dispose()).GetType().FullName);

            Assert.Throws(Is.InstanceOf<JsonException>().And.Matches(new FullTypeNameConstraint("System.Text.Json.JsonReaderException")),

                          () => JsonDocument.Parse(json).Dispose());

​

            Assert.Throws(Is.InstanceOf<JsonException>().And.Matches(new FullTypeNameConstraint("System.Text.Json.JsonReaderException")),

                          () => JsonDocument.Parse(json).Dispose());

​

            Assert.Throws(Is.InstanceOf<JsonException>().And.FullTypeNameOf("System.Text.Json.JsonReaderException"), () => JsonDocument.Parse(json).Dispose());

            Assert.Throws(Is.FullTypeNameOf("System.Text.Json.JsonReaderException"), () => JsonDocument.Parse(json).Dispose());

​

            //

            Assert.That(1, Is.FullTypeNameOf(typeof(int).FullName));

            Assert.That(1, Is.InstanceOf<object>().And.Matches(new FullTypeNameConstraint(typeof(int).FullName)));

            // Should fail

            //Assert.That(1, Is.InstanceOf<object>().And.Matches(new FullTypeNameConstraint("q")));

​

            //Assert.Throws(Is.InstanceOf<JsonException>().And.Matches(new FullTypeNameConstraint("q")), () => JsonDocument.Parse(json).Dispose();

            //Assert.Throws(Is.FullTypeNameOf("q"), () => JsonDocument.Parse(json).Dispose());

        }   

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: {0} ({1})", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , GetNetCoreVersion());

            Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

        public static string GetNetCoreVersion()

        {

            //https://techblog.dorogin.com/how-to-detect-net-core-version-in-runtime-ecd65ad695be

            //

            var assembly = typeof(System.Runtime.GCSettings).GetTypeInfo().Assembly;

            var assemblyPath = assembly.CodeBase.Split(new[] { '/', '\\' }, StringSplitOptions.RemoveEmptyEntries);

            int netCoreAppIndex = Array.IndexOf(assemblyPath, "Microsoft.NETCore.App");

            if (netCoreAppIndex > 0 && netCoreAppIndex < assemblyPath.Length - 2)

                return assemblyPath[netCoreAppIndex + 1];

            return null;

        }

    }

​