Fix crash in ConvertIfToSwitchAction when there are nested if statements.

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

@@ -174,22 +174,16 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 		static void CollectSwitchSectionStatements (AstNodeCollection<Statement> result, RefactoringContext context, 
 												    Statement statement)
 		{
-			BlockStatement blockStatement;
-			if (statement is BlockStatement)
-				blockStatement = (BlockStatement)statement.Clone ();
+			BlockStatement blockStatement = statement as BlockStatement;
+			if (blockStatement != null)
+				result.AddRange(blockStatement.Statements.Select(s => s.Clone()));
 			else
-				blockStatement = new BlockStatement { statement.Clone () };
-
-			var breackStatement = new BreakStatement ();
-			blockStatement.Add (breackStatement);
-			// check if break is needed
-			var reachabilityAnalysis = context.CreateReachabilityAnalysis (blockStatement);
-			if (!reachabilityAnalysis.IsReachable (breackStatement))
-				blockStatement.Statements.Remove (breackStatement);
-
-			var statements = blockStatement.Statements.ToArray ();
-			blockStatement.Statements.Clear ();
-			result.AddRange (statements);
+				result.Add(statement.Clone());
+
+			// add 'break;' at end if necessary
+			var reachabilityAnalysis = context.CreateReachabilityAnalysis (statement);
+			if (reachabilityAnalysis.IsEndpointReachable(statement))
+				result.Add(new BreakStatement());
 		}
 	}
 }

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

@@ -30,7 +30,7 @@ using NUnit.Framework;
 namespace ICSharpCode.NRefactory.CSharp.CodeActions
 {
 	[TestFixture]
-	public class ConvertIfToSwtichTests : ContextActionTestBase
+	public class ConvertIfToSwitchTests : ContextActionTestBase
 	{
 
 		[Test]
@@ -467,5 +467,40 @@ class TestClass
 }");
 		}
 	
+		[Test]
+		public void TestNestedIf ()
+		{
+			Test<ConvertIfToSwitchAction> (@"
+class TestClass
+{
+	void TestMethod (int a)
+	{
+		int b;
+		$if (a == 0) {
+			if (b == 0)
+				return;
+		} else if (a == 2 || a == 3) {
+			b = 2;
+		}
+	}
+}", @"
+class TestClass
+{
+	void TestMethod (int a)
+	{
+		int b;
+		switch (a) {
+		case 0:
+			if (b == 0)
+				return;
+			break;
+		case 2:
+		case 3:
+			b = 2;
+			break;
+		}
+	}
+}");
+		}
 	}
 }