Support for OO Optimization

doc/source/whatsnew/v0.23.1.txt

@@ -94,3 +94,8 @@ Categorical
 ^^^^^^^^^^^
 
 -
+
+Other
+^^^^^
+
+- Bug preventing pandas from being importable with -OO optimization (:issue:`21071`)

pandas/tests/test_downstream.py

@@ -2,6 +2,8 @@
 """
 Testing that we work in the downstream packages
 """
+import subprocess
+
 import pytest
 import numpy as np  # noqa
 from pandas import DataFrame
@@ -53,6 +55,11 @@ def test_xarray(df):
     assert df.to_xarray() is not None
 
 
+def test_oo_optimizable():
+    # GH 21071
+    subprocess.check_call(["python", "-OO", "-c", "import pandas"])
+
+
 @tm.network
 def test_statsmodels():
 

pandas/tseries/offsets.py

@@ -14,7 +14,7 @@
 # import after tools, dateutil check
 from dateutil.easter import easter
 from pandas._libs import tslib, Timestamp, OutOfBoundsDatetime, Timedelta
-from pandas.util._decorators import cache_readonly
+from pandas.util._decorators import cache_readonly, Appender, Substitution
 
 from pandas._libs.tslibs import ccalendar, frequencies as libfrequencies
 from pandas._libs.tslibs.timedeltas import delta_to_nanoseconds
@@ -1011,7 +1011,7 @@ class BusinessMonthBegin(MonthOffset):
 class _CustomBusinessMonth(_CustomMixin, BusinessMixin, MonthOffset):
     """
     DateOffset subclass representing one custom business month, incrementing
-    between [BEGIN/END] of month dates
+    between %(increment)s of month dates
 
     Parameters
     ----------
@@ -1089,13 +1089,15 @@ def apply(self, other):
         return result
 
 
+@Substitution(increment='end')
+@Appender(_CustomBusinessMonth.__doc__)
 class CustomBusinessMonthEnd(_CustomBusinessMonth):
-    __doc__ = _CustomBusinessMonth.__doc__.replace('[BEGIN/END]', 'end')
     _prefix = 'CBM'
 
 
+@Substitution(increment='beginning')
+@Appender(_CustomBusinessMonth.__doc__)
 class CustomBusinessMonthBegin(_CustomBusinessMonth):
-    __doc__ = _CustomBusinessMonth.__doc__.replace('[BEGIN/END]', 'beginning')
     _prefix = 'CBMS'
 
 

pandas/util/_decorators.py

@@ -3,7 +3,7 @@
 import inspect
 import types
 import warnings
-from textwrap import dedent, wrap
+from textwrap import dedent
 from functools import wraps, update_wrapper
 
 
@@ -19,46 +19,42 @@ def deprecate(name, alternative, version, alt_name=None,
 
     Parameters
     ----------
-    name : str
-        Name of function to deprecate
-    alternative : str
-        Name of function to use instead
+    name : func
+        Function to deprecate.
+    alternative : func
+        Function to use instead.
     version : str
-        Version of pandas in which the method has been deprecated
+        Version of pandas in which the method has been deprecated.
     alt_name : str, optional
-        Name to use in preference of alternative.__name__
+        Name to use in preference of alternative.__name__.
     klass : Warning, default FutureWarning
     stacklevel : int, default 2
     msg : str
-          The message to display in the warning.
-          Default is '{name} is deprecated. Use {alt_name} instead.'
+        The message to display in the warning.
+        Default is '{name} is deprecated. Use {alt_name} instead.'
     """
 
     alt_name = alt_name or alternative.__name__
     klass = klass or FutureWarning
     warning_msg = msg or '{} is deprecated, use {} instead'.format(name,
                                                                    alt_name)
 
+    # adding deprecated directive to the docstring
+    msg = msg or 'Use `{alt_name}` instead.'.format(alt_name=alt_name)
+
+    @Substitution(version=version, msg=msg)
+    @Appender(name.__doc__)
     @wraps(alternative)
     def wrapper(*args, **kwargs):
+        """
+        .. deprecated:: %(version)s
+
+           %(msg)s
+
+        """
         warnings.warn(warning_msg, klass, stacklevel=stacklevel)
         return alternative(*args, **kwargs)
 
-    # adding deprecated directive to the docstring
-    msg = msg or 'Use `{alt_name}` instead.'.format(alt_name=alt_name)
-    tpl = dedent("""
-    .. deprecated:: {version}
-
-       {msg}
-
-    {rest}
-    """)
-    rest = getattr(wrapper, '__doc__', '')
-    docstring = tpl.format(version=version,
-                           msg='\n    '.join(wrap(msg, 70)),
-                           rest=dedent(rest))
-    wrapper.__doc__ = docstring
-
     return wrapper