Simplify the transform code by using extension methods.

Decompiler.csproj

@@ -1,4 +1,4 @@
-<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="3.5">
   <PropertyGroup>
     <ProjectGuid>{EE3A3C1A-F9C3-4C75-853D-A9476E518C3A}</ProjectGuid>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
@@ -6,6 +6,7 @@
     <OutputType>WinExe</OutputType>
     <RootNamespace>Decompiler</RootNamespace>
     <AssemblyName>Decompiler</AssemblyName>
+    <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
     <OutputPath>bin\Debug\</OutputPath>
@@ -26,10 +27,19 @@
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.Targets" />
   <ItemGroup>
     <Reference Include="System" />
+    <Reference Include="System.Core">
+      <RequiredTargetFramework>3.5</RequiredTargetFramework>
+    </Reference>
     <Reference Include="System.Data" />
+    <Reference Include="System.Data.DataSetExtensions">
+      <RequiredTargetFramework>3.5</RequiredTargetFramework>
+    </Reference>
     <Reference Include="System.Drawing" />
     <Reference Include="System.Windows.Forms" />
     <Reference Include="System.Xml" />
+    <Reference Include="System.Xml.Linq">
+      <RequiredTargetFramework>3.5</RequiredTargetFramework>
+    </Reference>
   </ItemGroup>
   <ItemGroup>
     <Folder Include="src" />

lib/NRefactory/Project/NRefactory.csproj

@@ -23,7 +23,7 @@
     <FileAlignment>4096</FileAlignment>
     <RunCodeAnalysis>False</RunCodeAnalysis>
     <CodeAnalysisRules>-Microsoft.Design#CA1002;-Microsoft.Design#CA1020;-Microsoft.Design#CA1051;-Microsoft.Design#CA1062;-Microsoft.Globalization#CA1303;-Microsoft.Globalization#CA1305;-Microsoft.Naming#CA1704;-Microsoft.Performance#CA1800;-Microsoft.Performance#CA1805;-Microsoft.Usage#CA2211;-Microsoft.Usage#CA2227</CodeAnalysisRules>
-    <TargetFrameworkVersion>v2.0</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <Optimize>False</Optimize>
@@ -49,6 +49,9 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
+    <Reference Include="System.Core">
+      <RequiredTargetFramework>3.5</RequiredTargetFramework>
+    </Reference>
   </ItemGroup>
   <ItemGroup>
     <None Include="Resources\ICSharpCode.NRefactory.snk" />

lib/NRefactory/Project/Src/Ast/INode.cs

@@ -52,4 +52,42 @@ namespace ICSharpCode.NRefactory.Ast
 		/// <returns>The value the visitor returns after the visit</returns>
 		object AcceptVisitor(IAstVisitor visitor, object data);
 	}
+	
+	public static class INodeExtensionMethods
+	{
+		public static void Remove(this INode node)
+		{
+			node.Parent.Children.Remove(node);
+		}
+		
+		public static INode Previous(this INode node)
+		{
+			if (node.Parent == null) return null;
+			int myIndex = node.Parent.Children.IndexOf(node);
+			int index = myIndex - 1;
+			if (0 <= index && index < node.Parent.Children.Count) {
+				return node.Parent.Children[index];
+			} else {
+				return null;
+			}
+		}
+		
+		public static INode Next(this INode node)
+		{
+			if (node.Parent == null) return null;
+			int myIndex = node.Parent.Children.IndexOf(node);
+			int index = myIndex + 1;
+			if (0 <= index && index < node.Parent.Children.Count) {
+				return node.Parent.Children[index];
+			} else {
+				return null;
+			}
+		}
+		
+		public static void ReplaceWith(this INode node, INode newNode)
+		{
+			int myIndex = node.Parent.Children.IndexOf(node);
+			node.Parent.Children[myIndex] = newNode;
+		}
+	}
 }

src/Transforms/Ast/RemoveGotos.cs

@@ -12,19 +12,19 @@ namespace Decompiler.Transforms.Ast
 			base.VisitBlockStatement(blockStatement, data);
 			
 			// Remove redundant jump at the end of block
-			INode lastStmt = blockStatement.Children[blockStatement.Children.Count - 1];
+			INode lastStmt = blockStatement.Children.Last;
 			// End of while loop
 			if (lastStmt is ContinueStatement && 
 			    blockStatement.Parent is DoLoopStatement)
 			{
-				blockStatement.Children.Remove(lastStmt);
+				lastStmt.Remove();
 				return null;
 			}
 			// End of for loop
 			if (lastStmt is ContinueStatement && 
 			    blockStatement.Parent is ForStatement)
 			{
-				blockStatement.Children.Remove(lastStmt);
+				lastStmt.Remove();
 				return null;
 			}
 			// End of method
@@ -32,21 +32,19 @@ namespace Decompiler.Transforms.Ast
 			    blockStatement.Parent is MethodDeclaration &&
 			    ((ReturnStatement)lastStmt).Expression.IsNull)
 			{
-				blockStatement.Children.Remove(lastStmt);
+				lastStmt.Remove();
 				return null;
 			}
 			// End of if body
 			if (lastStmt is GotoStatement &&
 			    blockStatement.Parent is IfElseStatement)
 			{
-				INode ifParent = blockStatement.Parent.Parent;
+				MyLabelStatement nextNodeAsLabel = blockStatement.Parent.Next() as MyLabelStatement;
-				int ifIndex = ifParent.Children.IndexOf(blockStatement.Parent);
-				if (ifIndex + 1 < ifParent.Children.Count) {
-					MyLabelStatement nextNodeAsLabel = ifParent.Children[ifIndex + 1] as MyLabelStatement;
 				if (nextNodeAsLabel != null) {
 					if (nextNodeAsLabel.NodeLabel == ((MyGotoStatement)lastStmt).NodeLabel) {
 						((MyGotoStatement)lastStmt).NodeLabel.ReferenceCount--;
-							blockStatement.Children.Remove(lastStmt);
+						lastStmt.Remove();
+						return null;
 					}
 				}
 			}
@@ -54,22 +52,14 @@ namespace Decompiler.Transforms.Ast
 			return null;
 		}
 		
-			return null;
-		}
-		
 		public override object VisitGotoStatement(GotoStatement gotoStatement, object data)
 		{
 			MyGotoStatement myGoto = (MyGotoStatement)gotoStatement;
-			if (gotoStatement.Parent == null) return null;
+			MyLabelStatement followingLabel = myGoto.Next() as MyLabelStatement;
-			int index = gotoStatement.Parent.Children.IndexOf(gotoStatement);
+			if (followingLabel != null && followingLabel.NodeLabel == myGoto.NodeLabel) {
-			if (index + 1 < gotoStatement.Parent.Children.Count) {
-				INode nextStmt = gotoStatement.Parent.Children[index + 1];
-				MyLabelStatement myLabel = nextStmt as MyLabelStatement;
-				if (myLabel != null && myLabel.NodeLabel == myGoto.NodeLabel) {
 				myGoto.NodeLabel.ReferenceCount--;
 				RemoveCurrentNode();
 			}
-			}
 			return null;
 		}
 	}

src/Transforms/Ast/RestoreLoop.cs

@@ -14,15 +14,12 @@ namespace Decompiler.Transforms.Ast
 			
 			// Restore loop initializer
 			if (forStatement.Initializers.Count == 0) {
-				int myIndex = forStatement.Parent.Children.IndexOf(forStatement);
+				LocalVariableDeclaration varDeclr = forStatement.Previous() as LocalVariableDeclaration;
-				if (myIndex - 1 >= 0) {
-					LocalVariableDeclaration varDeclr = forStatement.Parent.Children[myIndex - 1] as LocalVariableDeclaration;
 				if (varDeclr != null) {
-						forStatement.Parent.Children[myIndex - 1] = Statement.Null;
+					varDeclr.ReplaceWith(Statement.Null);
 					forStatement.Initializers.Add(varDeclr);
 				}
 			}
-			}
 			
 			// Restore loop condition
 			if (forStatement.Condition.IsNull &&
@@ -31,15 +28,13 @@ namespace Decompiler.Transforms.Ast
 				IfElseStatement  condition = forStatement.EmbeddedStatement.Children[0] as IfElseStatement;
 				BreakStatement   breakStmt = forStatement.EmbeddedStatement.Children[1] as BreakStatement;
 				MyLabelStatement label     = forStatement.EmbeddedStatement.Children[2] as MyLabelStatement;
-				if (condition != null &&
+				if (condition != null && breakStmt != null && label != null &&
-				    breakStmt != null &&
-				    label != null &&
 				    condition.TrueStatement.Count == 1)
 				{
 					MyGotoStatement gotoStmt = condition.TrueStatement[0] as MyGotoStatement;
 					if (gotoStmt != null && gotoStmt.NodeLabel == label.NodeLabel) {
-						forStatement.EmbeddedStatement.Children.Remove(condition);
+						condition.Remove();
-						forStatement.EmbeddedStatement.Children.Remove(breakStmt);
+						breakStmt.Remove();
 						gotoStmt.NodeLabel.ReferenceCount--;
 						forStatement.Condition = condition.Condition;
 					}
@@ -54,7 +49,7 @@ namespace Decompiler.Transforms.Ast
 				if (lastStmt != null) {
 					AssignmentExpression assign = lastStmt.Expression as AssignmentExpression;
 					if (assign != null) {
-						forStatement.EmbeddedStatement.Children.Remove(lastStmt);
+						lastStmt.Remove();
 						forStatement.Iterator.Add(lastStmt);
 					}
 				}