@Test
public void iminesDetectionDoesntCauseNPE() throws Exception {

    IAtomContainer pyrazole = new AtomContainer(6, 6, 0, 0);
    pyrazole.addAtom(atom("H", 0, 0));
    pyrazole.addAtom(atom("N", 0, 0));
    pyrazole.addAtom(atom("C", 0, 1));
    pyrazole.addAtom(atom("C", 0, 1));
    pyrazole.addAtom(atom("C", 0, 1));
    pyrazole.addAtom(atom("N", 0, 0));
    pyrazole.addBond(0, 1, IBond.Order.SINGLE);
    pyrazole.addBond(1, 2, IBond.Order.SINGLE);
    pyrazole.addBond(2, 3, IBond.Order.DOUBLE);
    pyrazole.addBond(3, 4, IBond.Order.SINGLE);
    pyrazole.addBond(4, 5, IBond.Order.DOUBLE);
    pyrazole.addBond(1, 5, IBond.Order.SINGLE);
    CircularFingerprinter circ = new CircularFingerprinter(CircularFingerprinter.CLASS_FCFP2);
    assertNotNull(circ.getBitFingerprint(pyrazole));
}