public void Books_identity_is_its_ISBN() { var isbnForThisBook = "9781118714706"; var isbn = new ISBN(isbnForThisBook); var book = new Book(isbn); Assert.AreEqual(isbn, book.ISBN); Assert.AreEqual(isbnForThisBook, book.Id); }
public Book(ISBN isbn) { this.ISBN = isbn; this.Id = isbn.Number; }