Fixed a null reference exception that occurs when the Ruby fold parser attempted to parse a require expression without any parameters following it.

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/branches/3.0@5368 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/AddIns/BackendBindings/Ruby/RubyBinding/Project/Src/RubyAstWalker.cs

@@ -45,7 +45,7 @@ namespace ICSharpCode.RubyBinding
 		protected override void Walk(MethodCall node)
 		{
 			if (node.MethodName == "require") {
-				if (!node.Arguments.IsEmpty) {
+				if (HasArguments(node)) {
 					string requireString = GetRequireString(node.Arguments.Expressions);
 					if (requireString != null) {
 						AddUsing(requireString);
@@ -55,6 +55,11 @@ namespace ICSharpCode.RubyBinding
 			base.Walk(node);
 		}
 		
+		bool HasArguments(MethodCall node)
+		{
+			return (node.Arguments != null) && (!node.Arguments.IsEmpty);
+		}
+		
 		string GetRequireString(Expression[] expressions)
 		{
 			foreach (Expression expression in expressions) {

src/AddIns/BackendBindings/Ruby/RubyBinding/Test/Parsing/ParseRequireFollowedByCommentTestFixture.cs

@@ -0,0 +1,39 @@
+// <file>
+//     <copyright see="prj:///doc/copyright.txt"/>
+//     <license see="prj:///doc/license.txt"/>
+//     <owner name="Matthew Ward" email="mrward@users.sourceforge.net"/>
+//     <version>$Revision$</version>
+// </file>
+
+using System;
+using System.Collections.Generic;
+using ICSharpCode.RubyBinding;
+using ICSharpCode.SharpDevelop.DefaultEditor.Gui.Editor;
+using ICSharpCode.SharpDevelop.Dom;
+using ICSharpCode.TextEditor.Document;
+using NUnit.Framework;
+using RubyBinding.Tests;
+
+namespace RubyBinding.Tests.Parsing
+{
+	/// <summary>
+	/// A string of the form "require #" would cause a null reference exception since the ruby ast walker tries
+	/// to use the MethodCall's Argument which is null.
+	/// </summary>
+	[TestFixture]
+	public class ParseRequireFollowedByCommentTestFixture
+	{
+		[Test]
+		public void ParseDoesNotThrowNullReferenceException()
+		{
+			string ruby = "require #";
+			
+			DefaultProjectContent projectContent = new DefaultProjectContent();
+			RubyParser parser = new RubyParser();
+			ICompilationUnit unit = null;
+		
+			Assert.DoesNotThrow(delegate { unit = parser.Parse(projectContent, @"C:\test.rb", ruby); });
+			Assert.IsNotNull(unit);
+		}
+	}
+}

src/AddIns/BackendBindings/Ruby/RubyBinding/Test/RubyBinding.Tests.csproj

@@ -312,6 +312,7 @@
     <Compile Include="Parsing\ParseClassWithCtorTestFixture.cs" />
     <Compile Include="Parsing\ParseInvalidRubyCodeTestFixture.cs" />
     <Compile Include="Parsing\ParseMethodsWithNoClassTestFixture.cs" />
+    <Compile Include="Parsing\ParseRequireFollowedByCommentTestFixture.cs" />
     <Compile Include="Parsing\ParseRequireTestFixture.cs" />
     <Compile Include="Parsing\ParseSingleClassTestFixture.cs" />
     <Compile Include="RubyAddInOptionsTestFixture.cs" />