def test_dessin():
s = Systeme.exemple_bistable()
fig, ax = plt.subplots()
s.dessin(ax)
p, l1, l2, *_ = ax.get_children()
assert isinstance(l1, Line2D)
assert isinstance(l2, Line2D)
assert isinstance(p, PathCollection)
def test_exemple():
s1 = Systeme.exemple_simple()
assert not s1.verifications()
s2 = Systeme.exemple_bistable()
assert s2.verifications()