add docstring for unit tests

tests/test_flip_image.py

@@ -9,7 +9,19 @@ from csst_proto import flip_multiple_images_jl, flip_multiple_images_mp
 
 class FlipImageTestCase(unittest.TestCase):
     def test_flip_image(self):
-        """test flip image"""
+        """
+        Aim
+        ---
+        Test `flip_image` function with package data.
+
+        Criteria
+        --------
+        The flipped image is consistent with answer.
+
+        Details
+        -------
+        The input image is in package data.
+        """
         self.assertTrue(
             np.all(flip_image(read_default_image()) == np.array([[4, 3], [2, 1]]))
         )
@@ -19,7 +31,19 @@ class FlipImageTestCase(unittest.TestCase):
             flip_image(np.array([1, 2, 3, 4]))
 
     def test_flip_image_on_server(self):
-        """test flip image on server"""
+        """
+        Aim
+        ---
+        Test `flip_image` function with server data.
+
+        Criteria
+        --------
+        The flipped image is consistent with answer at 1e-6 level.
+
+        Details
+        -------
+        This is the same case with `test_flip_image` but the data is on server.
+        """
         image_input = np.loadtxt(
             os.path.join(
                 os.environ["UNIT_TEST_DATA_ROOT"],
@@ -43,7 +67,19 @@ class FlipImageTestCase(unittest.TestCase):
         )
 
     def test_flip_multiple_images_mp(self):
-        """test flip multiple images with multiprocessing"""
+        """
+        Aim
+        ---
+        Test `flip_multiple_images_mp` function with package data.
+
+        Criteria
+        --------
+        The flipped image equals answer.
+
+        Details
+        -------
+        The input image is in package data.
+        """
         n_jobs = 10
         imgs = [read_default_image() for _ in range(n_jobs)]
         flipped_imgs = flip_multiple_images_mp(imgs, n_jobs)
@@ -51,7 +87,19 @@ class FlipImageTestCase(unittest.TestCase):
             self.assertTrue(np.all(flipped_imgs[i_job] == np.array([[4, 3], [2, 1]])))
 
     def test_flip_multiple_images_jl(self):
-        """test flip multiple images with joblib"""
+        """
+        Aim
+        ---
+        Test `flip_multiple_images_jl` function with package data.
+
+        Criteria
+        --------
+        The flipped image equals answer.
+
+        Details
+        -------
+        The input image is in package data.
+        """
         n_jobs = 10
         imgs = [read_default_image() for _ in range(n_jobs)]
         flipped_imgs = flip_multiple_images_jl(imgs, n_jobs)