[CodeAction] Added MergeNestedIfAction

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

@@ -247,6 +247,7 @@
     <Compile Include="Refactoring\CodeActions\ConvertSwitchToIfAction.cs" />
     <Compile Include="Refactoring\CodeActions\CreateCustomEventImplementationAction.cs" />
     <Compile Include="Refactoring\CodeActions\CreateOverloadWithoutParameterAction.cs" />
+    <Compile Include="Refactoring\CodeActions\MergeNestedIfAction.cs" />
     <Compile Include="Refactoring\CodeActions\SplitDeclarationListAction.cs" />
     <Compile Include="Refactoring\CodeIssues\ExplicitConversionInForEachIssue.cs" />
     <Compile Include="Refactoring\DocumentScript.cs" />

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

@@ -0,0 +1,106 @@
+// 
+// MergeNestedIfAction.cs
+//  
+// Author:
+//       Mansheng Yang <lightyang0@gmail.com>
+// 
+// Copyright (c) 2012 Mansheng Yang <lightyang0@gmail.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.Linq;
+
+namespace ICSharpCode.NRefactory.CSharp.Refactoring
+{
+	[ContextAction ("Merge nested 'if'", Description = "Merge two nested 'if' statements.")]
+	public class MergeNestedIfAction : SpecializedCodeAction<IfElseStatement>
+	{
+		static readonly InsertParenthesesVisitor insertParenthesesVisitor = new InsertParenthesesVisitor ();
+
+		protected override CodeAction GetAction (RefactoringContext context, IfElseStatement node)
+		{
+			if (!node.Contains (context.Location))
+				return null;
+
+			IfElseStatement outerIfStatement;
+			IfElseStatement innerIfStatement = GetInnerIfStatement (node);
+			if (innerIfStatement != null) {
+				if (!innerIfStatement.FalseStatement.IsNull)
+					return null;
+				outerIfStatement = node;
+			} else {
+				outerIfStatement = GetOuterIfStatement (node);
+				if (outerIfStatement == null || !outerIfStatement.FalseStatement.IsNull)
+					return null;
+				innerIfStatement = node;
+			}
+
+			return new CodeAction (context.TranslateString ("Merge nested 'if's"),
+				script =>
+				{
+					var mergedIfStatement = new IfElseStatement
+					{
+						Condition = new BinaryOperatorExpression (outerIfStatement.Condition.Clone (),
+																  BinaryOperatorType.ConditionalAnd, 
+																  innerIfStatement.Condition.Clone ()),
+						TrueStatement = innerIfStatement.TrueStatement.Clone ()
+					};
+					mergedIfStatement.Condition.AcceptVisitor (insertParenthesesVisitor);
+					script.Replace (outerIfStatement, mergedIfStatement);
+				});
+		}
+
+		static IfElseStatement GetOuterIfStatement (IfElseStatement node)
+		{
+			var outerIf = node.Parent as IfElseStatement;
+			if (outerIf != null)
+				return outerIf;
+
+			var blockStatement = node.Parent as BlockStatement;
+			while (blockStatement != null && blockStatement.Statements.Count == 1) {
+				outerIf = blockStatement.Parent as IfElseStatement;
+				if (outerIf != null)
+					return outerIf;
+				blockStatement = blockStatement.Parent as BlockStatement;
+			}
+
+			return null;
+		}
+
+		static IfElseStatement GetInnerIfStatement (IfElseStatement node)
+		{
+			if (!node.FalseStatement.IsNull)
+				return null;
+
+			var innerIf = node.TrueStatement as IfElseStatement;
+			if (innerIf != null)
+				return innerIf;
+
+			var blockStatement = node.TrueStatement as BlockStatement;
+			while (blockStatement != null && blockStatement.Statements.Count == 1) {
+				innerIf = blockStatement.Statements.First () as IfElseStatement;
+				if (innerIf != null)
+					return innerIf;
+				blockStatement = blockStatement.Statements.First () as BlockStatement;
+			}
+
+			return null;
+		}
+	}
+}

ICSharpCode.NRefactory.Tests/CSharp/CodeActions/MergeNestedIfTests.cs

@@ -0,0 +1,226 @@
+// 
+// MergeNestedIfTests.cs
+//  
+// Author:
+//       Mansheng Yang <lightyang0@gmail.com>
+// 
+// Copyright (c) 2012 Mansheng Yang <lightyang0@gmail.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 ICSharpCode.NRefactory.CSharp.Refactoring;
+using NUnit.Framework;
+
+namespace ICSharpCode.NRefactory.CSharp.CodeActions
+{
+	[TestFixture]
+	public class MergeNestedIfTests : ContextActionTestBase
+	{
+		[Test]
+		public void TestOuterIf ()
+		{
+			Test<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0)
+			if (a < 5) 
+				return 1;
+	}
+}", @"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0 && a < 5)
+			return 1;
+	}
+}");
+		}
+
+		[Test]
+		public void TestOuterIfWithBlock ()
+		{
+			Test<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0) {
+
+		{
+			if (a < 5) 
+				return 1;
+		}
+
+		}
+	}
+}", @"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0 && a < 5)
+			return 1;
+	}
+}");
+		}
+
+		[Test]
+		public void TestInnerIf ()
+		{
+			Test<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0)
+			$if (a < 5) 
+				return 1;
+	}
+}", @"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0 && a < 5)
+			return 1;
+	}
+}");
+		}
+
+		[Test]
+		public void TestInnerIfWithBlock ()
+		{
+			Test<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0) {
+
+		{
+			$if (a < 5) 
+				return 1;
+		}
+
+		}
+	}
+}", @"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0 && a < 5)
+			return 1;
+	}
+}");
+		}
+		
+		[Test]
+		public void TestOuterIfElse ()
+		{
+			TestWrongContext<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0)
+			if (a < 5) 
+				return 1;
+		else
+			return 0;
+	}
+}");
+			TestWrongContext<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0) {
+			if (a < 5) 
+				return 1;
+		} else
+			return 0;
+	}
+}");
+		}
+		
+		[Test]
+		public void TestInnerIfElse ()
+		{
+			TestWrongContext<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0)
+			if (a < 5) 
+				return 1;
+			else
+				return 0;
+	}
+}");
+			TestWrongContext<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0) {
+			if (a < 5) 
+				return 1;
+			else
+				return 0;
+		}
+	}
+}");
+		}
+		
+		[Test]
+		public void TestMultipleTrueStatements ()
+		{
+			TestWrongContext<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		$if (a > 0) {
+			if (a < 5) 
+				return 1;
+			return 0;
+		}
+	}
+}");
+			TestWrongContext<MergeNestedIfAction> (@"
+class TestClass
+{
+	int TestMethod (int a)
+	{
+		if (a > 0) {
+			$if (a < 5) 
+				return 1;
+			return 0;
+		}
+	}
+}");
+		}
+	}
+}

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

@@ -87,6 +87,7 @@
     <Compile Include="CSharp\CodeActions\ConvertSwitchToIfTests.cs" />
     <Compile Include="CSharp\CodeActions\CreateCustomEventImplementationTests.cs" />
     <Compile Include="CSharp\CodeActions\CreateOverloadWithoutParameterTests.cs" />
+    <Compile Include="CSharp\CodeActions\MergeNestedIfTests.cs" />
     <Compile Include="CSharp\CodeActions\SplitDeclarationListTests.cs" />
     <Compile Include="CSharp\CodeIssues\ExplicitConversionInForEachIssueTests.cs" />
     <Compile Include="CSharp\CSharpAmbienceTests.cs" />