COMPAT: silence mpl_style warnings

closes #12311
closes #12315

WARN: remove warnings from categorical tests with .str.extract

Author: jreback

pandas/core/config.py

@@ -127,7 +127,11 @@ def _set_option(*args, **kwargs):
         root[k] = v
 
         if o.cb:
-            o.cb(key)
+            if silent:
+                with warnings.catch_warnings(record=True):
+                    o.cb(key)
+            else:
+                o.cb(key)
 
 
 def _describe_option(pat='', _print_desc=True):

pandas/core/config_init.py

@@ -253,7 +253,7 @@
 
 def mpl_style_cb(key):
     warnings.warn(pc_mpl_style_deprecation_warning, FutureWarning,
-                  stacklevel=4)
+                  stacklevel=5)
 
     import sys
     from pandas.tools.plotting import mpl_stylesheet

pandas/tests/test_categorical.py

@@ -4109,7 +4109,8 @@ def test_str_accessor_api_for_categorical(self):
             ('decode', ("UTF-8",), {}),
             ('encode', ("UTF-8",), {}),
             ('endswith', ("a",), {}),
-            ('extract', ("([a-z]*) ",), {}),
+            ('extract', ("([a-z]*) ",), {"expand":False}),
+            ('extract', ("([a-z]*) ",), {"expand":True}),
             ('extractall', ("([a-z]*) ",), {}),
             ('find', ("a",), {}),
             ('findall', ("a",), {}),