public void When_AddNewBook_Then_Data_Is_Added()
{
//arrange
var category = context.Categories.First();
var newBook = BookMock.GetValidBook(category);
var booksCountBeforeAdd = context.Books.Count();
//act
_bookRepository.Insert(newBook);
unitOfWork.SaveChanges();
//assert
var booksCountAfterAdd = context.Books.Count();
Assert.AreEqual(booksCountBeforeAdd + 1, booksCountAfterAdd);
}
