| | |
| |
|
| | import collections.abc |
| | from typing import Any, Callable |
| |
|
| | from dns._immutable_ctx import immutable |
| |
|
| |
|
| | @immutable |
| | class Dict(collections.abc.Mapping): |
| | def __init__( |
| | self, |
| | dictionary: Any, |
| | no_copy: bool = False, |
| | map_factory: Callable[[], collections.abc.MutableMapping] = dict, |
| | ): |
| | """Make an immutable dictionary from the specified dictionary. |
| | |
| | If *no_copy* is `True`, then *dictionary* will be wrapped instead |
| | of copied. Only set this if you are sure there will be no external |
| | references to the dictionary. |
| | """ |
| | if no_copy and isinstance(dictionary, collections.abc.MutableMapping): |
| | self._odict = dictionary |
| | else: |
| | self._odict = map_factory() |
| | self._odict.update(dictionary) |
| | self._hash = None |
| |
|
| | def __getitem__(self, key): |
| | return self._odict.__getitem__(key) |
| |
|
| | def __hash__(self): |
| | if self._hash is None: |
| | h = 0 |
| | for key in sorted(self._odict.keys()): |
| | h ^= hash(key) |
| | object.__setattr__(self, "_hash", h) |
| | |
| | return self._hash |
| |
|
| | def __len__(self): |
| | return len(self._odict) |
| |
|
| | def __iter__(self): |
| | return iter(self._odict) |
| |
|
| |
|
| | def constify(o: Any) -> Any: |
| | """ |
| | Convert mutable types to immutable types. |
| | """ |
| | if isinstance(o, bytearray): |
| | return bytes(o) |
| | if isinstance(o, tuple): |
| | try: |
| | hash(o) |
| | return o |
| | except Exception: |
| | return tuple(constify(elt) for elt in o) |
| | if isinstance(o, list): |
| | return tuple(constify(elt) for elt in o) |
| | if isinstance(o, dict): |
| | cdict = dict() |
| | for k, v in o.items(): |
| | cdict[k] = constify(v) |
| | return Dict(cdict, True) |
| | return o |
| |
|