def test_pyrimidone_charge_recombination():
    """Recombine aromatic 1,3-separated charges to form pyrimidone."""
    eq_(standardize_smiles("[O-]c1[n+](C)cccc1"), "Cn1ccccc1=O")

def test_nitro_normalization():
    """Normalize nitro group."""
    eq_(standardize_smiles("C1(=CC=CC=C1)[N+](=O)[O-]"), "O=[N+]([O-])c1ccccc1")

def test_nitro_normalization5():
    """Normalize nitro group."""
    eq_(standardize_smiles("O[N+](=O)[O-]"), "O=[N+]([O-])O")

def test_disconnect_metal3():
    """Disconnect Pt in metal complex."""
    eq_(standardize_smiles("[Pt](Cl)(Cl)(O)(O)(NC(C)C)NC(C)C"), "[OH-].[OH-].[Cl-].[Cl-].[Pt+6].CC(C)[NH-].CC(C)[NH-]")

def test_disconnect_metal5():
    """Silver carbonate. Unsure about this one."""
    eq_(standardize_smiles("[Ag]OC(=O)O[Ag]"), "[Ag+].[Ag+].O=C([O-])[O-]")

def test_disconnect_metal6():
    """"""
    eq_(standardize_smiles("C1(CCCCC1)[Zn]Br"), "[Zn+2].[Br-].[CH-]1CCCCC1")

def test_disconnect_metal():
    """Break metal-organic covalent bonds."""
    eq_(standardize_smiles("[Na]OC(=O)c1ccccc1"), "[Na+].O=C([O-])c1ccccc1")

def test_charge_to_protonated_atom6():
    """Shift positive charge from nonprotonated to protonated atom."""
    eq_(standardize_smiles("[nH]1ccc(=[N+](C)C)cc1"), "CN(C)c1cc[nH+]cc1")

def test_charge_to_protonated_atom7():
    """Shift positive charge from nonprotonated to protonated atom."""
    eq_(standardize_smiles("CNc1cc[n+](C)cc1"), "C[NH+]=c1ccn(C)cc1")

def test_1_5_aromatic_charge_recombination2():
    """Recombine aromatic 1,5-separated charges."""
    eq_(standardize_smiles("C[n+]1ccc([N-]C)cc1"), "CN=c1ccn(C)cc1")

def test_aromaticity2():
    """Both rings should be aromatic."""
    eq_(standardize_smiles("C[N]1C=NC2=C1C(=O)N(C)C(=O)N2C"), "Cn1cnc2c1c(=O)n(C)c(=O)n2C")
    eq_(standardize_smiles("Cn1cnc2c1c(=O)n(C)c(=O)n2C"), "Cn1cnc2c1c(=O)n(C)c(=O)n2C")

def test_1_5_aromatic_charge_recombination():
    """Recombine aromatic 1,5-separated charges."""
    eq_(standardize_smiles("[n-]1ccc(=[N+](C)C)cc1"), "CN(C)c1ccncc1")

def test_1_5_nonaromatic_charge_recombination():
    """Recombine non-aromatic 1,5-separated charges."""
    eq_(standardize_smiles("C[N-]C=CC=[N+](C)C"), "CN=CC=CN(C)C")

def test_pyrimidone_charge_recombination2():
    """Recombine aromatic 1,3-separated charges to form pyrimidone."""
    eq_(
        standardize_smiles("COc1cc2ccc3c4c(OC)cc(OC)c(OC)c4c([O-])[n+](C)c3c2cc1OC"),
        "COc1cc2ccc3c4c(OC)cc(OC)c(OC)c4c(=O)n(C)c3c2cc1OC",
    )

def test_charge_preservation2():
    """"""
    eq_(standardize_smiles("[Cl-].C[NH+](C)C"), "[Cl-].C[NH+](C)C")

def test_charge_to_protonated_atom8():
    """Shift positive charge from nonprotonated to protonated atom."""
    eq_(standardize_smiles("C[n+]1ccc2[nH]ccc2c1"), "Cn1ccc2[nH+]ccc-2c1")

def test_aromaticity3():
    """Redo incorrect aromatization."""
    eq_(standardize_smiles("C=Cc1ccc2c(c1)NC(=O)/C/2=C\\c1ccc[nH]1"), "C=Cc1ccc2c(c1)NC(=O)/C2=C\\c1ccc[nH]1")
    eq_(standardize_smiles("C=Cc1ccc2c(c1)[nH]c(=O)/c/2=C\\c1ccc[nH]1"), "C=Cc1ccc2c(c1)NC(=O)/C2=C\\c1ccc[nH]1")

def test_charge_to_protonated_atom9():
    """Shift positive charge from nonprotonated to protonated atom."""
    eq_(standardize_smiles("CNC=CC=[N+](C)C"), "C[NH+]=CC=CN(C)C")

def test_stereochemistry():
    """Check stereochemistry is correctly perceived."""
    eq_(standardize_smiles("Cl\\C=C/Cl"), "Cl/C=C\\Cl")

def test_transform_maintains_ring():
    """Ensure no transforms inadvertently breaks open rings."""
    eq_(standardize_smiles("[nH]1ccc2cccc[n+]12"), "c1cc2ccccn2[nH+]1")