EDIT

import eu.etaxonomy.cdm.model.name.NomenclaturalStatus;

import eu.etaxonomy.cdm.model.name.NomenclaturalStatusType;

        //even with nom. illeg. the name with date should come first

        NomenclaturalStatus illegStatus = NomenclaturalStatus.NewInstance(NomenclaturalStatusType.ILLEGITIMATE());

        botName5.addStatus(illegStatus);

        Assert.assertEquals("basionym with date should comes first", botName5, list.get(0).getName());

        Assert.assertEquals(botName3, list.get(1).getName());

        Assert.assertEquals(botName4, list.get(2).getName());

        Assert.assertEquals(botName2, list.get(3).getName());

    @Test

    public void testCompare_BasionymGroupsWithNomIlleg() {

        NomenclaturalStatus illegStatus = NomenclaturalStatus.NewInstance(NomenclaturalStatusType.ILLEGITIMATE());

        botName4.addStatus(illegStatus);

        //2 basionym groups

        HomotypicalGroup homotypicalGroup = botName2.getHomotypicalGroup();

        taxon1.addHeterotypicSynonymName(botName3);

        taxon1.addHeterotypicSynonymName(botName5, homotypicalGroup, null, null);

        botName3.addBasionym(botName5);

        synonym2 = taxon1.addHeterotypicSynonymName(botName2).getSynonym();

        taxon1.addHeterotypicSynonymName(botName4, homotypicalGroup, null, null);

//        botName2.addBasionym(botName4);

        list.addAll(taxon1.getSynonyms());

        Collections.sort(list, new HomotypicGroupTaxonComparator(null));

        Assert.assertEquals("basionym for non nom. illeg. group should come first", botName2, list.get(0).getName());

        Assert.assertEquals(botName5, list.get(1).getName());

        Assert.assertEquals(botName3, list.get(2).getName());

        Assert.assertEquals("Nom illeg should come last", botName4, list.get(3).getName());

        //name having a nom. illeg. as basionym should stay in its basionym group

        //NOTE: this is dirty data as nom. illeg. is not allowed as basionym by the code

        botName2.addBasionym(botName4);

        Collections.sort(list, new HomotypicGroupTaxonComparator(null));

        Assert.assertEquals("basionym for non nom. illeg. group should come first", botName5, list.get(0).getName());

        Assert.assertEquals(botName3, list.get(1).getName());

        Assert.assertEquals("Nom illeg basionym group should come last", botName4, list.get(2).getName());

        Assert.assertEquals("Names with nom. illeg. as basionym should stay in basionym group", botName2, list.get(3).getName());

        //non basionym nom. illeg. should not change the order

        botName4.removeStatus(illegStatus);

        botName2.addStatus(illegStatus);

        Collections.sort(list, new HomotypicGroupTaxonComparator(null));

        Assert.assertEquals("basionym for non nom. illeg. group should come first", botName4, list.get(0).getName());

        Assert.assertEquals(botName2, list.get(1).getName());

        Assert.assertEquals("Nom illeg basionym group should come last", botName5, list.get(2).getName());

        Assert.assertEquals("Names with nom. illeg. as basionym should stay in basionym group", botName3, list.get(3).getName());

    }