Fix ArgumentException in StatementsToInitializerConverter.

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/ConvertToInitializer/ConvertToInitializerAction.cs

@@ -60,7 +60,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 			IList<AstNode> statements = GetNodes(context.GetNode<Statement>());
 			var converter = new StatementsToInitializerConverter(context);
 			var newInitializer = converter.ConvertToInitializer(initializer, ref statements);
-			if (statements.Count == 0)
+			if (newInitializer == null || statements.Count == 0)
 				return null;
 			return MakeAction(context, initializer, newInitializer, statements);
 		}
@@ -68,7 +68,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 		CodeAction HandleExpressionStatement(RefactoringContext context, ExpressionStatement expressionStatement)
 		{
 			var expression = expressionStatement.Expression as AssignmentExpression;
-			if (expression == null)
+			if (expression == null || expression.Operator != AssignmentOperatorType.Assign)
 				return null;
 			if (!(expression.Right is ObjectCreateExpression))
 				return null;
@@ -78,7 +78,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 			IList<AstNode> statements = GetNodes(context.GetNode<Statement>());
 			var converter = new StatementsToInitializerConverter(context);
 			var newExpression = converter.ConvertToInitializer(expression, ref statements);
-			if (statements.Count == 0)
+			if (newExpression == null || statements.Count == 0)
 				return null;
 			return MakeAction(context, expression, newExpression, statements);
 		}

ICSharpCode.NRefactory.CSharp/Refactoring/CodeActions/ConvertToInitializer/StatementsToInitializerConverter.cs

@@ -47,14 +47,15 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 			this.context = context;
 		}
 
-		void Initialize(AstNode targetNode)
+		bool Initialize(AstNode targetNode)
 		{
 			var target = context.Resolve(targetNode);
 			var targetInitializerPath = AccessPath.FromResolveResult(target);
 			if (targetInitializerPath == null)
-				throw new ArgumentException(string.Format("Could not create the main initializer path from resolve result ({0})", target));
+				return false;
 
 			mainAccessPath = targetInitializerPath;
+			return true;
 		}
 
 		public VariableInitializer ConvertToInitializer(VariableInitializer variableInitializer, ref IList<AstNode> statements)
@@ -64,7 +65,8 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 			if (statements == null)
 				throw new ArgumentNullException("statements");
 
-			Initialize(variableInitializer);
+			if (!Initialize(variableInitializer))
+				return null;
 			accessPaths [mainAccessPath] = variableInitializer.Initializer.Clone();
 
 			Convert(statements);
@@ -81,7 +83,8 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 			if (!(assignmentExpression.Right is ObjectCreateExpression))
 				throw new ArgumentException("assignmentExpression.Right must be an ObjectCreateExpression", "assignmentExpression");
 
-			Initialize(assignmentExpression.Left);
+			if (!Initialize(assignmentExpression.Left))
+				return null;
 			accessPaths [mainAccessPath] = assignmentExpression.Right.Clone();
 
 			Convert(statements);
@@ -178,7 +181,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 		bool TryHandleAssignmentExpression(ExpressionStatement expressionStatement)
 		{
 			var assignmentExpression = expressionStatement.Expression as AssignmentExpression;
-			if (assignmentExpression == null)
+			if (assignmentExpression == null || assignmentExpression.Operator != AssignmentOperatorType.Assign)
 				return false;
 			var resolveResult = context.Resolve(assignmentExpression.Right);
 			if (HasDependency(assignmentExpression.Right) && !CanReplaceDependent(resolveResult))

ICSharpCode.NRefactory.Tests/CSharp/CodeActions/ConvertToInitializer/ConvertToInitializerTests.cs

@@ -35,7 +35,7 @@ namespace ICSharpCode.NRefactory.CSharp.CodeActions
 	{
 		// TODO: Remove this when the formatter handles object and collection initializers
 		// This tests the expected code vs the actual code based on their ASTs instead of the text they produce.
-		public new void Test<T>(string input, string output, int action = 0, bool expectErrors = false) 
+		public new void Test<T>(string input, string output, int action = 0, bool expectErrors = false)
 			where T : ICodeActionProvider, new ()
 		{
 			string result = RunContextAction(new T(), HomogenizeEol(input), action, expectErrors);
@@ -678,6 +678,27 @@ class TestClass
 	}
 }");
 		}
+		
+		[Test]
+		public void DoesNotCrashOnDelegateAssignment()
+		{
+			TestWrongContext<ConvertToInitializerAction>(@"
+using System;
+using System.Collections.Generic;
+class TestClass {
+	void F() {
+		((CheckBox)ControlDictionary[""ReplaceCheckBox""]).CheckedChanged = new E$ventHandler(ReplaceCheckBox_CheckedChanged);
+	}
+	Dictionary<string, Control> ControlDictionary;
+	void ReplaceCheckBox_CheckedChanged(object sender, EventArgs e) {}
+}
+class Control {}
+class CheckBox : Control {
+	public EventHandler CheckedChanged;
+}
+");
+			
+		}
 	}
 }