Files
babi/babi/list_spy.py
2020-03-13 20:49:59 -07:00

86 lines
2.4 KiB
Python

import functools
import sys
from typing import Callable
from typing import Iterator
from typing import List
from babi._types import Protocol
class SequenceNoSlice(Protocol):
def __len__(self) -> int: ...
def __getitem__(self, idx: int) -> str: ...
def __iter__(self) -> Iterator[str]:
for i in range(len(self)):
yield self[i]
class MutableSequenceNoSlice(SequenceNoSlice, Protocol):
def __setitem__(self, idx: int, val: str) -> None: ...
def __delitem__(self, idx: int) -> None: ...
def insert(self, idx: int, val: str) -> None: ...
def append(self, val: str) -> None:
self.insert(len(self), val)
def pop(self, idx: int = -1) -> str:
victim = self[idx]
del self[idx]
return victim
def _del(lst: MutableSequenceNoSlice, *, idx: int) -> None:
del lst[idx]
def _set(lst: MutableSequenceNoSlice, *, idx: int, val: str) -> None:
lst[idx] = val
def _ins(lst: MutableSequenceNoSlice, *, idx: int, val: str) -> None:
lst.insert(idx, val)
class ListSpy(MutableSequenceNoSlice):
def __init__(self, lst: MutableSequenceNoSlice) -> None:
self._lst = lst
self._undo: List[Callable[[MutableSequenceNoSlice], None]] = []
self.min_line_touched = sys.maxsize
def __repr__(self) -> str:
return f'{type(self).__name__}({self._lst})'
def __len__(self) -> int:
return len(self._lst)
def __getitem__(self, idx: int) -> str:
return self._lst[idx]
def __setitem__(self, idx: int, val: str) -> None:
self._undo.append(functools.partial(_set, idx=idx, val=self._lst[idx]))
self.min_line_touched = min(idx, self.min_line_touched)
self._lst[idx] = val
def __delitem__(self, idx: int) -> None:
if idx < 0:
idx %= len(self)
self._undo.append(functools.partial(_ins, idx=idx, val=self._lst[idx]))
self.min_line_touched = min(idx, self.min_line_touched)
del self._lst[idx]
def insert(self, idx: int, val: str) -> None:
if idx < 0:
idx %= len(self)
self._undo.append(functools.partial(_del, idx=idx))
self.min_line_touched = min(idx, self.min_line_touched)
self._lst.insert(idx, val)
def undo(self, lst: MutableSequenceNoSlice) -> None:
for fn in reversed(self._undo):
fn(lst)
@property
def has_modifications(self) -> bool:
return bool(self._undo)