@Test
public void testCyclobutadiene() throws Exception {

    // anti-aromatic
    IAtomContainer molecule = TestMoleculeFactory.makeCyclobutadiene();
    addExplicitHydrogens(molecule);
    AtomContainerManipulator.percieveAtomTypesAndConfigureAtoms(molecule);
    lpcheck.saturate(molecule);
    StructureResonanceGenerator gRI = new StructureResonanceGenerator();
    IAtomContainerSet setOfMolecules = gRI.getStructures(molecule);
    Assert.assertEquals(2, setOfMolecules.getAtomContainerCount());
}