protected override bool TryInitializeState(
			Document document, SemanticModel model, SyntaxNode node, CancellationToken cancellationToken,
			out INamedTypeSymbol classType, out INamedTypeSymbol abstractClassType)
		{
			var baseClassNode = node as TypeSyntax;
			if (baseClassNode != null && baseClassNode.Parent is BaseTypeSyntax &&
				baseClassNode.Parent.IsParentKind(SyntaxKind.BaseList) &&
				((BaseTypeSyntax)baseClassNode.Parent).Type == baseClassNode)
			{
				if (baseClassNode.Parent.Parent.IsParentKind(SyntaxKind.ClassDeclaration))
				{
					abstractClassType = model.GetTypeInfo(baseClassNode, cancellationToken).Type as INamedTypeSymbol;
					cancellationToken.ThrowIfCancellationRequested();

					if (abstractClassType.IsAbstractClass())
					{
						var classDecl = baseClassNode.Parent.Parent.Parent as ClassDeclarationSyntax;
						classType = model.GetDeclaredSymbol(classDecl, cancellationToken) as INamedTypeSymbol;

						return classType != null && abstractClassType != null;
					}
				}
			}

			classType = null;
			abstractClassType = null;
			return false;
		}

        private static async Task<Document> MakeMock(Document document, SyntaxNode invokationSyntax,
            CancellationToken cancellationToken)
        {
            var testSemanticModel = await document.GetSemanticModelAsync(cancellationToken).ConfigureAwait(false);

            var testInitMethodDecl = TestSemanticHelper.GetTestInitializeMethod(testSemanticModel);

            var declaredFields = testInitMethodDecl.Parent.ChildNodes().OfType<FieldDeclarationSyntax>().ToArray();

            var suts = testInitMethodDecl.GetSuts(testSemanticModel, declaredFields);

            var memberAccessExpressions = invokationSyntax.DescendantNodes()
                .OfType<ExpressionSyntax>()
                .Where(x => x is InvocationExpressionSyntax || x is MemberAccessExpressionSyntax)
                .Select(expr =>
                {
                    var memberAccess = expr as MemberAccessExpressionSyntax;
                    var invokationExpression = expr as InvocationExpressionSyntax;
                    var expression = invokationExpression == null ? memberAccess : invokationExpression.Expression;
                    return expression;
                });

            var invokedMethodsOfMocks = memberAccessExpressions.SelectMany(expressionSyntax => MocksAnalyzingEngine.GetInvokedMethodsOfMock(expressionSyntax, testSemanticModel, suts))
                                                               .DistinctBy(x => string.Join(",", x.FieldsToSetup.SelectMany(y => y.Field.Select(z => z))) + "," + x.MethodOrPropertySymbol)
                                                               .ToArray();

            if (invokedMethodsOfMocks.Length == 0)
                return document;

            var editor = await DocumentEditor.CreateAsync(document, cancellationToken).ConfigureAwait(false);

            ChangesMaker.ApplyChanges(invokationSyntax, editor, invokedMethodsOfMocks);

            return editor.GetChangedDocument();
        }

 private static Solution UpdateMainDocument(Document document, SyntaxNode root, MethodDeclarationSyntax method, IEnumerable<IGrouping<Document, ReferenceLocation>> documentGroups)
 {
     var mainDocGroup = documentGroups.FirstOrDefault(dg => dg.Key.Equals(document));
     SyntaxNode newRoot;
     if (mainDocGroup == null)
     {
         newRoot = root.ReplaceNode(method, method.AddModifiers(staticToken));
     }
     else
     {
         var diagnosticNodes = mainDocGroup.Select(referenceLocation => root.FindNode(referenceLocation.Location.SourceSpan)).ToList();
         newRoot = root.TrackNodes(diagnosticNodes.Union(new[] { method }));
         newRoot = newRoot.ReplaceNode(newRoot.GetCurrentNode(method), method.AddModifiers(staticToken));
         foreach (var diagnosticNode in diagnosticNodes)
         {
             var token = newRoot.FindToken(diagnosticNode.GetLocation().SourceSpan.Start);
             var tokenParent = token.Parent;
             if (token.Parent.IsKind(SyntaxKind.IdentifierName)) continue;
             var invocationExpression = newRoot.GetCurrentNode(diagnosticNode).FirstAncestorOrSelfOfType<InvocationExpressionSyntax>()?.Expression;
             if (invocationExpression == null || invocationExpression.IsKind(SyntaxKind.IdentifierName)) continue;
             var memberAccess = invocationExpression as MemberAccessExpressionSyntax;
             if (memberAccess == null) continue;
             var newMemberAccessParent = memberAccess.Parent.ReplaceNode(memberAccess, memberAccess.Name)
                 .WithAdditionalAnnotations(Formatter.Annotation);
             newRoot = newRoot.ReplaceNode(memberAccess.Parent, newMemberAccessParent);
         }
     }
     var newSolution = document.Project.Solution.WithDocumentSyntaxRoot(document.Id, newRoot);
     return newSolution;
 }

        internal static bool HasFlagsAttribute(SyntaxNode node, SemanticModel semanticModel)
        {
            var symbol = semanticModel.GetDeclaredSymbol(node);

            return symbol != null && 
                symbol.GetAttributes().Any(attribute => attribute.AttributeClass.Is(KnownType.System_FlagsAttribute));
        }

        private Task<Solution> UseExpressionBodiedMemberAsync(Document document, SyntaxNode root, SyntaxNode statement)
        {
            var returnStatement = (ReturnStatementSyntax) statement;
            var expression = returnStatement.Expression;
            var arrowClause = SyntaxFactory.ArrowExpressionClause(expression);

            var property = statement.AncestorsAndSelf().OfType<PropertyDeclarationSyntax>().FirstOrDefault();
            if (property != null)
            {
                var newProperty = property.RemoveNode(property.AccessorList, SyntaxRemoveOptions.KeepNoTrivia)
                                          .WithExpressionBody(arrowClause)
                                          .WithSemicolonToken(SyntaxFactory.Token(SyntaxKind.SemicolonToken));


                root = root.ReplaceNode(property, newProperty);
            }

            var method = statement.AncestorsAndSelf().OfType<MethodDeclarationSyntax>().FirstOrDefault();
            if (method != null)
            {
                root = root.ReplaceNode(method, method.RemoveNode(method.Body, SyntaxRemoveOptions.KeepNoTrivia)
                                                      .WithExpressionBody(arrowClause)
                                                      .WithSemicolonToken(SyntaxFactory.Token(SyntaxKind.SemicolonToken)));
            }

            return Task.FromResult(document.WithSyntaxRoot(root).Project.Solution);
        }

        private static bool IsNameableNode(SyntaxNode node)
        {
            switch (node.Kind())
            {
                case SyntaxKind.ClassDeclaration:
                case SyntaxKind.ConstructorDeclaration:
                case SyntaxKind.ConversionOperatorDeclaration:
                case SyntaxKind.DelegateDeclaration:
                case SyntaxKind.DestructorDeclaration:
                case SyntaxKind.EnumDeclaration:
                case SyntaxKind.EnumMemberDeclaration:
                case SyntaxKind.EventDeclaration:
                case SyntaxKind.IndexerDeclaration:
                case SyntaxKind.InterfaceDeclaration:
                case SyntaxKind.MethodDeclaration:
                case SyntaxKind.NamespaceDeclaration:
                case SyntaxKind.OperatorDeclaration:
                case SyntaxKind.PropertyDeclaration:
                case SyntaxKind.StructDeclaration:
                    return true;

                case SyntaxKind.VariableDeclarator:
                    // Could be a regular field or an event field.
                    return node.FirstAncestorOrSelf<BaseFieldDeclarationSyntax>() != null;

                default:
                    return false;
            }
        }

 private IReadOnlyList<MemberDeclarationSyntax> GetValidMembers(SyntaxNode node)
 {
     return CSharpCodeModelService
         .GetChildMemberNodes(node)
         .Where(n => !n.IsKind(SyntaxKind.IncompleteMember))
         .ToArray();
 }

        private static ISymbol GetDeclaredSymbol(SemanticModel model, SyntaxNode node, bool getSymbol, CancellationToken cancellationToken)
        {
            if (!getSymbol)
            {
                return null;
            }

            var declaredSymbol = model.GetDeclaredSymbol(node, cancellationToken);

            // For namespace declarations, GetDeclaredSymbol returns a compilation scoped namespace symbol,
            // which includes declarations across the compilation, including those in referenced assemblies.
            // However, we are only interested in the namespace symbol scoped to the compilation's source assembly.
            var namespaceSymbol = declaredSymbol as INamespaceSymbol;
            if (namespaceSymbol != null && namespaceSymbol.ConstituentNamespaces.Length > 1)
            {
                var assemblyToScope = model.Compilation.Assembly;
                var assemblyScopedNamespaceSymbol = namespaceSymbol.ConstituentNamespaces.FirstOrDefault(ns => ns.ContainingAssembly == assemblyToScope);
                if (assemblyScopedNamespaceSymbol != null)
                {
                    Debug.Assert(assemblyScopedNamespaceSymbol.ConstituentNamespaces.Length == 1);
                    declaredSymbol = assemblyScopedNamespaceSymbol;
                }
            }

            return declaredSymbol;
        }

    private static void AddCodeFixWithNewPublicConstructor(CodeFixContext context, SyntaxNode root,
      Diagnostic diagnostic, ClassDeclarationSyntax classNode)
    {
      // Generated from http://roslynquoter.azurewebsites.net/
      var constructor = SyntaxFactory.ConstructorDeclaration(classNode.Identifier)
        .WithModifiers(
          SyntaxFactory.TokenList(
            SyntaxFactory.Token(SyntaxKind.PublicKeyword)))
        .WithParameterList(SyntaxFactory.ParameterList()
          .WithOpenParenToken(
            SyntaxFactory.Token(SyntaxKind.OpenParenToken))
          .WithCloseParenToken(
            SyntaxFactory.Token(
              SyntaxKind.CloseParenToken)))
        .WithBody(SyntaxFactory.Block()
          .WithOpenBraceToken(
            SyntaxFactory.Token(
              SyntaxKind.OpenBraceToken))
          .WithCloseBraceToken(
            SyntaxFactory.Token(
              SyntaxKind.CloseBraceToken))).NormalizeWhitespace().WithAdditionalAnnotations(Formatter.Annotation);
      var newClassNode = classNode.AddMembers(constructor);
      var newRoot = root.ReplaceNode(classNode, newClassNode);

      context.RegisterCodeFix(
        CodeAction.Create(
          CheckConstructorsAnalyzerPublicConstructorCodeFixConstants.AddPublicConstructorDescription,
          _ => Task.FromResult(context.Document.WithSyntaxRoot(newRoot)),
          CheckConstructorsAnalyzerPublicConstructorCodeFixConstants.AddPublicConstructorDescription), diagnostic);
    }

 public static SyntaxNode AddWarningCommentIf(this SyntaxGenerator g, bool condition, SyntaxNode node)
 {
    if (condition)
       return g.AddWarningComment(node);
    else
       return node;
 }

		public IEnumerable<IHalsteadMetrics> Calculate(SyntaxNode root)
		{
			var analyzer = new HalsteadAnalyzer();
			var childNodes = root.ChildNodes().AsArray();

			var types = childNodes.Where(n => n.IsKind(SyntaxKind.ClassDeclaration) || n.IsKind(SyntaxKind.StructDeclaration))
				.AsArray();
			var methods = types.SelectMany(n => n.ChildNodes().Where(_isMethod));
			var getProperties = types.SelectMany(n => n.ChildNodes().Where(IsGetProperty));
			var setProperties = types.SelectMany(n => n.ChildNodes().Where(IsSetProperty));
			var looseMethods = childNodes.Where(_isMethod);
			var looseGetProperties = childNodes.Where(IsGetProperty);
			var looseSetProperties = childNodes.Where(IsSetProperty);
			var members = methods.Concat(getProperties)
								 .Concat(setProperties)
								 .Concat(looseMethods)
								 .Concat(looseGetProperties)
								 .Concat(looseSetProperties)
								 .AsArray();
			if (members.Any())
			{
				return members.Select(analyzer.Calculate);
			}

			var statements = childNodes.Length == 0
				? root.DescendantNodesAndTokens().Select(x => SyntaxFactory.ParseStatement(x.ToFullString(), 0, new CSharpParseOptions(kind: SourceCodeKind.Script, preprocessorSymbols: new string[0])))
				: childNodes.Select(x => SyntaxFactory.ParseStatement(x.ToFullString(), 0, new CSharpParseOptions(kind: SourceCodeKind.Script, preprocessorSymbols: new string[0])));

			var fakeMethod = SyntaxFactory.MethodDeclaration(SyntaxFactory.PredefinedType(SyntaxFactory.Token(SyntaxKind.VoidKeyword)), "fake")
				.WithBody(SyntaxFactory.Block(statements));
			return new[]
				   {
					   analyzer.Calculate(fakeMethod)
				   };
		}

    private static void AddCodeFix(CodeFixContext context, SyntaxNode root,
      Diagnostic diagnostic, ClassDeclarationSyntax classNode)
    {
      var newRoot = IsBusinessObjectSerializableMakeSerializableCodeFix.AddAttribute(
        root, classNode, IsBusinessObjectSerializableMakeSerializableCodeFixConstants.SerializableName);

      if (!root.HasUsing(IsBusinessObjectSerializableMakeSerializableCodeFixConstants.SystemNamespace))
      {
        newRoot = (newRoot as CompilationUnitSyntax).AddUsings(
          SyntaxFactory.UsingDirective(SyntaxFactory.ParseName(
            IsBusinessObjectSerializableMakeSerializableCodeFixConstants.SystemNamespace)));
      }

      if (!root.HasUsing(IsBusinessObjectSerializableMakeSerializableCodeFixConstants.CslaSerializationNamespace))
      {
        newRoot = (newRoot as CompilationUnitSyntax).AddUsings(
          SyntaxFactory.UsingDirective(SyntaxFactory.ParseName(
            IsBusinessObjectSerializableMakeSerializableCodeFixConstants.CslaSerializationNamespace)));
      }

      context.RegisterCodeFix(
        CodeAction.Create(
          IsBusinessObjectSerializableMakeSerializableCodeFixConstants.AddSerializableAndUsingDescription,
          _ => Task.FromResult<Document>(context.Document.WithSyntaxRoot(newRoot))), diagnostic);
    }

 private ITriviaSavedResult CreateResult(
     SyntaxNode root,
     Dictionary<TriviaLocation, SyntaxAnnotation> annotations,
     Dictionary<TriviaLocation, IEnumerable<SyntaxTrivia>> triviaList)
 {
     return new Result(root, _endOfLineKind, annotations, triviaList);
 }

 private SyntaxNode ReplaceTokens(
     SyntaxNode root,
     IEnumerable<SyntaxToken> oldTokens,
     Func<SyntaxToken, SyntaxToken, SyntaxToken> computeReplacementToken)
 {
     return root.ReplaceTokens(oldTokens, (o, n) => computeReplacementToken(o, n));
 }

        private Document CreateCodeFix(Document document, Diagnostic diagnostic, SyntaxNode syntaxRoot)
        {
            SyntaxNode newSyntaxRoot = syntaxRoot;
            var node = syntaxRoot.FindNode(diagnostic.Location.SourceSpan);
            var indentationOptions = IndentationOptions.FromDocument(document);

            switch (node.Kind())
            {
            case SyntaxKind.ClassDeclaration:
            case SyntaxKind.InterfaceDeclaration:
            case SyntaxKind.StructDeclaration:
            case SyntaxKind.EnumDeclaration:
                newSyntaxRoot = this.RegisterBaseTypeDeclarationCodeFix(syntaxRoot, (BaseTypeDeclarationSyntax)node, indentationOptions);
                break;

            case SyntaxKind.AccessorList:
                newSyntaxRoot = this.RegisterPropertyLikeDeclarationCodeFix(syntaxRoot, (BasePropertyDeclarationSyntax)node.Parent, indentationOptions);
                break;

            case SyntaxKind.Block:
                newSyntaxRoot = this.RegisterMethodLikeDeclarationCodeFix(syntaxRoot, (BaseMethodDeclarationSyntax)node.Parent, indentationOptions);
                break;

            case SyntaxKind.NamespaceDeclaration:
                newSyntaxRoot = this.RegisterNamespaceDeclarationCodeFix(syntaxRoot, (NamespaceDeclarationSyntax)node, indentationOptions);
                break;
            }

            return document.WithSyntaxRoot(newSyntaxRoot);
        }

 SyntaxNode AddNewModifier(SyntaxNode node)
 {
     SyntaxToken newToken = SyntaxFactory.Token(SyntaxKind.NewKeyword);
     switch (node.Kind())
     {
         //couldn't find a common base
         case SyntaxKind.IndexerDeclaration:
             var indexer = (IndexerDeclarationSyntax)node;
             return indexer.AddModifiers(newToken);
         case SyntaxKind.ClassDeclaration:
             var classDecl = (ClassDeclarationSyntax)node;
             return classDecl.AddModifiers(newToken);
         case SyntaxKind.PropertyDeclaration:
             var propDecl = (PropertyDeclarationSyntax)node;
             return propDecl.AddModifiers(newToken);
         case SyntaxKind.MethodDeclaration:
             var methDecl = (MethodDeclarationSyntax)node;
             return methDecl.AddModifiers(newToken);
         case SyntaxKind.StructDeclaration:
             var structDecl = (StructDeclarationSyntax)node;
             return structDecl.AddModifiers(newToken);
         case SyntaxKind.EnumDeclaration:
             var enumDecl = (EnumDeclarationSyntax)node;
             return enumDecl.AddModifiers(newToken);
         case SyntaxKind.InterfaceDeclaration:
             var intDecl = (InterfaceDeclarationSyntax)node;
             return intDecl.AddModifiers(newToken);
         case SyntaxKind.DelegateDeclaration:
             var deleDecl = (DelegateDeclarationSyntax)node;
             return deleDecl.AddModifiers(newToken);
         default:
             return node;
     }
 }

 private static bool IsInitializer(SyntaxNode node)
 {
     return node.IsKind(SyntaxKind.ArrayInitializerExpression) ||
         node.IsKind(SyntaxKind.CollectionInitializerExpression) ||
         node.IsKind(SyntaxKind.AnonymousObjectCreationExpression) ||
         node.IsKind(SyntaxKind.ObjectInitializerExpression);
 }

 private static IEnumerable<SyntaxToken> GetAsyncOrAwaitTokens(SyntaxNode node)
 {
     return from token in node.DescendantTokens()
            where token.IsKind(SyntaxKind.IdentifierToken) &&
            AsyncOrAwait.Contains(token.ToString())
            select token;
 }

 private async Task<Document> AddNonSerializedAttribute(Document document, SyntaxNode fieldNode, CancellationToken cancellationToken)
 {
     var editor = await DocumentEditor.CreateAsync(document, cancellationToken).ConfigureAwait(false);
     var attr = editor.Generator.Attribute(editor.Generator.TypeExpression(WellKnownTypes.NonSerializedAttribute(editor.SemanticModel.Compilation)));
     editor.AddAttribute(fieldNode, attr);
     return editor.GetChangedDocument();
 }

            private bool CompareAttributes(
                AttributeSyntax oldAttribute,
                AttributeSyntax newAttribute,
                SyntaxNode newNodeParent,
                CodeModelEventQueue eventQueue)
            {
                Debug.Assert(oldAttribute != null && newAttribute != null);

                bool same = true;

                if (!CompareNames(oldAttribute.Name, newAttribute.Name))
                {
                    EnqueueChangeEvent(newAttribute, newNodeParent, CodeModelEventType.Rename, eventQueue);
                    same = false;
                }

                // If arguments have changed enqueue a element changed (arguments changed) node
                if (!CompareAttributeArguments(oldAttribute.ArgumentList, newAttribute.ArgumentList))
                {
                    EnqueueChangeEvent(newAttribute, newNodeParent, CodeModelEventType.ArgChange, eventQueue);
                    same = false;
                }

                return same;
            }