public async Task TestIfGetAllPageCategoryNamesThrowsError()
        {
            var context = PCHUBDbContextInMemoryInitializer.InitializeContext();

            var adminPageService = new Areas.Administration.Services.AdminIndexPageServices(context);

            await Assert.ThrowsAsync <NullReferenceException>(async() =>
            {
                await adminPageService.GetAllPageCategoryNamesAsync();
            });
        }
        public async Task TestIfGetAllPageCategoryNamesWorksAccordingly(string pagename, string categoryName)
        {
            var context = PCHUBDbContextInMemoryInitializer.InitializeContext();

            var adminPageService = new Areas.Administration.Services.AdminIndexPageServices(context);


            await adminPageService.CreateIndexPageAsync(pagename);


            var form = new CreatePageCategoryViewModel();

            form.AllHref      = "AllHref";
            form.AllName      = "AllLaptops";
            form.CategoryName = categoryName;

            await adminPageService.AddIndexPageCategoryAsync(form, "pictureUrl", "PictureName");

            var result = await adminPageService.GetAllPageCategoryNamesAsync();

            Assert.Contains(result, (str) => str == categoryName);
        }