RF+TST: deprecate get_affine method of image

Thanks to Chris M for reminding me.

Author: matthew-brett

nibabel/spatialimages.py

@@ -627,11 +627,12 @@ def get_data_dtype(self):
     def set_data_dtype(self, dtype):
         self._header.set_data_dtype(dtype)
 
+    @deprecate_with_version('get_affine method is deprecated.\n'
+                            'Please use the ``img.affine`` property '
+                            'instead.',
+                            '2.1', '4.0')
     def get_affine(self):
         """ Get affine from image
-
-        Please use the `affine` property instead of `get_affine`; we will
-        deprecate this method in future versions of nibabel.
         """
         return self.affine
 

nibabel/tests/test_image_api.py

@@ -113,11 +113,14 @@ def validate_affine(self, imaker, params):
     def validate_affine_deprecated(self, imaker, params):
         # Check deprecated affine API
         img = imaker()
-        assert_almost_equal(img.get_affine(), params['affine'], 6)
-        assert_equal(img.get_affine().dtype, np.float64)
-        aff = img.get_affine()
-        aff[0, 0] = 1.5
-        assert_true(aff is img.get_affine())
+        with clear_and_catch_warnings() as w:
+            warnings.simplefilter('always', DeprecationWarning)
+            assert_almost_equal(img.get_affine(), params['affine'], 6)
+            assert_equal(len(w), 1)
+            assert_equal(img.get_affine().dtype, np.float64)
+            aff = img.get_affine()
+            aff[0, 0] = 1.5
+            assert_true(aff is img.get_affine())
 
     def validate_header(self, imaker, params):
         # Check header API
@@ -134,9 +137,9 @@ def validate_header(self, imaker, params):
 
     def validate_header_deprecated(self, imaker, params):
         # Check deprecated header API
+        img = imaker()
         with clear_and_catch_warnings() as w:
             warnings.simplefilter('always', DeprecationWarning)
-            img = imaker()
             hdr = img.get_header()
             assert_equal(len(w), 1)
             assert_true(hdr is img.header)