public void SelectionStrategyReturnsNull_ThrowsException() { Assertions.AssertThrowAggretateExceptionOfType(() => { var selectionStrategy = A.Fake <ISelectionStrategy>(); A.CallTo(() => selectionStrategy.SelectChromosome()).Returns(null); var childrenGenerator = new ChildrenGenerator(A.Fake <ICrossoverManager>(), new BasicMutationProbabilityManager(0), selectionStrategy); childrenGenerator.GenerateChildren(GetPopulation(1), 1, 0, null); }, typeof(GeneticAlgorithmException)); }