Esempio n. 1
0
        /// <summary>
        /// Returns true if the node can have specified accessibility.
        /// </summary>
        /// <param name="node"></param>
        /// <param name="accessibility"></param>
        /// <param name="ignoreOverride">Ignore "override" modifier.</param>
        /// <returns></returns>
        public static bool IsValidAccessibility(SyntaxNode node, Accessibility accessibility, bool ignoreOverride = false)
        {
            if (node == null)
            {
                throw new ArgumentNullException(nameof(node));
            }

            switch (node.Parent?.Kind())
            {
            case SyntaxKind.NamespaceDeclaration:
            case SyntaxKind.CompilationUnit:
            {
                return(accessibility.Is(Accessibility.Public, Accessibility.Internal));
            }

            case SyntaxKind.StructDeclaration:
            {
                if (accessibility.ContainsProtected())
                {
                    return(false);
                }

                break;
            }
            }

            switch (node.Kind())
            {
            case SyntaxKind.ClassDeclaration:
            case SyntaxKind.InterfaceDeclaration:
            case SyntaxKind.StructDeclaration:
            case SyntaxKind.EnumDeclaration:
            {
                return(true);
            }

            case SyntaxKind.EventDeclaration:
            {
                var eventDeclaration = (EventDeclarationSyntax)node;

                ModifierKinds kinds = SyntaxInfo.ModifierListInfo(eventDeclaration).GetKinds();

                return((ignoreOverride || !kinds.Any(ModifierKinds.Override)) &&
                       (accessibility != Accessibility.Private || !kinds.Any(ModifierKinds.AbstractVirtualOverride)) &&
                       CheckProtectedInStaticOrSealedClass(node) &&
                       CheckAccessorAccessibility(eventDeclaration.AccessorList));
            }

            case SyntaxKind.IndexerDeclaration:
            {
                var indexerDeclaration = (IndexerDeclarationSyntax)node;

                ModifierKinds kinds = SyntaxInfo.ModifierListInfo(indexerDeclaration).GetKinds();

                return((ignoreOverride || !kinds.Any(ModifierKinds.Override)) &&
                       (accessibility != Accessibility.Private || !kinds.Any(ModifierKinds.AbstractVirtualOverride)) &&
                       CheckProtectedInStaticOrSealedClass(node) &&
                       CheckAccessorAccessibility(indexerDeclaration.AccessorList));
            }

            case SyntaxKind.PropertyDeclaration:
            {
                var propertyDeclaration = (PropertyDeclarationSyntax)node;

                ModifierKinds kinds = SyntaxInfo.ModifierListInfo(propertyDeclaration).GetKinds();

                return((ignoreOverride || !kinds.Any(ModifierKinds.Override)) &&
                       (accessibility != Accessibility.Private || !kinds.Any(ModifierKinds.AbstractVirtualOverride)) &&
                       CheckProtectedInStaticOrSealedClass(node) &&
                       CheckAccessorAccessibility(propertyDeclaration.AccessorList));
            }

            case SyntaxKind.MethodDeclaration:
            {
                var methodDeclaration = (MethodDeclarationSyntax)node;

                ModifierKinds kinds = SyntaxInfo.ModifierListInfo(methodDeclaration).GetKinds();

                return((ignoreOverride || !kinds.Any(ModifierKinds.Override)) &&
                       (accessibility != Accessibility.Private || !kinds.Any(ModifierKinds.AbstractVirtualOverride)) &&
                       CheckProtectedInStaticOrSealedClass(node));
            }

            case SyntaxKind.EventFieldDeclaration:
            {
                var eventFieldDeclaration = (EventFieldDeclarationSyntax)node;

                ModifierKinds kinds = SyntaxInfo.ModifierListInfo(eventFieldDeclaration).GetKinds();

                return((ignoreOverride || !kinds.Any(ModifierKinds.Override)) &&
                       (accessibility != Accessibility.Private || !kinds.Any(ModifierKinds.AbstractVirtualOverride)) &&
                       CheckProtectedInStaticOrSealedClass(node));
            }

            case SyntaxKind.ConstructorDeclaration:
            case SyntaxKind.DelegateDeclaration:
            case SyntaxKind.FieldDeclaration:
            case SyntaxKind.IncompleteMember:
            {
                return(CheckProtectedInStaticOrSealedClass(node));
            }

            case SyntaxKind.OperatorDeclaration:
            case SyntaxKind.ConversionOperatorDeclaration:
            {
                return(accessibility == Accessibility.Public);
            }

            case SyntaxKind.GetAccessorDeclaration:
            case SyntaxKind.SetAccessorDeclaration:
            case SyntaxKind.AddAccessorDeclaration:
            case SyntaxKind.RemoveAccessorDeclaration:
            case SyntaxKind.UnknownAccessorDeclaration:
            {
                var memberDeclaration = node.Parent?.Parent as MemberDeclarationSyntax;

                Debug.Assert(memberDeclaration != null, node.ToString());

                if (memberDeclaration != null)
                {
                    if (!CheckProtectedInStaticOrSealedClass(memberDeclaration))
                    {
                        return(false);
                    }

                    return(accessibility.IsMoreRestrictiveThan(GetAccessibility(memberDeclaration)));
                }

                return(false);
            }

            case SyntaxKind.LocalFunctionStatement:
            {
                return(false);
            }

            default:
            {
                Debug.Fail(node.Kind().ToString());
                return(false);
            }
            }

            bool CheckProtectedInStaticOrSealedClass(SyntaxNode declaration)
            {
                return(!accessibility.ContainsProtected() ||
                       (declaration.Parent as ClassDeclarationSyntax)?
                       .Modifiers
                       .ContainsAny(SyntaxKind.StaticKeyword, SyntaxKind.SealedKeyword) != true);
            }

            bool CheckAccessorAccessibility(AccessorListSyntax accessorList)
            {
                if (accessorList != null)
                {
                    foreach (AccessorDeclarationSyntax accessor in accessorList.Accessors)
                    {
                        Accessibility accessorAccessibility = GetExplicitAccessibility(accessor.Modifiers);

                        if (accessorAccessibility != Accessibility.NotApplicable)
                        {
                            return(accessorAccessibility.IsMoreRestrictiveThan(accessibility));
                        }
                    }
                }

                return(true);
            }
        }