root / lib / objectutils.py @ 503574ec
History | View | Annotate | Download (2.5 kB)
1 |
#
|
---|---|
2 |
#
|
3 |
|
4 |
# Copyright (C) 2012 Google Inc.
|
5 |
#
|
6 |
# This program is free software; you can redistribute it and/or modify
|
7 |
# it under the terms of the GNU General Public License as published by
|
8 |
# the Free Software Foundation; either version 2 of the License, or
|
9 |
# (at your option) any later version.
|
10 |
#
|
11 |
# This program is distributed in the hope that it will be useful, but
|
12 |
# WITHOUT ANY WARRANTY; without even the implied warranty of
|
13 |
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
14 |
# General Public License for more details.
|
15 |
#
|
16 |
# You should have received a copy of the GNU General Public License
|
17 |
# along with this program; if not, write to the Free Software
|
18 |
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
19 |
# 02110-1301, USA.
|
20 |
|
21 |
"""Module for object related utils."""
|
22 |
|
23 |
|
24 |
class AutoSlots(type): |
25 |
"""Meta base class for __slots__ definitions.
|
26 |
|
27 |
"""
|
28 |
def __new__(mcs, name, bases, attrs): |
29 |
"""Called when a class should be created.
|
30 |
|
31 |
@param mcs: The meta class
|
32 |
@param name: Name of created class
|
33 |
@param bases: Base classes
|
34 |
@type attrs: dict
|
35 |
@param attrs: Class attributes
|
36 |
|
37 |
"""
|
38 |
assert "__slots__" not in attrs, \ |
39 |
"Class '%s' defines __slots__ when it should not" % name
|
40 |
|
41 |
attrs["__slots__"] = mcs._GetSlots(attrs)
|
42 |
|
43 |
return type.__new__(mcs, name, bases, attrs) |
44 |
|
45 |
@classmethod
|
46 |
def _GetSlots(mcs, attrs): |
47 |
"""Used to get the list of defined slots.
|
48 |
|
49 |
@param attrs: The attributes of the class
|
50 |
|
51 |
"""
|
52 |
raise NotImplementedError |
53 |
|
54 |
|
55 |
class ValidatedSlots(object): |
56 |
"""Sets and validates slots.
|
57 |
|
58 |
"""
|
59 |
__slots__ = [] |
60 |
|
61 |
def __init__(self, **kwargs): |
62 |
"""Constructor for BaseOpCode.
|
63 |
|
64 |
The constructor takes only keyword arguments and will set
|
65 |
attributes on this object based on the passed arguments. As such,
|
66 |
it means that you should not pass arguments which are not in the
|
67 |
__slots__ attribute for this class.
|
68 |
|
69 |
"""
|
70 |
slots = self.GetAllSlots()
|
71 |
for (key, value) in kwargs.items(): |
72 |
if key not in slots: |
73 |
raise TypeError("Object %s doesn't support the parameter '%s'" % |
74 |
(self.__class__.__name__, key))
|
75 |
setattr(self, key, value) |
76 |
|
77 |
@classmethod
|
78 |
def GetAllSlots(cls): |
79 |
"""Compute the list of all declared slots for a class.
|
80 |
|
81 |
"""
|
82 |
slots = [] |
83 |
for parent in cls.__mro__: |
84 |
slots.extend(getattr(parent, "__slots__", [])) |
85 |
return slots
|
86 |
|
87 |
def Validate(self): |
88 |
"""Validates the slots.
|
89 |
|
90 |
This method must be implemented by the child classes.
|
91 |
|
92 |
"""
|
93 |
raise NotImplementedError |