def test_assert_evolution_should_fail_with_non_constant_expression_and_eq():
assert_invariant = assert_evolution(lambda: x, eq)
x = 1
assert_invariant()
assert_invariant()
x = 2
with raises(AssertionError):
assert_invariant()
def test_assert_evolution_should_work_with_increasing_expression_and_gt():
assert_increasing = assert_evolution(lambda: x, gt)
for x in range(20):
assert_increasing()
x -= 2
with raises(AssertionError):
assert_increasing()
def test_particleAcc_should_accelerate():
p = ParticleAcc(10, 200, 200, 100, 50)
def val():
return sqrt(p.vel.x ** 2 + p.vel.y ** 2)
print "vel = ", val()
p.move(1.0 / 60)
print "vel = ", val()
assert_invariant = assert_evolution(val, eq)
p.move(1.0 / 60)
assert_invariant()
p.move(1.0 / 60)
assert_invariant()
p.move(1.0 / 60)
assert_invariant()
print "ok!"
def test_assert_evolution_should_fail_with_constant_expression_and_gt():
assert_increasing = assert_evolution(lambda: x, gt)
x = 1
assert_increasing()
with raises(AssertionError):
assert_increasing()
def test_assert_evolution_should_work_with_constant_expression_and_eq():
assert_invariant = assert_evolution(lambda:x, eq)
for x in 'aaaaa':
assert_invariant()
