Introduced ParamRangeCheckContextAction.

src/AddIns/BackendBindings/CSharpBinding/Project/CSharpBinding.addin

@@ -316,6 +316,7 @@
 		<CSharpCodeActionProvider class = "ICSharpCode.NRefactory.CSharp.Refactoring.UseVarKeywordAction" />
 		<Class class="CSharpBinding.Refactoring.MoveTypeToFileContextAction" />
 		<Class class="CSharpBinding.Refactoring.RenameFileToMatchTypeNameContextAction" />
+		<Class class="CSharpBinding.Refactoring.ParamRangeCheckContextAction" />
 	</Path>
 	
 	<Path name = "/SharpDevelop/Workbench/DisplayBindings">

src/AddIns/BackendBindings/CSharpBinding/Project/CSharpBinding.csproj

@@ -110,6 +110,7 @@
     <Compile Include="Src\Refactoring\IssueOptionsViewModel.cs" />
     <Compile Include="Src\Refactoring\MoveTypeToFileContextAction.cs" />
     <Compile Include="Src\Refactoring\Options.cs" />
+    <Compile Include="Src\Refactoring\ParamRangeCheckContextAction.cs" />
     <Compile Include="Src\Refactoring\RefactoringExtensions.cs" />
     <Compile Include="Src\Refactoring\OverrideEqualsGetHashCodeMethodsDialog.xaml.cs">
       <DependentUpon>OverrideEqualsGetHashCodeMethodsDialog.xaml</DependentUpon>

src/AddIns/BackendBindings/CSharpBinding/Project/Src/Refactoring/ParamRangeCheckContextAction.cs

@@ -0,0 +1,89 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
+// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using ICSharpCode.NRefactory.CSharp;
+using ICSharpCode.NRefactory.CSharp.Refactoring;
+using ICSharpCode.NRefactory.TypeSystem;
+using ICSharpCode.SharpDevelop.Refactoring;
+using CSharpBinding.Parser;
+
+namespace CSharpBinding.Refactoring
+{
+	[ContextAction("Add range check for parameter", Description = "Adds a parameter range check.")]
+	public class ParamRangeCheckContextAction : ContextAction
+	{
+		public override async Task<bool> IsAvailableAsync(EditorRefactoringContext context, System.Threading.CancellationToken cancellationToken)
+		{
+			SyntaxTree st = await context.GetSyntaxTreeAsync().ConfigureAwait(false);
+			Identifier identifier = (Identifier) st.GetNodeAt(context.CaretLocation, node => node.Role == Roles.Identifier);
+			if (identifier == null)
+				return false;
+			ParameterDeclaration parameterDeclaration = identifier.Parent as ParameterDeclaration;
+			if (parameterDeclaration == null)
+				return false;
+			ICompilation compilation = await context.GetCompilationAsync().ConfigureAwait(false);
+			ITypeReference typeRef = parameterDeclaration.Type.ToTypeReference();
+			if (typeRef == null)
+				return false;
+			IType type = typeRef.Resolve(compilation);
+			if (type == null)
+				return false;
+			return type.HasRange();
+		}
+		
+		public override void Execute(EditorRefactoringContext context)
+		{
+			CSharpFullParseInformation parseInformation = context.GetParseInformation() as CSharpFullParseInformation;
+			if (parseInformation != null) {
+				SyntaxTree st = parseInformation.SyntaxTree;
+				Identifier identifier = (Identifier) st.GetNodeAt(context.CaretLocation, node => node.Role == Roles.Identifier);
+				if (identifier == null)
+					return;
+				ParameterDeclaration parameterDeclaration = identifier.Parent as ParameterDeclaration;
+				if (parameterDeclaration == null)
+					return;
+				
+				AstNode grandparent = identifier.Parent.Parent;
+				if ((grandparent is MethodDeclaration) || (grandparent is ConstructorDeclaration)) {
+					// Range check condition
+					var rangeCheck = new IfElseStatement(
+						new BinaryOperatorExpression(
+							new BinaryOperatorExpression(new IdentifierExpression(identifier.Name), BinaryOperatorType.LessThan, new IdentifierExpression("lower")),
+							BinaryOperatorType.ConditionalOr,
+							new BinaryOperatorExpression(new IdentifierExpression(identifier.Name), BinaryOperatorType.GreaterThan, new IdentifierExpression("upper"))
+						),
+						new ThrowStatement(
+							new ObjectCreateExpression(
+								new SimpleType("ArgumentOutOfRangeException"),
+								new List<Expression>() { new PrimitiveExpression(identifier.Name, '"' + identifier.Name + '"'), new IdentifierExpression(identifier.Name), new BinaryOperatorExpression(new PrimitiveExpression("Value must be between "), BinaryOperatorType.Add, new BinaryOperatorExpression(new IdentifierExpression("lower"), BinaryOperatorType.Add, new BinaryOperatorExpression(new PrimitiveExpression(" and "), BinaryOperatorType.Add, new IdentifierExpression("upper")))) }
+							)
+						)
+					);
+					
+					// Add range check as first statement in method's/constructor's body
+					var refactoringContext = SDRefactoringContext.Create(context.Editor, CancellationToken.None);
+					using (Script script = refactoringContext.StartScript()) {
+						if (grandparent is MethodDeclaration) {
+							var methodDeclaration = (MethodDeclaration) grandparent;
+							script.AddTo(methodDeclaration.Body, rangeCheck);
+						} else if (grandparent is ConstructorDeclaration) {
+							var ctorDeclaration = (ConstructorDeclaration) grandparent;
+							script.AddTo(ctorDeclaration.Body, rangeCheck);
+						}
+					}
+				}
+			}
+		}
+		
+		public override string DisplayName {
+			get {
+				return "Add range check for parameter";
+			}
+		}
+	}
+}

src/AddIns/BackendBindings/CSharpBinding/Project/Src/Refactoring/PropertyOrFieldWrapper.cs

@@ -75,16 +75,13 @@ namespace CSharpBinding.Refactoring
 		public bool IsNullable {
 			get {
 				// true = reference, null = generic or unknown
-				return Member.ReturnType.IsReferenceType != false
+				return Member.ReturnType.IsNullable();
-					|| (Member.ReturnType.FullName == "System.Nullable");
 			}
 		}
 		
 		public bool HasRange {
 			get {
-				return IsTypeWithRange(Member.ReturnType) ||
+				return Member.ReturnType.HasRange();
-					(Member.ReturnType.FullName == "System.Nullable")
-					&& IsTypeWithRange(Member.ReturnType.TypeArguments.First());
 			}
 		}
 		
@@ -104,19 +101,6 @@ namespace CSharpBinding.Refactoring
 			}
 		}
 		
-		bool IsTypeWithRange(IType type)
-		{
-			string crtType = type.FullName;
-			return crtType == "System.Int32" ||
-				crtType == "System.Int16" ||
-				crtType == "System.Int64" ||
-				crtType == "System.Single" ||
-				crtType == "System.Double" ||
-				crtType == "System.UInt16" ||
-				crtType == "System.UInt32" ||
-				crtType == "System.UInt64";
-		}
-		
 		static string ToParameterName(string memberName)
 		{
 			if (string.IsNullOrEmpty(memberName))

src/AddIns/BackendBindings/CSharpBinding/Project/Src/Refactoring/RefactoringExtensions.cs

@@ -46,6 +46,43 @@ namespace CSharpBinding.Refactoring
 			return false;
 		}
 		
+		/// <summary>
+		/// Checks whether a type is nullable.
+		/// </summary>
+		/// <param name="type">Checked type</param>
+		/// <returns>True if nullable, false otherwise.</returns>
+		public static bool IsNullable(this IType type)
+		{
+			// true = reference, null = generic or unknown
+			return type.IsReferenceType != false
+				|| (type.FullName == "System.Nullable");
+		}
+		
+		/// <summary>
+		/// Checks whether a type has a range.
+		/// </summary>
+		/// <param name="type">Checked type</param>
+		/// <returns>True if type has range, false otherwise.</returns>
+		public static bool HasRange(this IType type)
+		{
+			return IsTypeWithRange(type) ||
+				(type.FullName == "System.Nullable")
+				&& IsTypeWithRange(type.TypeArguments.First());
+		}
+		
+		static bool IsTypeWithRange(IType type)
+		{
+			string crtType = type.FullName;
+			return crtType == "System.Int32" ||
+				crtType == "System.Int16" ||
+				crtType == "System.Int64" ||
+				crtType == "System.Single" ||
+				crtType == "System.Double" ||
+				crtType == "System.UInt16" ||
+				crtType == "System.UInt32" ||
+				crtType == "System.UInt64";
+		}
+		
 		/// <summary>
 		/// Retrieves the declaration for the specified entity.
 		/// Returns null if the entity is not defined in C# source code.