public void GetChaptersOfCourseAsyncShouldReturnEmptyListWhenNotCurrentPeriodIsFound()
{
//Arrange
var courseId = _random.NextPositive();
_periodRepositoryMock.Setup(repo => repo.GetCurrentPeriodAsync()).Throws <DataNotFoundException>();
//Act
var result = _service.GetChaptersOfCourseAsync(courseId).Result;
//Assert
_periodRepositoryMock.Verify(repo => repo.GetCurrentPeriodAsync(), Times.Once);
_chapterRepositoryMock.Verify(repo => repo.GetByCourseIdAsync(It.IsAny <int>(), It.IsAny <int>()), Times.Never);
Assert.That(result, Is.Empty);
}