@Test
public void getAromaticEdgeLabelTest() {

    IAtomContainer benzeneRing = builder.newInstance(IAtomContainer.class);
    for (int i = 0; i < 6; i++) {
        benzeneRing.addAtom(builder.newInstance(IAtom.class, "C"));
    }
    for (int i = 0; i < 6; i++) {
        IAtom a = benzeneRing.getAtom(i);
        IAtom b = benzeneRing.getAtom((i + 1) % 6);
        IBond bond = builder.newInstance(IBond.class, a, b);
        benzeneRing.addBond(bond);
        bond.setFlag(CDKConstants.ISAROMATIC, true);
    }
    AtomSignature signature = new AtomSignature(0, benzeneRing);
    for (int i = 0; i < 6; i++) {
        Assert.assertEquals("Failed for " + i, "p", signature.getEdgeLabel(i, (i + 1) % 6));
    }
}