Source code for rdflib.compat

"""
Utility functions and objects to ease Python 2/3 compatibility,
and different versions of support libraries.
"""

import codecs
import re
import warnings
from typing import Match


[docs]def cast_bytes(s, enc="utf-8"): if isinstance(s, str): return s.encode(enc) return s
[docs]def ascii(stream): return codecs.getreader("ascii")(stream)
[docs]def bopen(*args, **kwargs): return open(*args, mode="rb", **kwargs)
long_type = int
[docs]def sign(n): if n < 0: return -1 if n > 0: return 1 return 0
r_unicodeEscape = re.compile(r"(\\u[0-9A-Fa-f]{4}|\\U[0-9A-Fa-f]{8})") def _unicodeExpand(s): return r_unicodeEscape.sub(lambda m: chr(int(m.group(0)[2:], 16)), s)
[docs]def decodeStringEscape(s): warnings.warn( DeprecationWarning( "rdflib.compat.decodeStringEscape() is deprecated, " "it will be removed in rdflib 7.0.0. " "This function is not used anywhere in rdflib anymore " "and the utility that it does provide is not implemented correctly." ) ) r""" s is byte-string - replace \ escapes in string """ s = s.replace("\\t", "\t") s = s.replace("\\n", "\n") s = s.replace("\\r", "\r") s = s.replace("\\b", "\b") s = s.replace("\\f", "\f") s = s.replace('\\"', '"') s = s.replace("\\'", "'") s = s.replace("\\\\", "\\") return s
# return _unicodeExpand(s) # hmm - string escape doesn't do unicode escaping _string_escape_map = { "t": "\t", "b": "\b", "n": "\n", "r": "\r", "f": "\f", '"': '"', "'": "'", "\\": "\\", } def _turtle_escape_subber(match: Match[str]) -> str: smatch, umatch = match.groups() if smatch is not None: return _string_escape_map[smatch] else: return chr(int(umatch[1:], 16)) _turtle_escape_pattern = re.compile( r"""\\(?:([tbnrf"'\\])|(u[0-9A-Fa-f]{4}|U[0-9A-Fa-f]{8}))""", )
[docs]def decodeUnicodeEscape(escaped: str) -> str: if "\\" not in escaped: # Most of times, there are no backslashes in strings. return escaped return _turtle_escape_pattern.sub(_turtle_escape_subber, escaped)
# Migration to abc in Python 3.8 try: from collections.abc import Mapping, MutableMapping except: from collections import Mapping, MutableMapping