public void GIVEN_unchanged_aggregate_root_WHEN_attempting_to_save_THEN_does_not_throw_any_exception()
{
// Arrange
var repository = new TestRepository(_mockFactory.Object, _mockEventStore.Object);
var aggregateRoot = new TestAggregateRoot();
aggregateRoot.LoadFromStream(_events.ToList());
// Act
Func <Task> act = async() => await repository.SaveAsync(aggregateRoot);
// Assert
act.Should()
.NotThrow <Exception>();
_mockEventStore.Verify(m => m.SaveAsync(It.IsAny <IReadOnlyCollection <Event> >(), It.IsAny <string>(), It.IsAny <CancellationToken>()), Times.Never());
}