public void Given_A_DeckThumbnail_Should_Invoke_SaveDeckThumbnail_Once()
{
// Arrange
const int expected = 1;
var deckThumbnailModel = new DeckThumbnail {
DeckId = 12312321
};
_deckFileSystem.SaveDeckThumbnail(Arg.Any <DeckThumbnail>()).Returns(23423);
// Act
_sut.SaveDeckThumbnail(deckThumbnailModel);
// Assert
_deckFileSystem.Received(expected).SaveDeckThumbnail(Arg.Any <DeckThumbnail>());
}
