private AttributeListSyntax CreateInternalVisibleToAttributeList(Project project, Project[] allProjects)
        {
            var testProjects = allProjects.Where(x => x.ProjectReferences.Any(y => y.ProjectId == project.Id)).ToArray();
            if (testProjects.Length == 0)
                return null;

            List<AttributeSyntax> attrs = testProjects.Select(CreateInternalVisibleToAttribute).ToList();

            var attributeList = new SeparatedSyntaxList<AttributeSyntax>();
            attributeList = attributeList.AddRange(attrs);

            var assemblyLevelSpecifier =
                SyntaxFactory.AttributeTargetSpecifier(SyntaxFactory.Token(SyntaxKind.AssemblyKeyword));

            return SyntaxFactory.AttributeList(assemblyLevelSpecifier, attributeList);
        }