public void BookIdIsNull()
{
// Arrange
var mock = new Mock <IUnitOfWork>();
LibService service = new LibService(mock.Object);
// Act and assert
Assert.ThrowsException <System.ArgumentNullException>(() => service.ReturnBook(5, null));
}
public void BookIsNotFound()
{
// Arrange
var mock = new Mock <IUnitOfWork>();
mock.Setup(a => a.Books.Get(1)).Returns((Book)null);
mock.Setup(a => a.Readers.Get(1)).Returns(new Reader());
LibService service = new LibService(mock.Object);
// Act and assert
Assert.ThrowsException <System.InvalidOperationException>(() => service.ReturnBook(1, 1));
}