# Copyright (C) 2012-2023 Ben Kurtovic <ben.kurtovic@gmail.com>
# Copyright (C) 2019-2020 Yuri Astrakhan <YuriAstrakhan@gmail.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import weakref
from .utils import _SliceNormalizerMixIn, inheritdoc
[docs]
class ListProxy(_SliceNormalizerMixIn, list):
"""Implement the ``list`` interface by getting elements from a parent.
This is created by a :class:`.SmartList` object when slicing. It does not
actually store the list at any time; instead, whenever the list is needed,
it builds it dynamically using the :meth:`_render` method.
"""
__slots__ = ("__weakref__", "_parent", "_sliceinfo")
def __init__(self, parent, sliceinfo):
super().__init__()
self._parent = parent
self._sliceinfo = sliceinfo
def __reduce_ex__(self, protocol: int) -> tuple:
return (ListProxy, (self._parent, self._sliceinfo), ())
def __setstate__(self, state: tuple) -> None:
# Reregister with the parent
child_ref = weakref.ref(self, self._parent._delete_child)
self._parent._children[id(child_ref)] = (child_ref, self._sliceinfo)
def __repr__(self):
return repr(self._render())
def __lt__(self, other):
if isinstance(other, ListProxy):
return self._render() < list(other)
return self._render() < other
def __le__(self, other):
if isinstance(other, ListProxy):
return self._render() <= list(other)
return self._render() <= other
def __eq__(self, other):
if isinstance(other, ListProxy):
return self._render() == list(other)
return self._render() == other
def __ne__(self, other):
if isinstance(other, ListProxy):
return self._render() != list(other)
return self._render() != other
def __gt__(self, other):
if isinstance(other, ListProxy):
return self._render() > list(other)
return self._render() > other
def __ge__(self, other):
if isinstance(other, ListProxy):
return self._render() >= list(other)
return self._render() >= other
def __bool__(self):
return bool(self._render())
def __len__(self):
return max((self._stop - self._start) // self._step, 0)
def __getitem__(self, key):
if isinstance(key, slice):
key = self._normalize_slice(key, clamp=True)
keystart = min(self._start + key.start, self._stop)
keystop = min(self._start + key.stop, self._stop)
adjusted = slice(keystart, keystop, key.step)
return self._parent[adjusted]
return self._render()[key]
def __setitem__(self, key, item):
if isinstance(key, slice):
key = self._normalize_slice(key, clamp=True)
keystart = min(self._start + key.start, self._stop)
keystop = min(self._start + key.stop, self._stop)
adjusted = slice(keystart, keystop, key.step)
self._parent[adjusted] = item
else:
length = len(self)
if key < 0:
key = length + key
if key < 0 or key >= length:
raise IndexError("list assignment index out of range")
self._parent[self._start + key] = item
def __delitem__(self, key):
if isinstance(key, slice):
key = self._normalize_slice(key, clamp=True)
keystart = min(self._start + key.start, self._stop)
keystop = min(self._start + key.stop, self._stop)
adjusted = slice(keystart, keystop, key.step)
del self._parent[adjusted]
else:
length = len(self)
if key < 0:
key = length + key
if key < 0 or key >= length:
raise IndexError("list assignment index out of range")
del self._parent[self._start + key]
def __iter__(self):
i = self._start
while i < self._stop:
yield self._parent[i]
i += self._step
def __reversed__(self):
i = self._stop - 1
while i >= self._start:
yield self._parent[i]
i -= self._step
def __contains__(self, item):
return item in self._render()
def __add__(self, other):
return type(self._parent)(list(self) + other)
def __radd__(self, other):
return type(self._parent)(other + list(self))
def __iadd__(self, other):
self.extend(other)
return self
def __mul__(self, other):
return type(self._parent)(list(self) * other)
def __rmul__(self, other):
return type(self._parent)(other * list(self))
def __imul__(self, other):
self.extend(list(self) * (other - 1))
return self
@property
def _start(self):
"""The starting index of this list, inclusive."""
return self._sliceinfo[0]
@property
def _stop(self):
"""The ending index of this list, exclusive."""
if self._sliceinfo[1] is None:
return len(self._parent)
return self._sliceinfo[1]
@property
def _step(self):
"""The number to increase the index by between items."""
return self._sliceinfo[2]
def _render(self):
"""Return the actual list from the stored start/stop/step."""
return list(self._parent)[self._start : self._stop : self._step]
[docs]
@inheritdoc
def append(self, item):
self._parent.insert(self._stop, item)
[docs]
@inheritdoc
def count(self, item):
return self._render().count(item)
[docs]
@inheritdoc
def index(self, item, start=None, stop=None):
if start is not None:
if stop is not None:
return self._render().index(item, start, stop)
return self._render().index(item, start)
return self._render().index(item)
[docs]
@inheritdoc
def extend(self, item):
self._parent[self._stop : self._stop] = item
[docs]
@inheritdoc
def insert(self, index, item):
if index < 0:
index = len(self) + index
self._parent.insert(self._start + index, item)
[docs]
@inheritdoc
def pop(self, index=None):
length = len(self)
if index is None:
index = length - 1
elif index < 0:
index = length + index
if index < 0 or index >= length:
raise IndexError("pop index out of range")
return self._parent.pop(self._start + index)
[docs]
@inheritdoc
def remove(self, item):
index = self.index(item)
del self._parent[self._start + index]
[docs]
@inheritdoc
def reverse(self):
item = self._render()
item.reverse()
self._parent[self._start : self._stop : self._step] = item
[docs]
@inheritdoc
def sort(self, key=None, reverse=None):
item = self._render()
kwargs = {}
if key is not None:
kwargs["key"] = key
if reverse is not None:
kwargs["reverse"] = reverse
item.sort(**kwargs)
self._parent[self._start : self._stop : self._step] = item