* If the mutation doesn't happen, the candidates should be returned unaltered.
*/
@Test
public void testSomeMutations()
{
TreeFactory treeFactory = new TreeFactory(1, 4, new Probability(0.6d), new Probability(0.2d));
EvolutionaryOperator<Node> mutation = new TreeMutation(treeFactory,
Probability.ONE); // Probability of 1 means guaranteed mutations.
List<Node> candidates = treeFactory.generateInitialPopulation(20, ExamplesTestUtils.getRNG());
Map<Node, Node> distinctTrees = new IdentityHashMap<Node, Node>();