Document behavior of option case sensitivity

ILSpy.Tests/CommandLineArgumentsTests.cs

@@ -1,4 +1,6 @@
-using FluentAssertions;
+using System;
+
+using FluentAssertions;
 
 using NUnit.Framework;
 
@@ -36,6 +38,22 @@ namespace ICSharpCode.ILSpy.Tests
 			cmdLineArgs.NavigateTo.Should().BeEquivalentTo(navigateTo);
 		}
 
+		[Test]
+		public void VerifyNavigateToOption_NoneTest_Matching_VSAddin()
+		{
+			var cmdLineArgs = new CommandLineArguments(new string[] { "--navigateto:none" });
+			cmdLineArgs.NavigateTo.Should().BeEquivalentTo("none");
+		}
+
+		[Test]
+		public void VerifyCaseSensitivityOfOptionsThrows()
+		{
+			Action act = () => new CommandLineArguments(new string[] { "--navigateTo:none" });
+
+			act.Should().Throw<McMaster.Extensions.CommandLineUtils.UnrecognizedCommandParsingException>()
+				.WithMessage("Unrecognized option '--navigateTo:none'");
+		}
+
 		[Test]
 		public void VerifySearchOption()
 		{

ILSpy/CommandLineArguments.cs

@@ -39,6 +39,9 @@ namespace ICSharpCode.ILSpy
 			var app = new CommandLineApplication() {
 				// https://natemcmaster.github.io/CommandLineUtils/docs/response-file-parsing.html?tabs=using-attributes
 				ResponseFileHandling = ResponseFileHandling.ParseArgsAsSpaceSeparated,
+
+				// Note: options are case-sensitive (!), and, default behavior would be UnrecognizedArgumentHandling.Throw on Parse()
+				// UnrecognizedArgumentHandling = UnrecognizedArgumentHandling.CollectAndContinue
 			};
 
 			var oForceNewInstance = app.Option("--newinstance",