def test_reflecting_a_vector_off_a_slanted_surface():
# Given
v = Vector(0, -1, 0)
n = Vector(sqrt(2) / 2, sqrt(2) / 2, 0)
# When
r = v.reflect(n)
# Then
assert r == Vector(1, 0, 0)
def test_reflecting_a_vector_approaching_at_45_degree():
# Given
v = Vector(1, -1, 0)
n = Vector(0, 1, 0)
# When
r = v.reflect(n)
# Then
assert r == Vector(1, 1, 0)
