public async Task ProcessModifiedFiles_OnEmptyModifiedFiles_ReturnEmptyEnumerable() { var logger = Substitute.For <ILogger>(); var emptyList = new List <CodeFragment>(); var( addedFragments, modifiedFragments, deletedFragments ) = await _fileProcessor.ProcessModifiedFiles(new Collection <string>(), logger); CollectionAssert.AreEquivalent(emptyList, addedFragments); CollectionAssert.AreEquivalent(emptyList, modifiedFragments); CollectionAssert.AreEquivalent(emptyList, deletedFragments); }