[IronPython] InvalidProgramException exception with NUnit

[Fernando Correia]

Dino, thanks for your support.

The modified code still aborts under NUnit, so it is not related to
the configuration. The program runs correctly outside NUnit, but
raises an InvalidProgramException when executed as a unit test.

I had a similar problem with a previous version of IronPython that
disappeared in another release. Granted that NUnit must be doing
something to the execution context, but it would really be a shame if
code that uses IronPython could not be tested under NUnit.

Please notice that until Beta 4 this kind of test was working. The
exception started with Beta 5.

Regards.

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;
using Microsoft.Scripting.Hosting;
using Microsoft.Scripting;
using IronPython.Hosting;
using NUnit.Framework;

namespace HelloDLRWorld
{
    [TestFixture]
    public class DlrTest2
    {
        public static void Main(string[] args)
        {
            var test = new DlrTest2();
            test.ImportTest();
        }

        [Test]
        public void ImportTest()
        {
            ScriptRuntime runtime = Python.CreateRuntime();
            runtime.LoadAssembly(typeof(System.Diagnostics.Debug).Assembly);
            runtime.LoadAssembly(typeof(System.Double).Assembly);
            ScriptEngine pyEng = runtime.GetEngine("IronPython");
            ScriptSource source = pyEng.CreateScriptSourceFromString(@"
import System.Diagnostics
output='hello world from DLR/IronPython!'
System.Diagnostics.Debug.WriteLine(output)
", SourceCodeKind.Statements);
            ScriptScope scope = pyEng.CreateScope();
            source.Execute(scope);
            object outputMsg = scope.GetVariable("output");
            Console.WriteLine(outputMsg.ToString());
        }
    }
}