1
# Copyright (C) 2006, 2007 Canonical Ltd
2
# Authors: Robert Collins <robert.collins@canonical.com> and others
4
# This program is free software; you can redistribute it and/or modify
5
# it under the terms of the GNU General Public License as published by
6
# the Free Software Foundation; either version 2 of the License, or
7
# (at your option) any later version.
9
# This program is distributed in the hope that it will be useful,
10
# but WITHOUT ANY WARRANTY; without even the implied warranty of
11
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12
# GNU General Public License for more details.
14
# You should have received a copy of the GNU General Public License
15
# along with this program; if not, write to the Free Software
16
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20
The methods here allow for api symbol versioning.
23
__all__ = ['deprecated_function',
26
'DEPRECATED_PARAMETER',
28
'warn', 'set_warning_method', 'zero_seven',
43
from warnings import warn
46
DEPRECATED_PARAMETER = "A deprecated parameter marker."
47
zero_seven = "%s was deprecated in version 0.7."
48
zero_eight = "%s was deprecated in version 0.8."
49
zero_nine = "%s was deprecated in version 0.9."
50
zero_ten = "%s was deprecated in version 0.10."
51
zero_eleven = "%s was deprecated in version 0.11."
52
zero_twelve = "%s was deprecated in version 0.12."
53
zero_thirteen = "%s was deprecated in version 0.13."
54
zero_fourteen = "%s was deprecated in version 0.14."
55
zero_fifteen = "%s was deprecated in version 0.15."
56
zero_sixteen = "%s was deprecated in version 0.16."
57
zero_seventeen = "%s was deprecated in version 0.17."
58
zero_eighteen = "%s was deprecated in version 0.18."
59
zero_nineteen = "%s was deprecated in version 0.19."
62
def set_warning_method(method):
63
"""Set the warning method to be used by this module.
65
It should take a message and a warning category as warnings.warn does.
71
# TODO - maybe this would be easier to use as one 'smart' method that
72
# guess if it is a method or a class or an attribute ? If so, we can
73
# add that on top of the primitives, once we have all three written
77
def deprecation_string(a_callable, deprecation_version):
78
"""Generate an automatic deprecation string for a_callable.
80
:param a_callable: The callable to substitute into deprecation_version.
81
:param deprecation_version: A deprecation format warning string. This should
82
have a single %s operator in it. a_callable will be turned into a nice
83
python symbol and then substituted into deprecation_version.
85
if getattr(a_callable, 'im_class', None) is None:
86
symbol = "%s.%s" % (a_callable.__module__,
89
symbol = "%s.%s.%s" % (a_callable.im_class.__module__,
90
a_callable.im_class.__name__,
93
return deprecation_version % symbol
96
def deprecated_function(deprecation_version):
97
"""Decorate a function so that use of it will trigger a warning."""
99
def function_decorator(callable):
100
"""This is the function python calls to perform the decoration."""
102
def decorated_function(*args, **kwargs):
103
"""This is the decorated function."""
104
warn(deprecation_string(callable, deprecation_version),
105
DeprecationWarning, stacklevel=2)
106
return callable(*args, **kwargs)
107
_populate_decorated(callable, deprecation_version, "function",
109
return decorated_function
110
return function_decorator
113
def deprecated_method(deprecation_version):
114
"""Decorate a method so that use of it will trigger a warning.
116
To deprecate an entire class, decorate __init__.
119
def method_decorator(callable):
120
"""This is the function python calls to perform the decoration."""
122
def decorated_method(self, *args, **kwargs):
123
"""This is the decorated method."""
124
symbol = "%s.%s.%s" % (self.__class__.__module__,
125
self.__class__.__name__,
128
warn(deprecation_version % symbol, DeprecationWarning, stacklevel=2)
129
return callable(self, *args, **kwargs)
130
_populate_decorated(callable, deprecation_version, "method",
132
return decorated_method
133
return method_decorator
136
def deprecated_passed(parameter_value):
137
"""Return True if parameter_value was used."""
138
# FIXME: it might be nice to have a parameter deprecation decorator.
139
# it would need to handle positional and *args and **kwargs parameters,
140
# which means some mechanism to describe how the parameter was being
141
# passed before deprecation, and some way to deprecate parameters that
142
# were not at the end of the arg list. Thats needed for __init__ where
143
# we cannot just forward to a new method name.I.e. in the following
144
# examples we would want to have callers that pass any value to 'bad' be
145
# given a warning - because we have applied:
146
# @deprecated_parameter('bad', zero_seven)
148
# def __init__(self, bad=None)
149
# def __init__(self, bad, other)
150
# def __init__(self, **kwargs)
152
return not parameter_value is DEPRECATED_PARAMETER
155
def _decorate_docstring(callable, deprecation_version, label,
158
docstring_lines = callable.__doc__.split('\n')
161
if len(docstring_lines) == 0:
162
decorated_callable.__doc__ = deprecation_version % ("This " + label)
163
elif len(docstring_lines) == 1:
164
decorated_callable.__doc__ = (callable.__doc__
167
+ deprecation_version % ("This " + label)
170
spaces = len(docstring_lines[-1])
171
new_doc = callable.__doc__
172
new_doc += "\n" + " " * spaces
173
new_doc += deprecation_version % ("This " + label)
174
new_doc += "\n" + " " * spaces
175
decorated_callable.__doc__ = new_doc
178
def _populate_decorated(callable, deprecation_version, label,
180
"""Populate attributes like __name__ and __doc__ on the decorated callable.
182
_decorate_docstring(callable, deprecation_version, label,
184
decorated_callable.__module__ = callable.__module__
185
decorated_callable.__name__ = callable.__name__
186
decorated_callable.is_deprecated = True
189
def _dict_deprecation_wrapper(wrapped_method):
190
"""Returns a closure that emits a warning and calls the superclass"""
191
def cb(dep_dict, *args, **kwargs):
192
msg = 'access to %s' % (dep_dict._variable_name, )
193
msg = dep_dict._deprecation_version % (msg,)
195
msg += ' ' + dep_dict._advice
196
warn(msg, DeprecationWarning, stacklevel=2)
197
return wrapped_method(dep_dict, *args, **kwargs)
201
class DeprecatedDict(dict):
202
"""A dictionary that complains when read or written."""
212
"""Create a dict that warns when read or modified.
214
:param deprecation_version: something like zero_nine
215
:param initial_value: The contents of the dict
216
:param variable_name: This allows better warnings to be printed
217
:param advice: String of advice on what callers should do instead
218
of using this variable.
220
self._deprecation_version = deprecation_version
221
self._variable_name = variable_name
222
self._advice = advice
223
dict.__init__(self, initial_value)
225
# This isn't every possible method but it should trap anyone using the
226
# dict -- add more if desired
227
__len__ = _dict_deprecation_wrapper(dict.__len__)
228
__getitem__ = _dict_deprecation_wrapper(dict.__getitem__)
229
__setitem__ = _dict_deprecation_wrapper(dict.__setitem__)
230
__delitem__ = _dict_deprecation_wrapper(dict.__delitem__)
231
keys = _dict_deprecation_wrapper(dict.keys)
232
__contains__ = _dict_deprecation_wrapper(dict.__contains__)
235
def deprecated_list(deprecation_version, variable_name,
236
initial_value, extra=None):
237
"""Create a list that warns when modified
239
:param deprecation_version: something like zero_nine
240
:param initial_value: The contents of the list
241
:param variable_name: This allows better warnings to be printed
242
:param extra: Extra info to print when printing a warning
245
subst_text = 'Modifying %s' % (variable_name,)
246
msg = deprecation_version % (subst_text,)
250
class _DeprecatedList(list):
251
__doc__ = list.__doc__ + msg
255
def _warn_deprecated(self, func, *args, **kwargs):
256
warn(msg, DeprecationWarning, stacklevel=3)
257
return func(self, *args, **kwargs)
259
def append(self, obj):
260
"""appending to %s is deprecated""" % (variable_name,)
261
return self._warn_deprecated(list.append, obj)
263
def insert(self, index, obj):
264
"""inserting to %s is deprecated""" % (variable_name,)
265
return self._warn_deprecated(list.insert, index, obj)
267
def extend(self, iterable):
268
"""extending %s is deprecated""" % (variable_name,)
269
return self._warn_deprecated(list.extend, iterable)
271
def remove(self, value):
272
"""removing from %s is deprecated""" % (variable_name,)
273
return self._warn_deprecated(list.remove, value)
275
def pop(self, index=None):
276
"""pop'ing from from %s is deprecated""" % (variable_name,)
278
return self._warn_deprecated(list.pop, index)
281
return self._warn_deprecated(list.pop)
283
return _DeprecatedList(initial_value)