old_contents: from tinyik import Actuator
  
  from .utils import x, y, z, theta, approx_eq
  
  
  def test_actuator_instantiation():
      two_joints_arm = Actuator(['z', 1., 'z', 1.])
      assert len(two_joints_arm.angles) == 2
      assert all(two_joints_arm.angles == 0.)
      assert all(two_joints_arm.ee == [2., 0., 0.])
  
      three_joints_arm = Actuator(['x', 1., 'y', 1., 'z', 1.])
      assert len(three_joints_arm.angles) == 3
      assert all(three_joints_arm.angles == 0.)
      assert all(three_joints_arm.ee == [3., 0., 0.])
  
      y_axis_dir_arm = Actuator(['z', [0., 1., 0.], 'z', [0., 1., 0.]])
      assert all(y_axis_dir_arm.ee == [0., 2., 0.])
  
  
  def test_actuator_angles():
      arm = Actuator(['z', 1., 'y', 1.])
      arm.angles = [theta, theta]
      assert approx_eq(arm.angles, [theta, theta])
      assert approx_eq(arm.ee, [x, y, -z])
  
  
  def test_actuator_ee():
      arm = Actuator(['z', 1., 'y', 1.])
      arm.ee = [x, -y, z]
      assert approx_eq(arm.ee, [x, -y, z])
      assert approx_eq(arm.angles, [-theta, -theta])
  
new_contents: from tinyik import Actuator
  
  from .utils import x, y, z, theta, approx_eq
  
  
  def test_actuator_instantiation():
      two_joints_arm = Actuator(['z', 1., 'z', 1.])
      assert len(two_joints_arm.angles) == 2
      assert all(two_joints_arm.angles == 0.)
      assert all(two_joints_arm.ee == [2., 0., 0.])
  
      three_joints_arm = Actuator(['x', 1., 'y', 1., 'z', 1.])
      assert len(three_joints_arm.angles) == 3
      assert all(three_joints_arm.angles == 0.)
      assert all(three_joints_arm.ee == [3., 0., 0.])
  
      y_axis_dir_arm = Actuator(['z', [0., 1., 0.], 'z', [0., 1., 0.]])
      assert all(y_axis_dir_arm.ee == [0., 2., 0.])
  
  
  def test_actuator_angles():
      arm = Actuator(['z', 1., 'y', 1.])
      arm.angles = [theta, theta]
      assert approx_eq(arm.angles, [theta, theta])
      assert approx_eq(arm.ee, [x, y, -z])
  
  
  def test_actuator_ee():
      arm = Actuator(['z', 1., 'y', 1.])
      arm.ee = [x, -y, z]
      assert approx_eq(arm.ee, [x, -y, z])
      assert approx_eq(arm.angles, [-theta, -theta])
  
  
  def test_multiple_actuator_ee():
      first_arm = Actuator(
          ['y', [0., 0., 0.01], 'x', [0., 0., 1.11], 'x', [0., 0., 1.225]])
      second_arm = Actuator(
          ['x', [0., 0., 1.175], 'x', [0., 0., 1.225], 'x', [0., 0., .1]])
      angles = [0, -1, 2.5]
      first_arm.angles = angles[:]
      first_arm.ee = first_arm.ee + [0., 0., 0.]
      assert approx_eq(first_arm.angles, angles)
      first_arm.ee = first_arm.ee + [0., 0., 0.]
      assert approx_eq(first_arm.angles, angles)
      assert approx_eq(second_arm.angles, [0., 0., 0.])
  
subject: Add test for #13