Separate some tool tests

Author: uvchik

tests/test_tools.py

@@ -7,38 +7,57 @@
 
 class TestTools:
 
-    def test_linear_interpolation_extrapolation(self):
-        parameters = {'target_height': 80}
-        df = pd.DataFrame(data={10: [2.0, 2.0, 3.0],
-                                80: [4.0, 5.0, 6.0],
-                                200: [5.0, 8.0, 10.0]},
-                          index=[0, 1, 2])
-        # target_height is equal to height given in a column of the DataFrame
+    @classmethod
+    def setup_class(cls):
+        cls.parameters = {'target_height': 80}
+        cls.df = pd.DataFrame(data={10: [2.0, 2.0, 3.0],
+                                    80: [4.0, 5.0, 6.0],
+                                    200: [5.0, 8.0, 10.0]},
+                              index=[0, 1, 2])
+
+    def test_linear_target_height_is_equal_to_given_height(self):
+        """
+        Test linear interpolation and extrapolation if target_height is equal
+        to height given in a column of the DataFrame.
+        """
         exp_output = pd.Series(data=[4.0, 5.0, 6.0])
         assert_series_equal(linear_interpolation_extrapolation(
-            df, **parameters), exp_output)
-        # target_height is between heights given in the columns of the
-        # DataFrame
+            self.df, **self.parameters), exp_output)
+
+    def test_linear_target_height_is_between_given_heights(self):
+        """
+        Test linear interpolation and extrapolation if target_height is between
+        heights given in the columns of the DataFrame
+        """
         exp_output = pd.Series(data=[4.5, 6.5, 8.0])
-        parameters['target_height'] = 140
+        self.parameters['target_height'] = 140
         assert_series_equal(linear_interpolation_extrapolation(
-            df, **parameters), exp_output)
+            self.df, **self.parameters), exp_output)
+
         exp_output = pd.Series(data=[4.285714, 5.428571, 6.428571])
-        parameters['target_height'] = 90
+        self.parameters['target_height'] = 90
         assert_series_equal(linear_interpolation_extrapolation(
-            df, **parameters), exp_output)
-        # target_height is greater than the heights given in the columns of the
-        # DataFrame
+            self.df, **self.parameters), exp_output)
+
+    def test_linear_target_height_is_greater_than_the_given_heights(self):
+        """
+        Test linear interpolation and extrapolation if target_height is greater
+        than the heights given in the columns of the DataFrame
+        """
         exp_output = pd.Series(data=[5.333333, 9.0, 11.333333])
-        parameters['target_height'] = 240
+        self.parameters['target_height'] = 240
         assert_series_equal(linear_interpolation_extrapolation(
-            df, **parameters), exp_output)
-        # target_height is smaller than the heights given in the columns of the
-        # DataFrame
+            self.df, **self.parameters), exp_output)
+
+    def test_linear_target_height_is_smaller_than_the_given_heights(self):
+        """
+        Test linear interpolation and extrapolation if target_height is smaller
+        than the heights given in the columns of the DataFrame
+        """
         exp_output = pd.Series(data=[1.857143, 1.785714, 2.785714])
-        parameters['target_height'] = 5
+        self.parameters['target_height'] = 5
         assert_series_equal(linear_interpolation_extrapolation(
-            df, **parameters), exp_output)
+            self.df, **self.parameters), exp_output)
 
     def test_logarithmic_interpolation_extrapolation(self):
         parameters = {'target_height': 80}