# util.py import inspect import warnings import types import collections import itertools from functools import lru_cache, wraps from typing import Callable, List, Union, Iterable, TypeVar, cast _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 ```` 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 ```` 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): self.not_in_cache = not_in_cache = object() cache = {} keyring = [object()] * size cache_get = cache.get cache_pop = cache.pop keyiter = itertools.cycle(range(size)) def get(_, key): return cache_get(key, not_in_cache) def set_(_, key, value): cache[key] = value i = next(keyiter) cache_pop(keyring[i], None) keyring[i] = key def clear(_): cache.clear() keyring[:] = [object()] * size self.size = size 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 = collections.OrderedDict() def __getitem__(self, key): try: return self._active[key] except KeyError: self._memory.move_to_end(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: while len(self._memory) >= self._capacity: self._memory.popitem(last=False) 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) def _collapse_string_to_ranges( s: Union[str, Iterable[str]], re_escape: bool = True ) -> str: def is_consecutive(c): c_int = ord(c) is_consecutive.prev, prev = c_int, is_consecutive.prev if c_int - prev > 1: is_consecutive.value = next(is_consecutive.counter) return is_consecutive.value is_consecutive.prev = 0 # type: ignore [attr-defined] is_consecutive.counter = itertools.count() # type: ignore [attr-defined] is_consecutive.value = -1 # type: ignore [attr-defined] def escape_re_range_char(c): return "\\" + c if c in r"\^-][" else c def no_escape_re_range_char(c): return c if not re_escape: escape_re_range_char = no_escape_re_range_char ret = [] s = "".join(sorted(set(s))) if len(s) > 3: for _, chars in itertools.groupby(s, key=is_consecutive): first = last = next(chars) last = collections.deque( itertools.chain(iter([last]), chars), maxlen=1 ).pop() if first == last: ret.append(escape_re_range_char(first)) else: sep = "" if ord(last) == ord(first) + 1 else "-" ret.append( f"{escape_re_range_char(first)}{sep}{escape_re_range_char(last)}" ) else: ret = [escape_re_range_char(c) for c in s] return "".join(ret) def _flatten(ll: list) -> list: ret = [] for i in ll: if isinstance(i, list): ret.extend(_flatten(i)) else: ret.append(i) return 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)[0]: @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__ elif isinstance(fn, type) and hasattr(fn, "__init__"): _inner.__kwdefaults__ = fn.__init__.__kwdefaults__ else: _inner.__kwdefaults__ = None _inner.__qualname__ = fn.__qualname__ return cast(C, _inner)