def test_multiple_amounts():
substance = Substance()
sodium = Component("[Na+]")
chloride = Component("[Cl-]")
substance.add_component(sodium, MoleFraction(0.75))
substance.add_component(sodium, ExactAmount(1))
substance.add_component(chloride, MoleFraction(0.25))
substance.add_component(chloride, ExactAmount(1))
assert substance.number_of_components == 2
sodium_amounts = substance.get_amounts(sodium)
chlorine_amounts = substance.get_amounts(chloride)
assert len(sodium_amounts) == 2
assert len(chlorine_amounts) == 2
molecule_counts = substance.get_molecules_per_component(6)
assert len(molecule_counts) == 2
assert molecule_counts[sodium.identifier] == 4
assert molecule_counts[chloride.identifier] == 2
def test_add_mole_fractions():
substance = Substance()
substance.add_component(Component("C"), MoleFraction(0.5))
substance.add_component(Component("C"), MoleFraction(0.5))
assert substance.number_of_components == 1
amounts = substance.get_amounts(substance.components[0])
assert len(amounts) == 1
amount = next(iter(amounts))
assert isinstance(amount, MoleFraction)
assert np.isclose(amount.value, 1.0)
