public void extend_date_extends_book_return_date()
{
//given
int randomBookId = rnd.Next(1, TestData.IssuedBooks.Count);
var issuedBook = TestData.IssuedBooks.Where(s => s.BookId == randomBookId);
moqBookService.Setup(m => m.GetIssuedBooks()).Returns(issuedBook);
moqBookAllocationService.Setup(m => m.ExtendReturndate(It.IsAny <IssuedBook>(), It.IsAny <int>())).Returns(true);
var sut = new BookStoreService(moqStudentService.Object, moqBookService.Object, moqBookAllocationService.Object);
//when
var result = sut.ExtendReturnDate(issuedBook.First().BookId, rnd.Next(1, 10));
//then
Assert.IsInstanceOfType(result, typeof(bool));
Assert.IsTrue(result);
moqBookService.Verify(v => v.GetIssuedBooks(), Times.Once);
moqBookAllocationService.Verify(v => v.ExtendReturndate(It.IsAny <IssuedBook>(), It.IsAny <int>()), Times.Once);
}