Deprecate passing kwargs to Shadow

timhoffm · timhoffm · commit 463125cc302b · 2020-01-04T22:48:25.000+01:00
diff --git a/doc/api/next_api_changes/deprecations.rst b/doc/api/next_api_changes/deprecations.rst
@@ -106,3 +106,9 @@ Likewise, passing the *alpha*, *boundaries*, *values*, *extend*, or *filled*
 parameters with a `.ContourSet` mappable, or the *alpha* parameter with an
 `.Artist` mappable, is deprecated, as the mappable would likewise override
 them.
+
+Unused parameters
+~~~~~~~~~~~~~~~~~
+The following parameters do not have any effect and are deprecated:
+
+- arbitrary keyword arguments to `Shadow`
diff --git a/lib/matplotlib/patches.py b/lib/matplotlib/patches.py
@@ -631,15 +631,25 @@ def __str__(self):
     @docstring.dedent_interpd
     def __init__(self, patch, ox, oy, props=None, **kwargs):
         """
-        Create a shadow of the given *patch* offset by *ox*, *oy*.
-        *props*, if not *None*, is a patch property update dictionary.
-        If *None*, the shadow will have have the same color as the face,
+        Create a shadow of the given *patch*.
+
+        By default, the shadow will have the same face color as the *patch*,
         but darkened.
 
-        Valid keyword arguments are:
+        Parameters
+        ----------
+        patch : `.Patch`
+            The patch to create the shadow for.
+        ox, oy : float
+            The shift of the shadow in points.
+        props : dict
+            Properties of the shadow patch. Supported keys are:
 
-        %(Patch)s
+            %(Patch)s
         """
+        if kwargs:
+            cbook.warn_deprecated(
+                "3.3", "Passing keyword arguments to Shadow is deprecated.")
         Patch.__init__(self)
         self.patch = patch
         self.props = props
