/usr/lib/python2.7/dist-packages/sqlalchemy/orm/identity.py is in python-sqlalchemy 0.8.4-1build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 | # orm/identity.py
# Copyright (C) 2005-2013 the SQLAlchemy authors and contributors <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: http://www.opensource.org/licenses/mit-license.php
import weakref
from . import attributes
class IdentityMap(dict):
def __init__(self):
self._modified = set()
self._wr = weakref.ref(self)
def replace(self, state):
raise NotImplementedError()
def add(self, state):
raise NotImplementedError()
def update(self, dict):
raise NotImplementedError("IdentityMap uses add() to insert data")
def clear(self):
raise NotImplementedError("IdentityMap uses remove() to remove data")
def _manage_incoming_state(self, state):
state._instance_dict = self._wr
if state.modified:
self._modified.add(state)
def _manage_removed_state(self, state):
del state._instance_dict
self._modified.discard(state)
def _dirty_states(self):
return self._modified
def check_modified(self):
"""return True if any InstanceStates present have been marked
as 'modified'.
"""
return bool(self._modified)
def has_key(self, key):
return key in self
def popitem(self):
raise NotImplementedError("IdentityMap uses remove() to remove data")
def pop(self, key, *args):
raise NotImplementedError("IdentityMap uses remove() to remove data")
def setdefault(self, key, default=None):
raise NotImplementedError("IdentityMap uses add() to insert data")
def copy(self):
raise NotImplementedError()
def __setitem__(self, key, value):
raise NotImplementedError("IdentityMap uses add() to insert data")
def __delitem__(self, key):
raise NotImplementedError("IdentityMap uses remove() to remove data")
class WeakInstanceDict(IdentityMap):
def __init__(self):
IdentityMap.__init__(self)
def __getitem__(self, key):
state = dict.__getitem__(self, key)
o = state.obj()
if o is None:
raise KeyError, key
return o
def __contains__(self, key):
try:
if dict.__contains__(self, key):
state = dict.__getitem__(self, key)
o = state.obj()
else:
return False
except KeyError:
return False
else:
return o is not None
def contains_state(self, state):
return dict.get(self, state.key) is state
def replace(self, state):
if dict.__contains__(self, state.key):
existing = dict.__getitem__(self, state.key)
if existing is not state:
self._manage_removed_state(existing)
else:
return
dict.__setitem__(self, state.key, state)
self._manage_incoming_state(state)
def add(self, state):
key = state.key
# inline of self.__contains__
if dict.__contains__(self, key):
try:
existing_state = dict.__getitem__(self, key)
if existing_state is not state:
o = existing_state.obj()
if o is not None:
raise AssertionError(
"A conflicting state is already "
"present in the identity map for key %r"
% (key, ))
else:
return
except KeyError:
pass
dict.__setitem__(self, key, state)
self._manage_incoming_state(state)
def get(self, key, default=None):
state = dict.get(self, key, default)
if state is default:
return default
o = state.obj()
if o is None:
return default
return o
def _items(self):
values = self.all_states()
result = []
for state in values:
value = state.obj()
if value is not None:
result.append((state.key, value))
return result
def _values(self):
values = self.all_states()
result = []
for state in values:
value = state.obj()
if value is not None:
result.append(value)
return result
# Py3K
#def items(self):
# return iter(self._items())
#
#def values(self):
# return iter(self._values())
# Py2K
items = _items
def iteritems(self):
return iter(self.items())
values = _values
def itervalues(self):
return iter(self.values())
# end Py2K
def all_states(self):
# Py3K
# return list(dict.values(self))
# Py2K
return dict.values(self)
# end Py2K
def discard(self, state):
st = dict.get(self, state.key, None)
if st is state:
dict.pop(self, state.key, None)
self._manage_removed_state(state)
def prune(self):
return 0
class StrongInstanceDict(IdentityMap):
def all_states(self):
return [attributes.instance_state(o) for o in self.itervalues()]
def contains_state(self, state):
return (
state.key in self and
attributes.instance_state(self[state.key]) is state)
def replace(self, state):
if dict.__contains__(self, state.key):
existing = dict.__getitem__(self, state.key)
existing = attributes.instance_state(existing)
if existing is not state:
self._manage_removed_state(existing)
else:
return
dict.__setitem__(self, state.key, state.obj())
self._manage_incoming_state(state)
def add(self, state):
if state.key in self:
if attributes.instance_state(dict.__getitem__(self,
state.key)) is not state:
raise AssertionError('A conflicting state is already '
'present in the identity map for key %r'
% (state.key, ))
else:
dict.__setitem__(self, state.key, state.obj())
self._manage_incoming_state(state)
def discard(self, state):
obj = dict.get(self, state.key, None)
if obj is not None:
st = attributes.instance_state(obj)
if st is state:
dict.pop(self, state.key, None)
self._manage_removed_state(state)
def prune(self):
"""prune unreferenced, non-dirty states."""
ref_count = len(self)
dirty = [s.obj() for s in self.all_states() if s.modified]
# work around http://bugs.python.org/issue6149
keepers = weakref.WeakValueDictionary()
keepers.update(self)
dict.clear(self)
dict.update(self, keepers)
self.modified = bool(dirty)
return ref_count - len(self)
|