Fix bogus no_op implementation

doc/source/composites.rst

@@ -579,8 +579,9 @@ the file) as::
    default apply the :func:`~trollimage.xrimage.XRImage.stretch_linear` enhancement with
    cutoffs of 0.5% and 99.5%.  If you want no enhancement at all (maybe you
    are enhancing a composite based on :class:`DayNightCompositor` where
-   the components have their own enhancements defined), you need to define
-   an enhancement that does nothing::
+   the components have their own enhancements defined), you can use the `image_ready` standard name.
+   If this is not a suitable standard name, you can also define
+   an enhancement that does nothing:
 
       enhancements:
         day_x:

satpy/enhancements/__init__.py

@@ -653,8 +653,3 @@ def _jma_true_color_reproduction(img_data, platform=None):
 
     output = da.dot(img_data.T, ccm.T)
     return output.T
-
-
-def no_op(img):
-    """Do not do anything to the image."""
-    return img.data

satpy/etc/enhancements/generic.yaml

@@ -1288,6 +1288,4 @@ enhancements:
 
   image_ready:
     standard_name: image_ready
-    operations:
-      - name: no_op
-        method: !!python/name:satpy.enhancements.no_op
+    operations: []

satpy/tests/enhancement_tests/test_enhancements.py

@@ -711,15 +711,3 @@ def test_jma_true_color_reproduction(self):
         img = XRImage(self.rgb)
         with pytest.raises(KeyError, match="No conversion matrix found for platform Fakesat"):
             jma_true_color_reproduction(img)
-
-
-def test_no_op_enhancement():
-    """Test the no-op enhancement."""
-    from satpy.enhancements import no_op
-
-    data = da.arange(-100, 1000, 110).reshape(2, 5)
-    rgb_data = np.stack([data, data, data])
-    rgb = xr.DataArray(rgb_data, dims=("bands", "y", "x"),
-                       coords={"bands": ["R", "G", "B"]},
-                       attrs={"platform_name": "Himawari-8"})
-    assert no_op(rgb) is rgb.data