AddAnotherAccessorAction: don't try to assign to readonly fields

ICSharpCode.NRefactory.CSharp/OutputVisitor/CodeDomConvertVisitor.cs

@@ -1356,7 +1356,7 @@ namespace ICSharpCode.NRefactory.CSharp
 
 		CodeObject IAstVisitor<CodeObject>.VisitPreProcessorDirective (PreProcessorDirective preProcessorDirective)
 		{
-			return new CodeComment ("#" + preProcessorDirective.Type.ToString ().ToLower ());
+			return new CodeComment ("#" + preProcessorDirective.Type.ToString ().ToLowerInvariant ());
 		}
 		
 		CodeObject IAstVisitor<CodeObject>.VisitTypeParameterDeclaration(TypeParameterDeclaration typeParameterDeclaration)

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

@@ -73,7 +73,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 		{
 			if (pdecl.Setter.IsNull && !pdecl.Getter.IsNull) {
 				var field = RemoveBackingStoreAction.ScanGetter (context, pdecl);
-				if (field != null) 
+				if (field != null && !field.IsReadOnly && !field.IsConst) 
 					return new ExpressionStatement (new AssignmentExpression (new IdentifierExpression (field.Name), AssignmentOperatorType.Assign, new IdentifierExpression ("value")));
 			}
 			

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

@@ -89,7 +89,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 			var setterField = ScanSetter (context, propertyDeclaration);
 			if (setterField == null)
 				return null;
-			if (getterField.Region != setterField.Region)
+			if (!getterField.Equals(setterField))
 				return null;
 			return getterField;
 		}

ICSharpCode.NRefactory.CSharp/Refactoring/CodeIssues/ConstantConditionIssue.cs

@@ -95,7 +95,7 @@ namespace ICSharpCode.NRefactory.CSharp.Refactoring
 				var value = (bool)resolveResult.ConstantValue;
 				var conditionalExpr = condition.Parent as ConditionalExpression;
 				var ifElseStatement = condition.Parent as IfElseStatement;
-				var valueStr = value.ToString ().ToLower ();
+				var valueStr = value.ToString ().ToLowerInvariant ();
 
 				CodeAction action;
 				if (conditionalExpr != null) {

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

@@ -64,6 +64,37 @@ namespace ICSharpCode.NRefactory.CSharp.CodeActions
 				"}", result);
 		}
 		
+		[Test]
+		public void TestAddSet_ReadOnlyField ()
+		{
+			string result = RunContextAction (
+				new AddAnotherAccessorAction (),
+				"class TestClass" + Environment.NewLine +
+				"{" + Environment.NewLine +
+				"	readonly int field;" + Environment.NewLine +
+				"	public int $Field {" + Environment.NewLine +
+				"		get {" + Environment.NewLine +
+				"			return field;" + Environment.NewLine +
+				"		}" + Environment.NewLine +
+				"	}" + Environment.NewLine +
+				"}"
+			);
+			
+			Assert.AreEqual (
+				"class TestClass" + Environment.NewLine +
+				"{" + Environment.NewLine +
+				"	readonly int field;" + Environment.NewLine +
+				"	public int Field {" + Environment.NewLine +
+				"		get {" + Environment.NewLine +
+				"			return field;" + Environment.NewLine +
+				"		}" + Environment.NewLine +
+				"		set {" + Environment.NewLine +
+				"			throw new System.NotImplementedException ();" + Environment.NewLine +
+				"		}" + Environment.NewLine +
+				"	}" + Environment.NewLine +
+				"}", result);
+		}
+		
 		[Test]
 		public void TestAddGet ()
 		{