spaCy/spacy/tokens/_dict_proxies.py

77 lines
2.7 KiB
Python

from typing import Iterable, Tuple, Union, Optional, TYPE_CHECKING
import weakref
from collections import UserDict
import srsly
from .span_group import SpanGroup
from ..errors import Errors
if TYPE_CHECKING:
# This lets us add type hints for mypy etc. without causing circular imports
from .doc import Doc # noqa: F401
from .span import Span # noqa: F401
# Why inherit from UserDict instead of dict here?
# Well, the 'dict' class doesn't necessarily delegate everything nicely,
# for performance reasons. The UserDict is slower but better behaved.
# See https://treyhunner.com/2019/04/why-you-shouldnt-inherit-from-list-and-dict-in-python/0ww
class SpanGroups(UserDict):
"""A dict-like proxy held by the Doc, to control access to span groups."""
_EMPTY_BYTES = srsly.msgpack_dumps([])
def __init__(
self, doc: "Doc", items: Iterable[Tuple[str, SpanGroup]] = tuple()
) -> None:
self.doc_ref = weakref.ref(doc)
UserDict.__init__(self, items) # type: ignore[arg-type]
def __setitem__(self, key: str, value: Union[SpanGroup, Iterable["Span"]]) -> None:
if not isinstance(value, SpanGroup):
value = self._make_span_group(key, value)
assert value.doc is self.doc_ref()
UserDict.__setitem__(self, key, value)
def _make_span_group(self, name: str, spans: Iterable["Span"]) -> SpanGroup:
doc = self._ensure_doc()
return SpanGroup(doc, name=name, spans=spans)
def copy(self, doc: Optional["Doc"] = None) -> "SpanGroups":
if doc is None:
doc = self._ensure_doc()
return SpanGroups(doc).from_bytes(self.to_bytes())
def setdefault(self, key, default=None):
if not isinstance(default, SpanGroup):
if default is None:
spans = []
else:
spans = default
default = self._make_span_group(key, spans)
return super().setdefault(key, default=default)
def to_bytes(self) -> bytes:
# We don't need to serialize this as a dict, because the groups
# know their names.
if len(self) == 0:
return self._EMPTY_BYTES
msg = [value.to_bytes() for value in self.values()]
return srsly.msgpack_dumps(msg)
def from_bytes(self, bytes_data: bytes) -> "SpanGroups":
msg = [] if bytes_data == self._EMPTY_BYTES else srsly.msgpack_loads(bytes_data)
self.clear()
doc = self._ensure_doc()
for value_bytes in msg:
group = SpanGroup(doc).from_bytes(value_bytes)
self[group.name] = group
return self
def _ensure_doc(self) -> "Doc":
doc = self.doc_ref()
if doc is None:
raise ValueError(Errors.E866)
return doc