def test_add_bond():
m = mx.Molecule()
v = mx.Atom()
w = mx.Atom()
m.add_atom(v)
m.add_atom(w)
m.add_bond(v, w)
assert len(m.bonds()) == 1
assert len(m.atoms()) == 2
def test_atom():
v = mx.Atom(symbol='H')
assert v.element.number == 1
assert v.element.symbol == 'H'
assert v.element.mass == 1.00800
v = mx.Atom(number=1)
assert v.element.number == 1
assert v.element.symbol == 'H'
assert v.element.mass == 1.00800
def test_atom_unknown_atom():
with pytest.raises(KeyError):
v = mx.Atom(symbol='X')
def test_atom_element_number_mismatch():
with pytest.raises(AssertionError):
v = mx.Atom(number=1, symbol='C')
def test_add_atom():
m = mx.Molecule()
v = mx.Atom()
m.add_atom(v)
assert len(m.atoms()) == 1