* ICSharpCode.NRefactory.CSharp.csproj:

* SpecializedCodeAction.cs:
* ConvertDecToHexAction.cs:
* GeneratePropertyAction.cs:
* CheckIfParameterIsNullAction.cs: 

* NRefactory.sln: Added specialized code action class.

ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj

@@ -363,6 +363,7 @@
     <Compile Include="Refactoring\CodeActions\ExtractMethod\ExtractMethodAction.cs" />
     <Compile Include="Refactoring\CodeActions\ExtractMethod\StaticVisitor.cs" />
     <Compile Include="Refactoring\CodeActions\ExtractMethod\VariableLookupVisitor.cs" />
+    <Compile Include="Refactoring\CodeActions\SpecializedCodeAction.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\ICSharpCode.NRefactory\ICSharpCode.NRefactory.csproj">

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/CheckIfParameterIsNullAction.cs

@@ -33,40 +33,25 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 	/// Creates a 'if (param == null) throw new System.ArgumentNullException ();' contruct for a parameter.
 	/// </summary>
 	[ContextAction("Check if parameter is null", Description = "Checks function parameter is not null.")]
-	public class CheckIfParameterIsNullAction : ICodeActionProvider
+	public class CheckIfParameterIsNullAction : SpecializedCodeAction<ParameterDeclaration>
 	{
-		public IEnumerable<CodeAction> GetActions(RefactoringContext context)
+		protected override CodeAction GetAction(RefactoringContext context, ParameterDeclaration parameter)
 		{
-			var parameter = GetParameterDeclaration(context);
-			if (parameter == null) {
-				yield break;
-			}
-			
 			var bodyStatement = parameter.Parent.GetChildByRole(Roles.Body);
-			
-			if (bodyStatement == null) {
-				yield break;
-			}
-			
+			if (bodyStatement == null)
+				return null;
 			var type = context.ResolveType(parameter.Type);
-			if (type.IsReferenceType == false || HasNullCheck(parameter)) {
-				yield break;
-			}
+			if (type.IsReferenceType == false || HasNullCheck(parameter)) 
+				return null;
 			
-			yield return new CodeAction (context.TranslateString("Add null check for parameter"), script => {
+			return new CodeAction (context.TranslateString("Add null check for parameter"), script => {
 				var statement = new IfElseStatement () {
 					Condition = new BinaryOperatorExpression (new IdentifierExpression (parameter.Name), BinaryOperatorType.Equality, new NullReferenceExpression ()),
 					TrueStatement = new ThrowStatement (new ObjectCreateExpression (context.CreateShortType("System", "ArgumentNullException"), new PrimitiveExpression (parameter.Name)))
 				};
-
 				script.AddTo(bodyStatement, statement);
 			});
 		}
-		
-		static ParameterDeclaration GetParameterDeclaration (RefactoringContext context)
-		{
-			return context.GetNode<ICSharpCode.NRefactory.CSharp.ParameterDeclaration> ();
-		}
 
 		static bool HasNullCheck (ParameterDeclaration parameter)
 		{

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/ConvertDecToHexAction.cs

@@ -37,16 +37,15 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 		public IEnumerable<CodeAction> GetActions(RefactoringContext context)
 		{
 			var pexpr = context.GetNode<PrimitiveExpression>();
-			if (pexpr == null || pexpr.LiteralValue.StartsWith("0X", System.StringComparison.OrdinalIgnoreCase)) {
+			if (pexpr == null || pexpr.LiteralValue.StartsWith("0X", System.StringComparison.OrdinalIgnoreCase))
 				yield break;
-			}
-			if (!((pexpr.Value is int) || (pexpr.Value is long) || (pexpr.Value is short) || (pexpr.Value is sbyte) ||
-				(pexpr.Value is uint) || (pexpr.Value is ulong) || (pexpr.Value is ushort) || (pexpr.Value is byte))) {
+
+			var value = pexpr.Value;
+			if (value is string)
 				yield break;
-			}
-			
+
 			yield return new CodeAction(context.TranslateString("Convert dec to hex"), script => {
-				script.Replace(pexpr, new PrimitiveExpression (pexpr.Value, string.Format("0x{0:x}", pexpr.Value)));
+				script.Replace(pexpr, new PrimitiveExpression (value, string.Format("0x{0:x}", value)));
 			});
 		}
 	}

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/GeneratePropertyAction.cs

@@ -36,7 +36,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 	{
 		public IEnumerable<CodeAction> GetActions(RefactoringContext context)
 		{
-			var initializer = GetVariableInitializer(context);
+			var initializer = context.GetNode<VariableInitializer>();
 			if (initializer == null || !initializer.NameToken.Contains(context.Location.Line, context.Location.Column)) {
 				yield break;
 			}
@@ -92,10 +92,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 				ret.Expression.IsMatch (new MemberReferenceExpression (new ThisReferenceExpression (), initializer.Name));
 		}
 		
-		VariableInitializer GetVariableInitializer (RefactoringContext context)
-		{
-			return context.GetNode<VariableInitializer> ();
-		}
+
 	}
 }
 

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/SpecializedCodeAction.cs

@@ -0,0 +1,38 @@
+using System;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	/// <summary>
+	/// A specialized code action creates a code action assoziated with one special type of ast nodes.
+	/// </summary>
+	public abstract class SpecializedCodeAction<T> : ICodeActionProvider where T : AstNode
+	{
+		/// <summary>
+		/// Gets the action for the specified ast node.
+		/// </summary>
+		/// <returns>
+		/// The code action. May return <c>null</c>, if no action can be provided.
+		/// </returns>
+		/// <param name='context'>
+		/// The refactoring conext.
+		/// </param>
+		/// <param name='node'>
+		/// The AstNode it's ensured that the node is always != null, if called.
+		/// </param>
+		protected abstract CodeAction GetAction(RefactoringContext context, T node);
+
+		#region ICodeActionProvider implementation
+		public System.Collections.Generic.IEnumerable<CodeAction> GetActions(RefactoringContext context)
+		{
+			var node = context.GetNode<T>();
+			if (node == null)
+				yield break;
+			var action = GetAction(context, node);
+			if (action == null)
+				yield break;
+			yield return action;
+		}
+		#endregion
+	}
+}
+

NRefactory.sln

@@ -122,6 +122,14 @@ Global
 	EndGlobalSection
 	GlobalSection(MonoDevelopProperties) = preSolution
 		StartupItem = ICSharpCode.NRefactory.Demo\ICSharpCode.NRefactory.Demo.csproj
+		Policies = $0
+		$0.TextStylePolicy = $1
+		$1.FileWidth = 120
+		$1.TabWidth = 4
+		$1.EolMarker = Unix
+		$1.inheritsSet = Mono
+		$1.inheritsScope = text/plain
+		$1.scope = text/plain
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE