Added new code issue to simplify anonymous methods to delegate usages.

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

@@ -513,6 +513,7 @@
     <Compile Include="Resolver\AliasTypeResolveResult.cs" />
     <Compile Include="Resolver\AliasNamespaceResolveResult.cs" />
     <Compile Include="Resolver\ReducedExtensionMethod.cs" />
+    <Compile Include="Refactoring\CodeIssues\SimplifyAnonymousMethodToDelegateIssue.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\ICSharpCode.NRefactory\ICSharpCode.NRefactory.csproj">

ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/SimplifyAnonymousMethodToDelegateIssue.cs

@@ -0,0 +1,116 @@
+//
+// SimplifyAnonymousMethodToDelegateIssue.cs
+//
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+//
+// Copyright (c) 2013 Xamarin Inc. (http://xamarin.com)
+//
+// 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;
+using System.Collections.Generic;
+using System.Linq;
+using ICSharpCode.NRefactory.PatternMatching;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	[IssueDescription("Simplify anonymous method to delegate",
+	                  Description = "Shows anonymous methods that can be simplified.",
+	                  Category = IssueCategories.CodeQualityIssues,
+	                  Severity = Severity.Warning)]
+	public class SimplifyAnonymousMethodToDelegateIssue : ICodeIssueProvider
+	{
+		public IEnumerable<CodeIssue> GetIssues(BaseRefactoringContext context)
+		{
+			return new GatherVisitor(context).GetIssues();
+		}
+
+		class GatherVisitor : GatherVisitorBase
+		{
+			public GatherVisitor (BaseRefactoringContext ctx) : base (ctx)
+			{
+			}
+
+			static Pattern pattern = new Choice {
+				new BlockStatement {
+					new ReturnStatement (new AnyNode ("invoke")) 
+				},
+				new AnyNode ("invoke")
+			};
+
+			static InvocationExpression AnalyzeBody(AstNode body)
+			{
+				var m = pattern.Match(body);
+				if (m.Success)
+					return m.Get("invoke").Single () as InvocationExpression;
+				return null;
+			}
+
+			public override void VisitLambdaExpression(LambdaExpression lambdaExpression)
+			{
+				base.VisitLambdaExpression(lambdaExpression);
+				var invocation = AnalyzeBody(lambdaExpression.Body);
+				if (invocation == null)
+					return;
+
+				var lambdaParameters = lambdaExpression.Parameters.ToList();
+				int i = 0;
+				foreach (var param in invocation.Arguments) {
+					var id = param as IdentifierExpression;
+					if (id == null)
+						return;
+					if (lambdaParameters [i].Name != id.Identifier)
+						return;
+					i++;
+				}
+				
+				AddIssue(
+					lambdaExpression, 
+					ctx.TranslateString("Expression can be reduced to delegate"),
+					script => { script.Replace (lambdaExpression, invocation.Target.Clone ()); });
+			}
+
+			public override void VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression)
+			{
+				base.VisitAnonymousMethodExpression(anonymousMethodExpression);
+
+				var invocation = AnalyzeBody(anonymousMethodExpression.Body);
+				if (invocation == null)
+					return;
+
+				var lambdaParameters = anonymousMethodExpression.Parameters.ToList();
+				int i = 0;
+				foreach (var param in invocation.Arguments) {
+					var id = param as IdentifierExpression;
+					if (id == null)
+						return;
+					if (lambdaParameters [i].Name != id.Identifier)
+						return;
+					i++;
+				}
+				
+				AddIssue(
+					anonymousMethodExpression, 
+					ctx.TranslateString("Expression can be reduced to delegate"),
+					script => { script.Replace (anonymousMethodExpression, invocation.Target.Clone ()); });
+			}
+		}
+	}
+}
+

ICSharpCode.NRefactory.Tests/CSharp/CodeIssues/SimplifyAnonymousMethodToDelegateIssueTests.cs

@@ -0,0 +1,144 @@
+//
+// SimplifyAnonymousMethodToDelegateIssueTests.cs
+//
+// Author:
+//       Mike Krüger <mkrueger@xamarin.com>
+//
+// Copyright (c) 2013 Xamarin Inc. (http://xamarin.com)
+//
+// 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;
+using NUnit.Framework;
+using ICSharpCode.NRefactory.CSharp.Refactoring;
+using ICSharpCode.NRefactory.CSharp.CodeActions;
+
+namespace ICSharpCode.NRefactory.CSharp.CodeIssues
+{
+	[TestFixture]
+	public class SimplifyAnonymousMethodToDelegateIssueTests : InspectionActionTestBase
+	{
+		[Test]
+		public void TestSimpleLambda ()
+		{
+			var input = @"class Foo
+{
+	void Bar (string str)
+	{
+		var action = $(foo, bar) => MyMethod (foo, bar);
+	}
+}";
+			
+			TestRefactoringContext context;
+			var issues = GetIssues (new SimplifyAnonymousMethodToDelegateIssue (), input, out context);
+			Assert.AreEqual (1, issues.Count);
+			CheckFix (context, issues, @"class Foo
+{
+	void Bar (string str)
+	{
+		var action = MyMethod;
+	}
+}");
+		}
+
+		[Test]
+		public void TestLambdaWithBody ()
+		{
+			var input = @"class Foo
+{
+	void Bar (string str)
+	{
+		var action = $(foo, bar) => { return MyMethod (foo, bar); };
+	}
+}";
+			
+			TestRefactoringContext context;
+			var issues = GetIssues (new SimplifyAnonymousMethodToDelegateIssue (), input, out context);
+			Assert.AreEqual (1, issues.Count);
+			CheckFix (context, issues, @"class Foo
+{
+	void Bar (string str)
+	{
+		var action = MyMethod;
+	}
+}");
+		}
+
+		[Test]
+		public void TestSimpleInvalidLambda ()
+		{
+			var input = @"class Foo
+{
+	void Bar (string str)
+	{
+		var action = $(foo, bar) => MyMethod (bar, foo);
+	}
+}";
+			
+			TestRefactoringContext context;
+			var issues = GetIssues (new SimplifyAnonymousMethodToDelegateIssue (), input, out context);
+			Assert.AreEqual (0, issues.Count);
+		}
+
+		[Test]
+		public void TestSimpleAnonymousMethod ()
+		{
+			var input = @"class Foo
+{
+	int MyMethod (int x, int y) { return x * y; }
+
+	void Bar (string str)
+	{
+		var action = $delegate(int foo, int bar) { return MyMethod (foo, bar); };
+	}
+}";
+			
+			TestRefactoringContext context;
+			var issues = GetIssues (new SimplifyAnonymousMethodToDelegateIssue (), input, out context);
+			Assert.AreEqual (1, issues.Count);
+			CheckFix (context, issues, @"class Foo
+{
+	int MyMethod (int x, int y) { return x * y; }
+
+	void Bar (string str)
+	{
+		var action = MyMethod;
+	}
+}");
+		}
+
+		[Test]
+		public void TestSimpleInvalidAnonymousMethod ()
+		{
+			var input = @"class Foo
+{
+	int MyMethod (int x, int y) { return x * y; }
+
+	void Bar (string str)
+	{
+		var action = $delegate(int foo, int bar) { return MyMethod (bar, foo); };
+	}
+}";
+			
+			TestRefactoringContext context;
+			var issues = GetIssues (new SimplifyAnonymousMethodToDelegateIssue (), input, out context);
+			Assert.AreEqual (0, issues.Count);
+		}
+	}
+}
+

ICSharpCode.NRefactory.Tests/ICSharpCode.NRefactory.Tests.csproj

@@ -391,6 +391,7 @@
     <Compile Include="CSharp\CodeCompletion\ImportCompletionTests.cs" />
     <Compile Include="CSharp\CodeActions\CreateEnumValueTests.cs" />
     <Compile Include="CSharp\CodeCompletion\GetCurrentParameterIndexTests.cs" />
+    <Compile Include="CSharp\CodeIssues\SimplifyAnonymousMethodToDelegateIssueTests.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\cecil\Mono.Cecil.csproj">