Deprecate unused features of normalize_kwargs.

anntzer · anntzer · commit 498f41d68126 · 2020-01-13T07:03:48.000+01:00
The required, forbidden and allowed kwargs of normalize_kwargs have
never been used and add a significant amount of complexity to the
implementation of normalize kwargs, so get rid of them.
diff --git a/doc/api/next_api_changes/deprecations.rst b/doc/api/next_api_changes/deprecations.rst
@@ -159,3 +159,7 @@ e.g. `.FuncFormatter`.
 ``OldAutoLocator``
 ~~~~~~~~~~~~~~~~~~
 This ticker is deprecated.
+
+*required*, *forbidden* and *allowed* parameters of `.cbook.normalize_kwargs`
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+These parameters are deprecated.
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -3881,8 +3881,7 @@ def line_props_with_rcdefaults(subkey, explicit, zdelta=0,
             if not use_marker:
                 d['marker'] = ''
             if explicit is not None:
-                d.update(
-                    cbook.normalize_kwargs(explicit, mlines.Line2D._alias_map))
+                d.update(cbook.normalize_kwargs(explicit, mlines.Line2D))
             return d
 
         # box properties
@@ -3897,8 +3896,7 @@ def line_props_with_rcdefaults(subkey, explicit, zdelta=0,
             )
             if boxprops is not None:
                 final_boxprops.update(
-                    cbook.normalize_kwargs(
-                        boxprops, mpatches.PathPatch._alias_map))
+                    cbook.normalize_kwargs(boxprops, mpatches.PathPatch))
         else:
             final_boxprops = line_props_with_rcdefaults('boxprops', boxprops,
                                                         use_marker=False)
diff --git a/lib/matplotlib/cbook/__init__.py b/lib/matplotlib/cbook/__init__.py
@@ -1682,6 +1682,9 @@ def sanitize_sequence(data):
             else data)
 
 
+@_delete_parameter("3.3", "required")
+@_delete_parameter("3.3", "forbidden")
+@_delete_parameter("3.3", "allowed")
 def normalize_kwargs(kw, alias_mapping=None, required=(), forbidden=(),
                      allowed=None):
     """
@@ -1713,16 +1716,16 @@ def normalize_kwargs(kw, alias_mapping=None, required=(), forbidden=(),
         mapping.
 
     required : list of str, optional
-        A list of keys that must be in *kws*.
+        A list of keys that must be in *kws*.  This parameter is deprecated.
 
     forbidden : list of str, optional
-        A list of keys which may not be in *kw*.
+        A list of keys which may not be in *kw*.  This parameter is deprecated.
 
     allowed : list of str, optional
         A list of allowed fields.  If this not None, then raise if
         *kw* contains any keys not in the union of *required*
         and *allowed*.  To allow only the required fields pass in
-        an empty tuple ``allowed=()``.
+        an empty tuple ``allowed=()``.  This parameter is deprecated.
 
     Raises
     ------
diff --git a/lib/matplotlib/tests/test_cbook.py b/lib/matplotlib/tests/test_cbook.py
@@ -1,7 +1,6 @@
 import itertools
 import pickle
 from weakref import ref
-import warnings
 from unittest.mock import patch, Mock
 
 from datetime import datetime
@@ -329,17 +328,17 @@ def test_sanitize_sequence():
 
 @pytest.mark.parametrize('inp, kwargs_to_norm', fail_mapping)
 def test_normalize_kwargs_fail(inp, kwargs_to_norm):
-    with pytest.raises(TypeError):
+    with pytest.raises(TypeError), \
+         cbook._suppress_matplotlib_deprecation_warning():
         cbook.normalize_kwargs(inp, **kwargs_to_norm)
 
 
 @pytest.mark.parametrize('inp, expected, kwargs_to_norm',
                          pass_mapping)
-def test_normalize_kwargs_pass(inp, expected, kwargs_to_norm):
-    with warnings.catch_warnings(record=True) as w:
-        warnings.simplefilter("always")
+def test_normalize_kwargs_pass(inp, expected, kwargs_to_norm, recwarn):
+    with cbook._suppress_matplotlib_deprecation_warning():
         assert expected == cbook.normalize_kwargs(inp, **kwargs_to_norm)
-        assert len(w) == 0
+    assert len(recwarn) == 0
 
 
 def test_warn_external_frame_embedded_python():
