diff --git a/ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj b/ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj
index acb5d47920..be84017aa7 100644
--- a/ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj
+++ b/ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj
@@ -294,6 +294,7 @@
+
diff --git a/ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/MethodOverloadHidesOptionalParameterIssue.cs b/ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/MethodOverloadHidesOptionalParameterIssue.cs
new file mode 100644
index 0000000000..ebdef9abf3
--- /dev/null
+++ b/ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/MethodOverloadHidesOptionalParameterIssue.cs
@@ -0,0 +1,84 @@
+//
+// MethodOverloadHidesOptionalParameterIssue.cs
+//
+// Author:
+// Mansheng Yang
+//
+// Copyright (c) 2012 Mansheng Yang
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using System.Collections.Generic;
+using System.Linq;
+using ICSharpCode.NRefactory.Semantics;
+using ICSharpCode.NRefactory.TypeSystem;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring.CodeIssues
+{
+ [IssueDescription ("Method with optional parameter is hidden by overload",
+ Description = "Method with optional parameter is hidden by overload",
+ Category = IssueCategories.CodeQualityIssues,
+ Severity = Severity.Warning,
+ IssueMarker = IssueMarker.Underline)]
+ public class MethodOverloadHidesOptionalParameterIssue : ICodeIssueProvider
+ {
+ public IEnumerable GetIssues (BaseRefactoringContext context)
+ {
+ return new GatherVisitor (context).GetIssues ();
+ }
+
+ class GatherVisitor : GatherVisitorBase
+ {
+ public GatherVisitor(BaseRefactoringContext ctx)
+ : base (ctx)
+ {
+ }
+
+ public override void VisitMethodDeclaration (MethodDeclaration methodDeclaration)
+ {
+ base.VisitMethodDeclaration (methodDeclaration);
+
+ var resolveResult = ctx.Resolve (methodDeclaration) as MemberResolveResult;
+ if (resolveResult == null)
+ return;
+ var method = resolveResult.Member as IMethod;
+ if (method == null)
+ return;
+
+ if (method.Parameters.Count == 0 || !method.Parameters.Last ().IsOptional)
+ return;
+
+ var overloads = method.DeclaringType.GetMembers (m => m.Name == method.Name).OfType ()
+ .ToArray ();
+
+ var parameterNodes = methodDeclaration.Parameters.ToArray();
+ var parameters = new List ();
+ for (int i = 0; i < method.Parameters.Count; i++) {
+ if (method.Parameters [i].IsOptional &&
+ overloads.Any (m => ParameterListComparer.Instance.Equals (parameters, m.Parameters))) {
+ AddIssue (parameterNodes [i].StartLocation, parameterNodes.Last ().EndLocation,
+ ctx.TranslateString ("Method with optional parameter is hidden by overload"));
+ break;
+ }
+ parameters.Add (method.Parameters [i]);
+ }
+ }
+ }
+ }
+}
diff --git a/ICSharpCode.NRefactory.Tests/CSharp/CodeIssues/MethodOverloadHidesOptionalParameterIssueTests.cs b/ICSharpCode.NRefactory.Tests/CSharp/CodeIssues/MethodOverloadHidesOptionalParameterIssueTests.cs
new file mode 100644
index 0000000000..24c6614068
--- /dev/null
+++ b/ICSharpCode.NRefactory.Tests/CSharp/CodeIssues/MethodOverloadHidesOptionalParameterIssueTests.cs
@@ -0,0 +1,75 @@
+//
+// MethodOverloadHidesOptionalParameterIssueTests.cs
+//
+// Author:
+// Mansheng Yang
+//
+// Copyright (c) 2012 Mansheng Yang
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using ICSharpCode.NRefactory.CSharp.Refactoring.CodeIssues;
+using NUnit.Framework;
+
+namespace ICSharpCode.NRefactory.CSharp.CodeIssues
+{
+ [TestFixture]
+ public class MethodOverloadHidesOptionalParameterIssueTests : InspectionActionTestBase
+ {
+ [Test]
+ public void Test ()
+ {
+ var input = @"
+class TestClass
+{
+ void TestMethod (int a)
+ { }
+ void TestMethod (int a, int b = 1)
+ { }
+}";
+ Test (input, 1);
+ }
+
+ [Test]
+ public void Test2 ()
+ {
+ var input = @"
+class TestClass
+{
+ void TestMethod (int a, int b)
+ { }
+ void TestMethod (int a, int b = 1, int c = 1)
+ { }
+}";
+ Test (input, 1);
+ }
+
+ [Test]
+ public void TestNoIssue ()
+ {
+ var input = @"
+class TestClass
+{
+ void TestMethod (int a, int b = 1, int c = 1)
+ { }
+}";
+ Test (input, 0);
+ }
+ }
+}
diff --git a/ICSharpCode.NRefactory.Tests/ICSharpCode.NRefactory.Tests.csproj b/ICSharpCode.NRefactory.Tests/ICSharpCode.NRefactory.Tests.csproj
index e0849588c8..3d9ef01c62 100644
--- a/ICSharpCode.NRefactory.Tests/ICSharpCode.NRefactory.Tests.csproj
+++ b/ICSharpCode.NRefactory.Tests/ICSharpCode.NRefactory.Tests.csproj
@@ -111,6 +111,7 @@
+