mirror of
https://git.yoctoproject.org/poky-contrib
synced 2025-05-08 23:52:25 +08:00
79834a7144
This adds the SPDX-License-Identifier license headers to the majority of our source files to make it clearer exactly which license files are under. The bulk of the files are under GPL v2.0 with one found to be under V2.0 or later, some under MIT and some have dual license. There are some files which are potentially harder to classify where we've imported upstream code and those can be handled specifically in later commits. The COPYING file is replaced with LICENSE.X files which contain the full license texts. (Bitbake rev: ff237c33337f4da2ca06c3a2c49699bc26608a6b) Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
259 lines
8.6 KiB
Python
259 lines
8.6 KiB
Python
# http://code.activestate.com/recipes/577629-namedtupleabc-abstract-base-class-mix-in-for-named/
|
|
#!/usr/bin/env python
|
|
# Copyright (c) 2011 Jan Kaliszewski (zuo). Available under the MIT License.
|
|
#
|
|
# SPDX-License-Identifier: MIT
|
|
#
|
|
|
|
"""
|
|
namedtuple_with_abc.py:
|
|
* named tuple mix-in + ABC (abstract base class) recipe,
|
|
* works under Python 2.6, 2.7 as well as 3.x.
|
|
|
|
Import this module to patch collections.namedtuple() factory function
|
|
-- enriching it with the 'abc' attribute (an abstract base class + mix-in
|
|
for named tuples) and decorating it with a wrapper that registers each
|
|
newly created named tuple as a subclass of namedtuple.abc.
|
|
|
|
How to import:
|
|
import collections, namedtuple_with_abc
|
|
or:
|
|
import namedtuple_with_abc
|
|
from collections import namedtuple
|
|
# ^ in this variant you must import namedtuple function
|
|
# *after* importing namedtuple_with_abc module
|
|
or simply:
|
|
from namedtuple_with_abc import namedtuple
|
|
|
|
Simple usage example:
|
|
class Credentials(namedtuple.abc):
|
|
_fields = 'username password'
|
|
def __str__(self):
|
|
return ('{0.__class__.__name__}'
|
|
'(username={0.username}, password=...)'.format(self))
|
|
print(Credentials("alice", "Alice's password"))
|
|
|
|
For more advanced examples -- see below the "if __name__ == '__main__':".
|
|
"""
|
|
|
|
import collections
|
|
from abc import ABCMeta, abstractproperty
|
|
from functools import wraps
|
|
from sys import version_info
|
|
|
|
__all__ = ('namedtuple',)
|
|
_namedtuple = collections.namedtuple
|
|
|
|
|
|
class _NamedTupleABCMeta(ABCMeta):
|
|
'''The metaclass for the abstract base class + mix-in for named tuples.'''
|
|
def __new__(mcls, name, bases, namespace):
|
|
fields = namespace.get('_fields')
|
|
for base in bases:
|
|
if fields is not None:
|
|
break
|
|
fields = getattr(base, '_fields', None)
|
|
if not isinstance(fields, abstractproperty):
|
|
basetuple = _namedtuple(name, fields)
|
|
bases = (basetuple,) + bases
|
|
namespace.pop('_fields', None)
|
|
namespace.setdefault('__doc__', basetuple.__doc__)
|
|
namespace.setdefault('__slots__', ())
|
|
return ABCMeta.__new__(mcls, name, bases, namespace)
|
|
|
|
|
|
exec(
|
|
# Python 2.x metaclass declaration syntax
|
|
"""class _NamedTupleABC(object):
|
|
'''The abstract base class + mix-in for named tuples.'''
|
|
__metaclass__ = _NamedTupleABCMeta
|
|
_fields = abstractproperty()""" if version_info[0] < 3 else
|
|
# Python 3.x metaclass declaration syntax
|
|
"""class _NamedTupleABC(metaclass=_NamedTupleABCMeta):
|
|
'''The abstract base class + mix-in for named tuples.'''
|
|
_fields = abstractproperty()"""
|
|
)
|
|
|
|
|
|
_namedtuple.abc = _NamedTupleABC
|
|
#_NamedTupleABC.register(type(version_info)) # (and similar, in the future...)
|
|
|
|
@wraps(_namedtuple)
|
|
def namedtuple(*args, **kwargs):
|
|
'''Named tuple factory with namedtuple.abc subclass registration.'''
|
|
cls = _namedtuple(*args, **kwargs)
|
|
_NamedTupleABC.register(cls)
|
|
return cls
|
|
|
|
collections.namedtuple = namedtuple
|
|
|
|
|
|
|
|
|
|
if __name__ == '__main__':
|
|
|
|
'''Examples and explanations'''
|
|
|
|
# Simple usage
|
|
|
|
class MyRecord(namedtuple.abc):
|
|
_fields = 'x y z' # such form will be transformed into ('x', 'y', 'z')
|
|
def _my_custom_method(self):
|
|
return list(self._asdict().items())
|
|
# (the '_fields' attribute belongs to the named tuple public API anyway)
|
|
|
|
rec = MyRecord(1, 2, 3)
|
|
print(rec)
|
|
print(rec._my_custom_method())
|
|
print(rec._replace(y=222))
|
|
print(rec._replace(y=222)._my_custom_method())
|
|
|
|
# Custom abstract classes...
|
|
|
|
class MyAbstractRecord(namedtuple.abc):
|
|
def _my_custom_method(self):
|
|
return list(self._asdict().items())
|
|
|
|
try:
|
|
MyAbstractRecord() # (abstract classes cannot be instantiated)
|
|
except TypeError as exc:
|
|
print(exc)
|
|
|
|
class AnotherAbstractRecord(MyAbstractRecord):
|
|
def __str__(self):
|
|
return '<<<{0}>>>'.format(super(AnotherAbstractRecord,
|
|
self).__str__())
|
|
|
|
# ...and their non-abstract subclasses
|
|
|
|
class MyRecord2(MyAbstractRecord):
|
|
_fields = 'a, b'
|
|
|
|
class MyRecord3(AnotherAbstractRecord):
|
|
_fields = 'p', 'q', 'r'
|
|
|
|
rec2 = MyRecord2('foo', 'bar')
|
|
print(rec2)
|
|
print(rec2._my_custom_method())
|
|
print(rec2._replace(b=222))
|
|
print(rec2._replace(b=222)._my_custom_method())
|
|
|
|
rec3 = MyRecord3('foo', 'bar', 'baz')
|
|
print(rec3)
|
|
print(rec3._my_custom_method())
|
|
print(rec3._replace(q=222))
|
|
print(rec3._replace(q=222)._my_custom_method())
|
|
|
|
# You can also subclass non-abstract ones...
|
|
|
|
class MyRecord33(MyRecord3):
|
|
def __str__(self):
|
|
return '< {0!r}, ..., {0!r} >'.format(self.p, self.r)
|
|
|
|
rec33 = MyRecord33('foo', 'bar', 'baz')
|
|
print(rec33)
|
|
print(rec33._my_custom_method())
|
|
print(rec33._replace(q=222))
|
|
print(rec33._replace(q=222)._my_custom_method())
|
|
|
|
# ...and even override the magic '_fields' attribute again
|
|
|
|
class MyRecord345(MyRecord3):
|
|
_fields = 'e f g h i j k'
|
|
|
|
rec345 = MyRecord345(1, 2, 3, 4, 3, 2, 1)
|
|
print(rec345)
|
|
print(rec345._my_custom_method())
|
|
print(rec345._replace(f=222))
|
|
print(rec345._replace(f=222)._my_custom_method())
|
|
|
|
# Mixing-in some other classes is also possible:
|
|
|
|
class MyMixIn(object):
|
|
def method(self):
|
|
return "MyMixIn.method() called"
|
|
def _my_custom_method(self):
|
|
return "MyMixIn._my_custom_method() called"
|
|
def count(self, item):
|
|
return "MyMixIn.count({0}) called".format(item)
|
|
def _asdict(self): # (cannot override a namedtuple method, see below)
|
|
return "MyMixIn._asdict() called"
|
|
|
|
class MyRecord4(MyRecord33, MyMixIn): # mix-in on the right
|
|
_fields = 'j k l x'
|
|
|
|
class MyRecord5(MyMixIn, MyRecord33): # mix-in on the left
|
|
_fields = 'j k l x y'
|
|
|
|
rec4 = MyRecord4(1, 2, 3, 2)
|
|
print(rec4)
|
|
print(rec4.method())
|
|
print(rec4._my_custom_method()) # MyRecord33's
|
|
print(rec4.count(2)) # tuple's
|
|
print(rec4._replace(k=222))
|
|
print(rec4._replace(k=222).method())
|
|
print(rec4._replace(k=222)._my_custom_method()) # MyRecord33's
|
|
print(rec4._replace(k=222).count(8)) # tuple's
|
|
|
|
rec5 = MyRecord5(1, 2, 3, 2, 1)
|
|
print(rec5)
|
|
print(rec5.method())
|
|
print(rec5._my_custom_method()) # MyMixIn's
|
|
print(rec5.count(2)) # MyMixIn's
|
|
print(rec5._replace(k=222))
|
|
print(rec5._replace(k=222).method())
|
|
print(rec5._replace(k=222)._my_custom_method()) # MyMixIn's
|
|
print(rec5._replace(k=222).count(2)) # MyMixIn's
|
|
|
|
# Note that behavior: the standard namedtuple methods cannot be
|
|
# overridden by a foreign mix-in -- even if the mix-in is declared
|
|
# as the leftmost base class (but, obviously, you can override them
|
|
# in the defined class or its subclasses):
|
|
|
|
print(rec4._asdict()) # (returns a dict, not "MyMixIn._asdict() called")
|
|
print(rec5._asdict()) # (returns a dict, not "MyMixIn._asdict() called")
|
|
|
|
class MyRecord6(MyRecord33):
|
|
_fields = 'j k l x y z'
|
|
def _asdict(self):
|
|
return "MyRecord6._asdict() called"
|
|
rec6 = MyRecord6(1, 2, 3, 1, 2, 3)
|
|
print(rec6._asdict()) # (this returns "MyRecord6._asdict() called")
|
|
|
|
# All that record classes are real subclasses of namedtuple.abc:
|
|
|
|
assert issubclass(MyRecord, namedtuple.abc)
|
|
assert issubclass(MyAbstractRecord, namedtuple.abc)
|
|
assert issubclass(AnotherAbstractRecord, namedtuple.abc)
|
|
assert issubclass(MyRecord2, namedtuple.abc)
|
|
assert issubclass(MyRecord3, namedtuple.abc)
|
|
assert issubclass(MyRecord33, namedtuple.abc)
|
|
assert issubclass(MyRecord345, namedtuple.abc)
|
|
assert issubclass(MyRecord4, namedtuple.abc)
|
|
assert issubclass(MyRecord5, namedtuple.abc)
|
|
assert issubclass(MyRecord6, namedtuple.abc)
|
|
|
|
# ...but abstract ones are not subclasses of tuple
|
|
# (and this is what you probably want):
|
|
|
|
assert not issubclass(MyAbstractRecord, tuple)
|
|
assert not issubclass(AnotherAbstractRecord, tuple)
|
|
|
|
assert issubclass(MyRecord, tuple)
|
|
assert issubclass(MyRecord2, tuple)
|
|
assert issubclass(MyRecord3, tuple)
|
|
assert issubclass(MyRecord33, tuple)
|
|
assert issubclass(MyRecord345, tuple)
|
|
assert issubclass(MyRecord4, tuple)
|
|
assert issubclass(MyRecord5, tuple)
|
|
assert issubclass(MyRecord6, tuple)
|
|
|
|
# Named tuple classes created with namedtuple() factory function
|
|
# (in the "traditional" way) are registered as "virtual" subclasses
|
|
# of namedtuple.abc:
|
|
|
|
MyTuple = namedtuple('MyTuple', 'a b c')
|
|
mt = MyTuple(1, 2, 3)
|
|
assert issubclass(MyTuple, namedtuple.abc)
|
|
assert isinstance(mt, namedtuple.abc)
|