Issue389_Tests.cs

using CommandLine.Text;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Xunit;

namespace CommandLine.Tests.Unit
{
	
	public class Issue389_Tests
	{

		private const int ERROR_SUCCESS = 0;

		// Test method (xUnit) which fails
		[Fact]
		public void CallMain_GiveHelpArgument_ExpectSuccess()
		{
			var result = Program.__Main(new[] { "--help" });

			Assert.Equal(ERROR_SUCCESS, result);
		}

		// main program
		internal class Program
		{


			internal static int __Main(string[] args)
			{
				bool hasError = false;
				bool helpOrVersionRequested = false;

				ParserResult<Options> parsedOptions = Parser.Default.ParseArguments<Options>(args)
					.WithNotParsed(errors => {
						helpOrVersionRequested = errors.Any(
							x => x.Tag == ErrorType.HelpRequestedError 
							|| x.Tag == ErrorType.VersionRequestedError);
					hasError = true;
				});

				if(helpOrVersionRequested)
				{
					return ERROR_SUCCESS;
				}

				// Execute as a normal call
				// ...
				return ERROR_SUCCESS;
			}

		}

		// Options
		internal class Options
		{

			[Option('c', "connectionString", Required = true, HelpText = "Texts.ExplainConnection")]
			public string ConnectionString { get; set; }

			[Option('j', "jobId", Required = true, HelpText = "Texts.ExplainJob")]
			public int JobId { get; set; }

			[Usage(ApplicationAlias = "Importer.exe")]
			public static IEnumerable<Example> Examples
			{
				get => new[] {
				  new Example("Texts.ExplainExampleExecution", new Options() {
					  ConnectionString="Server=MyServer;Database=MyDatabase",
					  JobId = 5
				  }),
			  };
			}

		}
	}
}