use dostring_wrapper class

Author: jreback

pandas/core/frame.py

@@ -78,7 +78,7 @@
 from pandas import compat
 from pandas.compat.numpy import function as nv
 from pandas.util.decorators import (deprecate_kwarg, Appender,
-                                    Substitution, generate_dynamic_docstring)
+                                    Substitution, docstring_wrapper)
 from pandas.util.validators import validate_bool_kwarg
 
 from pandas.tseries.period import PeriodIndex
@@ -945,7 +945,7 @@ def to_gbq(self, destination_table, project_id, chunksize=10000,
     def _f():
         from pandas.io import gbq
         return gbq.to_gbq.__doc__
-    to_gbq.__doc__ = generate_dynamic_docstring(_f)
+    to_gbq = docstring_wrapper(to_gbq, _f)
 
     @classmethod
     def from_records(cls, data, index=None, exclude=None, columns=None,

pandas/io/gbq.py

@@ -1,6 +1,6 @@
 """ Google BigQuery support """
 
-from pandas.util.decorators import generate_dynamic_docstring
+from pandas.util.decorators import docstring_wrapper
 
 
 def _try_import():
@@ -31,8 +31,7 @@ def read_gbq(query, project_id=None, index_col=None, col_order=None,
         **kwargs)
 
 
-read_gbq.__doc__ = generate_dynamic_docstring(
-    lambda: _try_import().read_gbq.__doc__)
+read_gbq = docstring_wrapper(read_gbq, lambda: _try_import().read_gbq.__doc__)
 
 
 def to_gbq(dataframe, destination_table, project_id, chunksize=10000,
@@ -44,5 +43,4 @@ def to_gbq(dataframe, destination_table, project_id, chunksize=10000,
                       if_exists=if_exists, private_key=private_key)
 
 
-to_gbq.__doc__ = generate_dynamic_docstring(
-    lambda: _try_import().to_gbq.__doc__)
+to_gbq = docstring_wrapper(to_gbq, lambda: _try_import().to_gbq.__doc__)

pandas/util/decorators.py

@@ -3,7 +3,7 @@
 import sys
 import warnings
 from textwrap import dedent
-from functools import wraps
+from functools import wraps, update_wrapper
 
 
 def deprecate(name, alternative, alt_name=None):
@@ -235,22 +235,20 @@ def make_signature(func):
     return args, spec.args
 
 
-def generate_dynamic_docstring(creator):
-    """
-    this function returns a dynamically generated doc-string
-    that will call the creator callable to actually
-    create the docstring.
-
-    The point of this is that we want to get a docstring
-    from another module, but don't want to actually
-    import that module until we look up the docstring
-    rather than at function definition time
-    """
+class docstring_wrapper(object):
+    """ wrap a function, provide a dynamically evaluated doc-string """
 
-    class Docstring(str):
+    def __init__(self, func, creator):
+        self.func = func
+        self.creator = creator
+        update_wrapper(
+            self, func, ['__module__', '__name__',
+                         '__qualname__', '__annotations__'])
 
-        @staticmethod
-        def expandtabs(*args):
-            return creator().expandtabs(*args)
+    def __call__(*args, **kwargs):
+        self = args[0]
+        return self.func(*args[1:], **kwargs)
 
-    return Docstring()
+    @property
+    def __doc__(self):
+        return self.creator()