Mini Shell
# util.py
import contextlib
from functools import lru_cache, wraps
import inspect
import itertools
import types
from typing import Callable, Union, Iterable, TypeVar, cast
import warnings
_bslash = chr(92)
C = TypeVar("C", bound=Callable)
class __config_flags:
"""Internal class for defining compatibility and debugging flags"""
_all_names: list[str] = []
_fixed_names: list[str] = []
_type_desc = "configuration"
@classmethod
def _set(cls, dname, value):
if dname in cls._fixed_names:
warnings.warn(
f"{cls.__name__}.{dname} {cls._type_desc} is {str(getattr(cls, dname)).upper()}"
f" and cannot be overridden",
stacklevel=3,
)
return
if dname in cls._all_names:
setattr(cls, dname, value)
else:
raise ValueError(f"no such {cls._type_desc} {dname!r}")
enable = classmethod(lambda cls, name: cls._set(name, True))
disable = classmethod(lambda cls, name: cls._set(name, False))
@lru_cache(maxsize=128)
def col(loc: int, strg: str) -> int:
"""
Returns current column within a string, counting newlines as line separators.
The first column is number 1.
Note: the default parsing behavior is to expand tabs in the input string
before starting the parsing process. See
:class:`ParserElement.parse_string` for more
information on parsing strings containing ``<TAB>`` s, and suggested
methods to maintain a consistent view of the parsed string, the parse
location, and line and column positions within the parsed string.
"""
s = strg
return 1 if 0 < loc < len(s) and s[loc - 1] == "\n" else loc - s.rfind("\n", 0, loc)
@lru_cache(maxsize=128)
def lineno(loc: int, strg: str) -> int:
"""Returns current line number within a string, counting newlines as line separators.
The first line is number 1.
Note - the default parsing behavior is to expand tabs in the input string
before starting the parsing process. See :class:`ParserElement.parse_string`
for more information on parsing strings containing ``<TAB>`` s, and
suggested methods to maintain a consistent view of the parsed string, the
parse location, and line and column positions within the parsed string.
"""
return strg.count("\n", 0, loc) + 1
@lru_cache(maxsize=128)
def line(loc: int, strg: str) -> str:
"""
Returns the line of text containing loc within a string, counting newlines as line separators.
"""
last_cr = strg.rfind("\n", 0, loc)
next_cr = strg.find("\n", loc)
return strg[last_cr + 1 : next_cr] if next_cr >= 0 else strg[last_cr + 1 :]
class _UnboundedCache:
def __init__(self):
cache = {}
cache_get = cache.get
self.not_in_cache = not_in_cache = object()
def get(_, key):
return cache_get(key, not_in_cache)
def set_(_, key, value):
cache[key] = value
def clear(_):
cache.clear()
self.size = None
self.get = types.MethodType(get, self)
self.set = types.MethodType(set_, self)
self.clear = types.MethodType(clear, self)
class _FifoCache:
def __init__(self, size):
cache = {}
self.size = size
self.not_in_cache = not_in_cache = object()
cache_get = cache.get
cache_pop = cache.pop
def get(_, key):
return cache_get(key, not_in_cache)
def set_(_, key, value):
cache[key] = value
while len(cache) > size:
# pop oldest element in cache by getting the first key
cache_pop(next(iter(cache)))
def clear(_):
cache.clear()
self.get = types.MethodType(get, self)
self.set = types.MethodType(set_, self)
self.clear = types.MethodType(clear, self)
class LRUMemo:
"""
A memoizing mapping that retains `capacity` deleted items
The memo tracks retained items by their access order; once `capacity` items
are retained, the least recently used item is discarded.
"""
def __init__(self, capacity):
self._capacity = capacity
self._active = {}
self._memory = {}
def __getitem__(self, key):
try:
return self._active[key]
except KeyError:
self._memory[key] = self._memory.pop(key)
return self._memory[key]
def __setitem__(self, key, value):
self._memory.pop(key, None)
self._active[key] = value
def __delitem__(self, key):
try:
value = self._active.pop(key)
except KeyError:
pass
else:
oldest_keys = list(self._memory)[: -(self._capacity + 1)]
for key_to_delete in oldest_keys:
self._memory.pop(key_to_delete)
self._memory[key] = value
def clear(self):
self._active.clear()
self._memory.clear()
class UnboundedMemo(dict):
"""
A memoizing mapping that retains all deleted items
"""
def __delitem__(self, key):
pass
def _escape_regex_range_chars(s: str) -> str:
# escape these chars: ^-[]
for c in r"\^-[]":
s = s.replace(c, _bslash + c)
s = s.replace("\n", r"\n")
s = s.replace("\t", r"\t")
return str(s)
class _GroupConsecutive:
"""
Used as a callable `key` for itertools.groupby to group
characters that are consecutive:
itertools.groupby("abcdejkmpqrs", key=IsConsecutive())
yields:
(0, iter(['a', 'b', 'c', 'd', 'e']))
(1, iter(['j', 'k']))
(2, iter(['m']))
(3, iter(['p', 'q', 'r', 's']))
"""
def __init__(self):
self.prev = 0
self.counter = itertools.count()
self.value = -1
def __call__(self, char: str) -> int:
c_int = ord(char)
self.prev, prev = c_int, self.prev
if c_int - prev > 1:
self.value = next(self.counter)
return self.value
def _collapse_string_to_ranges(
s: Union[str, Iterable[str]], re_escape: bool = True
) -> str:
r"""
Take a string or list of single-character strings, and return
a string of the consecutive characters in that string collapsed
into groups, as might be used in a regular expression '[a-z]'
character set:
'a' -> 'a' -> '[a]'
'bc' -> 'bc' -> '[bc]'
'defgh' -> 'd-h' -> '[d-h]'
'fdgeh' -> 'd-h' -> '[d-h]'
'jklnpqrtu' -> 'j-lnp-rtu' -> '[j-lnp-rtu]'
Duplicates get collapsed out:
'aaa' -> 'a' -> '[a]'
'bcbccb' -> 'bc' -> '[bc]'
'defghhgf' -> 'd-h' -> '[d-h]'
'jklnpqrjjjtu' -> 'j-lnp-rtu' -> '[j-lnp-rtu]'
Spaces are preserved:
'ab c' -> ' a-c' -> '[ a-c]'
Characters that are significant when defining regex ranges
get escaped:
'acde[]-' -> r'\-\[\]ac-e' -> r'[\-\[\]ac-e]'
"""
# Developer notes:
# - Do not optimize this code assuming that the given input string
# or internal lists will be short (such as in loading generators into
# lists to make it easier to find the last element); this method is also
# used to generate regex ranges for character sets in the pyparsing.unicode
# classes, and these can be _very_ long lists of strings
def escape_re_range_char(c: str) -> str:
return "\\" + c if c in r"\^-][" else c
def no_escape_re_range_char(c: str) -> str:
return c
if not re_escape:
escape_re_range_char = no_escape_re_range_char
ret = []
# reduce input string to remove duplicates, and put in sorted order
s_chars: list[str] = sorted(set(s))
if len(s_chars) > 2:
# find groups of characters that are consecutive (can be collapsed
# down to "<first>-<last>")
for _, chars in itertools.groupby(s_chars, key=_GroupConsecutive()):
# _ is unimportant, is just used to identify groups
# chars is an iterator of one or more consecutive characters
# that comprise the current group
first = last = next(chars)
with contextlib.suppress(ValueError):
*_, last = chars
if first == last:
# there was only a single char in this group
ret.append(escape_re_range_char(first))
elif last == chr(ord(first) + 1):
# there were only 2 characters in this group
# 'a','b' -> 'ab'
ret.append(f"{escape_re_range_char(first)}{escape_re_range_char(last)}")
else:
# there were > 2 characters in this group, make into a range
# 'c','d','e' -> 'c-e'
ret.append(
f"{escape_re_range_char(first)}-{escape_re_range_char(last)}"
)
else:
# only 1 or 2 chars were given to form into groups
# 'a' -> ['a']
# 'bc' -> ['b', 'c']
# 'dg' -> ['d', 'g']
# no need to list them with "-", just return as a list
# (after escaping)
ret = [escape_re_range_char(c) for c in s_chars]
return "".join(ret)
def _flatten(ll: Iterable) -> list:
ret = []
to_visit = [*ll]
while to_visit:
i = to_visit.pop(0)
if isinstance(i, Iterable) and not isinstance(i, str):
to_visit[:0] = i
else:
ret.append(i)
return ret
def make_compressed_re(
word_list: Iterable[str], max_level: int = 2, _level: int = 1
) -> str:
"""
Create a regular expression string from a list of words, collapsing by common
prefixes and optional suffixes.
Calls itself recursively to build nested sublists for each group of suffixes
that have a shared prefix.
"""
def get_suffixes_from_common_prefixes(namelist: list[str]):
if len(namelist) > 1:
for prefix, suffixes in itertools.groupby(namelist, key=lambda s: s[:1]):
yield prefix, sorted([s[1:] for s in suffixes], key=len, reverse=True)
else:
yield namelist[0][0], [namelist[0][1:]]
if max_level == 0:
return "|".join(sorted(word_list, key=len, reverse=True))
ret = []
sep = ""
for initial, suffixes in get_suffixes_from_common_prefixes(sorted(word_list)):
ret.append(sep)
sep = "|"
trailing = ""
if "" in suffixes:
trailing = "?"
suffixes.remove("")
if len(suffixes) > 1:
if all(len(s) == 1 for s in suffixes):
ret.append(f"{initial}[{''.join(suffixes)}]{trailing}")
else:
if _level < max_level:
suffix_re = make_compressed_re(
sorted(suffixes), max_level, _level + 1
)
ret.append(f"{initial}({suffix_re}){trailing}")
else:
suffixes.sort(key=len, reverse=True)
ret.append(f"{initial}({'|'.join(suffixes)}){trailing}")
else:
if suffixes:
suffix = suffixes[0]
if len(suffix) > 1 and trailing:
ret.append(f"{initial}({suffix}){trailing}")
else:
ret.append(f"{initial}{suffix}{trailing}")
else:
ret.append(initial)
return "".join(ret)
def replaced_by_pep8(compat_name: str, fn: C) -> C:
# In a future version, uncomment the code in the internal _inner() functions
# to begin emitting DeprecationWarnings.
# Unwrap staticmethod/classmethod
fn = getattr(fn, "__func__", fn)
# (Presence of 'self' arg in signature is used by explain_exception() methods, so we take
# some extra steps to add it if present in decorated function.)
if ["self"] == list(inspect.signature(fn).parameters)[:1]:
@wraps(fn)
def _inner(self, *args, **kwargs):
# warnings.warn(
# f"Deprecated - use {fn.__name__}", DeprecationWarning, stacklevel=2
# )
return fn(self, *args, **kwargs)
else:
@wraps(fn)
def _inner(*args, **kwargs):
# warnings.warn(
# f"Deprecated - use {fn.__name__}", DeprecationWarning, stacklevel=2
# )
return fn(*args, **kwargs)
_inner.__doc__ = f"""Deprecated - use :class:`{fn.__name__}`"""
_inner.__name__ = compat_name
_inner.__annotations__ = fn.__annotations__
if isinstance(fn, types.FunctionType):
_inner.__kwdefaults__ = fn.__kwdefaults__ # type: ignore [attr-defined]
elif isinstance(fn, type) and hasattr(fn, "__init__"):
_inner.__kwdefaults__ = fn.__init__.__kwdefaults__ # type: ignore [misc,attr-defined]
else:
_inner.__kwdefaults__ = None # type: ignore [attr-defined]
_inner.__qualname__ = fn.__qualname__
return cast(C, _inner)
Zerion Mini Shell 1.0