Redundant block in branches

ICSharpCode.NRefactory.CSharp.Refactoring/CodeIssues/Uncategorized/RedundantBlockInDifferentBranchesIssue.cs

@@ -0,0 +1,84 @@
+// RedundantBlockInDifferentBranchesIssue.cs
+//
+// Author:
+//      Ji Kun <[email protected]>
+// 
+// Copyright (c) 2013 Ji Kun <[email protected]>
+// 
+// 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.Semantics;
+using ICSharpCode.NRefactory.TypeSystem;
+using ICSharpCode.NRefactory.PatternMatching;
+using ICSharpCode.NRefactory.Refactoring;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	[IssueDescription("RedundantBlockInDifferentBranches",
+						Description = "Blocks in if/else can be simplified to any of the branches if they have the same block.",
+						Category = IssueCategories.RedundanciesInCode,
+						Severity = Severity.Hint,
+						ResharperDisableKeyword = "RedundantBlockInDifferentBranches",
+						IssueMarker = IssueMarker.WavedLine)]
+	public class RedundantBlockInDifferentBranchesIssue : GatherVisitorCodeIssueProvider
+	{
+
+		protected override IGatherVisitor CreateVisitor(BaseRefactoringContext context)
+		{
+			return new GatherVisitor(context, this);
+		}
+
+		class GatherVisitor : GatherVisitorBase<RedundantBlockInDifferentBranchesIssue>
+		{
+			public GatherVisitor(BaseRefactoringContext ctx, RedundantBlockInDifferentBranchesIssue issueProvider) : base (ctx, issueProvider)
+			{
+			}
+
+			static readonly AstNode pattern = new Choice{
+				new IfElseStatement(
+					new AnyNode("c"), 
+					new AnyNode("s"), 
+					new BlockStatement{new Backreference("s")}),
+				new IfElseStatement(
+					new AnyNode("c"), 
+					new AnyNode("s"), 
+					new Backreference("s")),
+				new IfElseStatement(
+					new AnyNode("c"), 
+					new BlockStatement{new AnyNode("s")}, 
+					new Backreference("s"))
+			};
+
+			public override void VisitIfElseStatement(IfElseStatement ifElseStatement)
+			{
+				base.VisitIfElseStatement(ifElseStatement);
+				var m = pattern.Match(ifElseStatement);
+
+				if (!m.Success)
+					return;
+
+				AddIssue(ifElseStatement.ElseToken, ctx.TranslateString("Blocks in if/else or switch branches can be simplified to any of the branches if they have the same block."), ctx.TranslateString("Change if/else statement to statements"), 
+						script =>
+				{
+					IfElseStatement newStatement = new IfElseStatement(ifElseStatement.Condition.Clone(), ifElseStatement.TrueStatement.Clone());
+					script.Replace(ifElseStatement, newStatement);	
+				});
+			}
+		}
+	}
+}

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

@@ -395,6 +395,7 @@
     <Compile Include="CodeIssues\Synced\RedundanciesInCode\RedundantLogicalConditionalExpressionOperandIssue.cs" />
     <Compile Include="CodeIssues\Synced\RedundanciesInCode\ForStatementConditionIsTrueIssue.cs" />
     <Compile Include="CodeIssues\Synced\Opportunities\ConvertToStaticTypeIssue.cs" />
+    <Compile Include="CodeIssues\Uncategorized\RedundantBlockInDifferentBranchesIssue.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <ItemGroup>

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

@@ -0,0 +1,163 @@
+using ICSharpCode.NRefactory.CSharp.Refactoring;
+using NUnit.Framework;
+
+namespace ICSharpCode.NRefactory.CSharp.CodeIssues
+{
+	[TestFixture]
+	public class RedundantBlockInDifferentBranchesTests : InspectionActionTestBase
+	{
+		[Test]
+		public void TestConditionalExpression1()
+		{
+			var input = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+		{
+			foo = foo +  1;
+			foo = foo + foo;
+		}
+		else
+		{
+			foo = foo + 1;
+			foo = foo + foo;
+		}
+	}
+}";
+			var output = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5) {
+			foo = foo + 1;
+			foo = foo + foo;
+		}
+	}
+}";
+			Test<RedundantBlockInDifferentBranchesIssue>(input, 1, output);
+		}
+
+		[Test]
+		public void TestConditionalExpression2()
+		{
+			var input = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+			foo = foo + 1;
+		else
+			foo = foo + 1;
+	}
+}";
+			var output = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+			foo = foo + 1;
+	}
+}";
+			Test<RedundantBlockInDifferentBranchesIssue>(input, 1, output);
+		}
+
+		[Test]
+		public void TestConditionalExpression3()
+		{
+			var input = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+			foo = foo + 1;
+		else
+		{
+			foo = foo + 1;
+		}
+	}
+}";
+			var output = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+			foo = foo + 1;
+	}
+}";
+			Test<RedundantBlockInDifferentBranchesIssue>(input, 1, output);
+		}
+
+		[Test]
+		public void TestConditionalExpression4()
+		{
+			var input = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+		{
+		}
+		else
+		{}
+	}
+}";
+			var output = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5) {
+		}
+	}
+}";
+			Test<RedundantBlockInDifferentBranchesIssue>(input, 1 , output);
+		}
+
+		[Test]
+		public void TestNoProblem2()
+		{
+			var input = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+		if (foo > 5)
+		{
+			foo = foo + 1;
+			return 2;
+		}
+		else
+			return 5;
+	}
+}";
+			Test<RedundantBlockInDifferentBranchesIssue>(input, 0);
+		}
+
+		[Test]
+		public void TestResharperDisableRestore()
+		{
+			var input = @"
+class TestClass
+{
+	void TestMethod (int foo)
+	{
+//Resharper disable RedundantBlockInDifferentBranches
+		if (foo > 5)
+			return 2;
+		else
+			return 5;
+//Resharper restore RedundantBlockInDifferentBranches
+	}
+}";
+			Test<RedundantBlockInDifferentBranchesIssue>(input, 0);
+		}
+	}
+}

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

@@ -566,6 +566,7 @@
     <Compile Include="CSharp\CodeActions\SplitIfActionTests.cs" />
     <Compile Include="CSharp\CodeIssues\RedundantLogicalConditionalExpressionOperandIssueTests.cs" />
     <Compile Include="CSharp\CodeIssues\ConvertToStaticTypeTests.cs" />
+    <Compile Include="CSharp\CodeIssues\RedundantBlockInDifferentBranchesTests.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\cecil\Mono.Cecil.csproj">