FutureWarning -> DeprecationWarning

Author: TomAugspurger

pandas/core/arrays/base.py

@@ -45,11 +45,6 @@ class ExtensionArray(StringMixin):
     * copy
     * _concat_same_type
 
-    An additional method is available to satisfy pandas' internal,
-    private block API.
-
-    * _formatting_values
-
     A default repr displaying the type, (truncated) data, length,
     and dtype is provided. It can be customized or replaced by
     by overriding:

pandas/core/internals/blocks.py

@@ -1960,7 +1960,7 @@ def formatting_values(self):
                 "'ExtensionArray._formatting_values' is deprecated. "
                 "Specify 'ExtensionArray._formatter' instead."
             )
-            warnings.warn(msg, FutureWarning, stacklevel=10)
+            warnings.warn(msg, DeprecationWarning, stacklevel=10)
             return self.values._formatting_values()
 
         return self.values

pandas/tests/extension/decimal/test_decimal.py

@@ -396,6 +396,6 @@ def _formatting_values(self):
     # different levels for 2 vs. 3
     check_stacklevel = compat.PY3
 
-    with tm.assert_produces_warning(FutureWarning,
+    with tm.assert_produces_warning(DeprecationWarning,
                                     check_stacklevel=check_stacklevel):
         repr(ser)