You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
43 lines
1.1 KiB
43 lines
1.1 KiB
5 years ago
|
"""Utilities for defining models
|
||
|
|
"""
|
||
|
|
# The following comment should be removed at some point in the future.
|
||
|
|
# mypy: disallow-untyped-defs=False
|
||
|
|
|
||
|
|
import operator
|
||
|
|
|
||
|
|
|
||
|
|
class KeyBasedCompareMixin(object):
|
||
|
|
"""Provides comparison capabilities that is based on a key
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, key, defining_class):
|
||
|
|
self._compare_key = key
|
||
|
|
self._defining_class = defining_class
|
||
|
|
|
||
|
|
def __hash__(self):
|
||
|
|
return hash(self._compare_key)
|
||
|
|
|
||
|
|
def __lt__(self, other):
|
||
|
|
return self._compare(other, operator.__lt__)
|
||
|
|
|
||
|
|
def __le__(self, other):
|
||
|
|
return self._compare(other, operator.__le__)
|
||
|
|
|
||
|
|
def __gt__(self, other):
|
||
|
|
return self._compare(other, operator.__gt__)
|
||
|
|
|
||
|
|
def __ge__(self, other):
|
||
|
|
return self._compare(other, operator.__ge__)
|
||
|
|
|
||
|
|
def __eq__(self, other):
|
||
|
|
return self._compare(other, operator.__eq__)
|
||
|
|
|
||
|
|
def __ne__(self, other):
|
||
|
|
return self._compare(other, operator.__ne__)
|
||
|
|
|
||
|
|
def _compare(self, other, method):
|
||
|
|
if not isinstance(other, self._defining_class):
|
||
|
|
return NotImplemented
|
||
|
|
|
||
|
|
return method(self._compare_key, other._compare_key)
|