old_contents: import os, sys
  import dem
  import unittest
  import matplotlib
  import matplotlib.pyplot as plt
  #from matplotlib.testing.decorators import image_comparison
  import numpy as np
  import filecmp
  
  TESTDATA_FILENAME = os.path.join(os.path.dirname(__file__), 'data/big_basin.tif')
  
  
  class CalculationMethodsTestCase(unittest.TestCase):
      
      
      def setUp(self):
          
          self.dem = dem.DEMGrid(TESTDATA_FILENAME)
  
      def test_calculate_slope(self):
  
          sx, sy = self.dem._calculate_slope()
  
      def test_calculate_laplacian(self):
  
          del2z = self.dem._calculate_laplacian()
      
      def test_calculate_directional_laplacian(self):
          
          alpha = np.pi/4
          del2z = self.dem._calculate_directional_laplacian(alpha)
  
      def test_pad_boundary(self):
          
          dx = 5
          dy = 5
          grid = self.dem._griddata
  
          pad_x = np.zeros((self.dem._georef_info.ny, np.round(dx/2)))
          pad_y = np.zeros((np.round(dy/2), self.dem._georef_info.nx + 2*np.round(dx/2)))
          padded_grid = np.vstack([pad_y, np.hstack([pad_x, self.dem._griddata, pad_x]), pad_y])
          
          self.dem._pad_boundary(dx, dy)
          
          self.assertEqual(self.dem._griddata.all(), padded_grid.all(), 'Grid padded incorrectly')
  
  
  class BaseSpatialGridTestCase(unittest.TestCase):
  
  
      def setUp(self):
  
          self.dem = dem.BaseSpatialGrid(TESTDATA_FILENAME)
  
      #@image_comparison(baseline_images=['plot_gist_earth'], extensions=['png'])
      def test_plot(self):
  
          self.dem.plot(cmap='gist_earth')
  
      def test_save(self):
          
          self.dem.save('test.tif')
          
          this_file = os.path.join(os.path.dirname(__file__), 'test.tif')
          test_file = TESTDATA_FILENAME
  
          self.assertTrue(filecmp.cmp(this_file, test_file, shallow=False), 'GeoTIFF saved incorrectly')
  
  if __name__ == "__main__":
      unittest.main()
  
new_contents: import os, sys
  import dem
  import unittest
  import matplotlib
  import matplotlib.pyplot as plt
  #from matplotlib.testing.decorators import image_comparison
  import numpy as np
  import filecmp
  
  TESTDATA_FILENAME = os.path.join(os.path.dirname(__file__), 'data/big_basin.tif')
  
  
  class CalculationMethodsTestCase(unittest.TestCase):
      
      
      def setUp(self):
          
          self.dem = dem.DEMGrid(TESTDATA_FILENAME)
  
      def test_calculate_slope(self):
  
          sx, sy = self.dem._calculate_slope()
  
      def test_calculate_laplacian(self):
  
          del2z = self.dem._calculate_laplacian()
      
      def test_calculate_directional_laplacian(self):
          
          alpha = np.pi/4
          del2z = self.dem._calculate_directional_laplacian(alpha)
  
      def test_pad_boundary(self):
          
          dx = 5
          dy = 5
          grid = self.dem._griddata
  
          pad_x = np.zeros((self.dem._georef_info.ny, np.round(dx/2)))
          pad_y = np.zeros((np.round(dy/2), self.dem._georef_info.nx + 2*np.round(dx/2)))
          padded_grid = np.vstack([pad_y, np.hstack([pad_x, self.dem._griddata, pad_x]), pad_y])
          
          self.dem._pad_boundary(dx, dy)
          
          self.assertEqual(self.dem._griddata.all(), padded_grid.all(), 'Grid padded incorrectly')
  
  
  class BaseSpatialGridTestCase(unittest.TestCase):
  
  
      def setUp(self):
  
          self.dem = dem.BaseSpatialGrid(TESTDATA_FILENAME)
  
      #@image_comparison(baseline_images=['plot_gist_earth'], extensions=['png'])
      def test_plot(self):
  
          self.dem.plot(cmap='gist_earth')
  
      def test_save(self):
          
          this_file = os.path.join(os.path.dirname(__file__), 'data/big_basin_test.tif')
          test_file = TESTDATA_FILENAME
          
          self.dem.save(this_file)
  
          self.assertTrue(filecmp.cmp(this_file, test_file, shallow=False), 'GeoTIFF saved incorrectly')
  
  if __name__ == "__main__":
      unittest.main()
  
subject: Fix test file path