old_contents: import unittest
  import numpy as np
  from numpy import pi
  import matplotlib.pyplot as plt
  
  from robot_arm import RobotArm
  from plotting import path_figure
  
  class TestPlotting(unittest.TestCase):
      def setUp(self):
          lengths = (3, 2, 2,)
          destinations = (
              (5, 4, 6, 4, 5),
              (0, 2, 0.5, -2, -1),
          )
          theta = (pi, pi / 2, 0,)
          self.robot_arm = RobotArm(
              lengths=lengths,
              destinations=destinations,
              theta=theta
          )
          n = len(lengths)
          s = len(destinations[0])
          total_joints = n * s
          self.theta_matrix = np.arange(total_joints).reshape((n, s))
  
      def test_plot_pure_functon(self):
          # Save values before function invocation
          original_destinations = self.robot_arm.destinations.copy()
          original_theta_matrix = self.theta_matrix.copy()
  
          # Run the pure function
          path_figure(self.theta_matrix, self.robot_arm, show=False)
  
          # Assert that none of the arguments have been changed
          np.testing.assert_array_equal(original_destinations, self.robot_arm.destinations)
          np.testing.assert_array_equal(original_theta_matrix, self.theta_matrix)
  
new_contents: import unittest
  import numpy as np
  
  from plotting import path_figure
  from fixtures import robot_arm1
  
  class TestPlotting(unittest.TestCase):
      def setUp(self):
          self.robot_arm = robot_arm1
          n = len(self.robot_arm.lengths)
          s = len(self.robot_arm.destinations[0])
          total_joints = n * s
          self.theta_matrix = np.arange(total_joints).reshape((n, s))
  
      def test_plot_pure_functon(self):
          # Save values before function invocation
          original_destinations = self.robot_arm.destinations.copy()
          original_theta_matrix = self.theta_matrix.copy()
  
          # Run the pure function
          path_figure(self.theta_matrix, self.robot_arm, show=False)
  
          # Assert that none of the arguments have been changed
          np.testing.assert_array_equal(original_destinations, self.robot_arm.destinations)
          np.testing.assert_array_equal(original_theta_matrix, self.theta_matrix)
  
subject: Use fixture for robot_arm test