Use typing.Self where possible. #287

src/reader/_parser/requests/_lazy.py

@@ -12,6 +12,7 @@
 from . import TimeoutType
 
 if TYPE_CHECKING:  # pragma: no cover
+    from typing_extensions import Self
     from . import Headers
     from . import RequestHook
     from . import ResponseHook
@@ -136,8 +137,7 @@ def caching_get(
 
         return response, etag, last_modified
 
-    def __enter__(self: _T) -> _T:
-        # TODO: use typing.Self instead of _T
+    def __enter__(self) -> Self:
         return self
 
     def __exit__(self, *args: Any) -> None:

src/reader/_sql_utils.py

@@ -36,11 +36,14 @@
 from typing import TypeVar
 from typing import Union
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing_extensions import Self
+
+
 _T = TypeVar('_T')
 _U = TypeVar('_U')
 
 
-_Q = TypeVar('_Q', bound='BaseQuery')
 _QArg = Union[str, tuple[str, ...]]
 
 
@@ -108,7 +111,7 @@ def __init__(
         if separators is not None:
             self.separators = separators
 
-    def add(self: _Q, keyword: str, *args: _QArg) -> _Q:
+    def add(self, keyword: str, *args: _QArg) -> Self:
         keyword, fake_keyword = self._resolve_fakes(keyword)
         keyword, flag = self._resolve_flags(keyword)
         target = self.data[keyword]
@@ -143,7 +146,7 @@ def _resolve_flags(self, keyword: str) -> tuple[str, str]:
             return prefix, flag
         return keyword, ''
 
-    def __getattr__(self: _Q, name: str) -> Callable[..., _Q]:
+    def __getattr__(self, name: str) -> Callable[..., Self]:
         # conveniently, avoids shadowing dunder methods (e.g. __deepcopy__)
         if not name.isupper():
             return getattr(super(), name)  # type: ignore
@@ -206,8 +209,8 @@ def __init__(self, *args: Any, **kwargs: Any):
         self.scrolling_window_order_by()
 
     def scrolling_window_order_by(
-        self: _SWM, *things: str, desc: bool = False, keyword: str = 'WHERE'
-    ) -> _SWM:
+        self, *things: str, desc: bool = False, keyword: str = 'WHERE'
+    ) -> Self:
         self.__things = [_clean_up(t) for t in things]
         self.__desc = desc
         self.__keyword = keyword
@@ -225,7 +228,7 @@ def add_last(self, last: tuple[_T, ...] | None) -> list[tuple[str, _T]]:
 
     __make_label = 'last_{}'.format
 
-    def __add_last(self: _SWM) -> None:
+    def __add_last(self) -> None:
         op = '<' if self.__desc else '>'
         labels = (':' + self.__make_label(i) for i in range(len(self.__things)))
         comparison = BaseQuery({'(': self.__things, f') {op} (': labels, ')': ['']})

src/reader/_types.py

@@ -18,6 +18,7 @@
 from typing import NamedTuple
 from typing import overload
 from typing import Protocol
+from typing import TYPE_CHECKING
 from typing import TypeVar
 from typing import Union
 
@@ -49,6 +50,10 @@
 from .types import TagFilterInput
 from .types import TristateFilterInput
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing_extensions import Self
+
+
 log = logging.getLogger("reader")
 
 # Private API
@@ -434,9 +439,6 @@ def tristate_filter_argument(value: TristateFilterInput, name: str) -> TristateF
     raise ValueError(f"{name} must be none, bool, or one of {args}")
 
 
-_EFO = TypeVar('_EFO', bound='EntryFilter')
-
-
 class EntryFilter(NamedTuple):
 
     """Options for filtering the results of the "get entry" storage methods."""
@@ -450,14 +452,14 @@ class EntryFilter(NamedTuple):
 
     @classmethod
     def from_args(
-        cls: type[_EFO],
+        cls,
         feed: FeedInput | None = None,
         entry: EntryInput | None = None,
         read: bool | None = None,
         important: TristateFilterInput = None,
         has_enclosures: bool | None = None,
         feed_tags: TagFilterInput = None,
-    ) -> _EFO:
+    ) -> Self:
         feed_url = _feed_argument(feed) if feed is not None else None
 
         # TODO: should we allow specifying both feed and entry?
@@ -480,9 +482,6 @@ def from_args(
         )
 
 
-_FFO = TypeVar('_FFO', bound='FeedFilter')
-
-
 class FeedFilter(NamedTuple):
 
     """Options for filtering the results of the "get feed" storage methods."""
@@ -495,13 +494,13 @@ class FeedFilter(NamedTuple):
 
     @classmethod
     def from_args(
-        cls: type[_FFO],
+        cls,
         feed: FeedInput | None = None,
         tags: TagFilterInput = None,
         broken: bool | None = None,
         updates_enabled: bool | None = None,
         new: bool | None = None,
-    ) -> _FFO:
+    ) -> Self:
         feed_url = _feed_argument(feed) if feed is not None else None
         tag_filter = tag_filter_argument(tags)
 
@@ -522,7 +521,7 @@ class NameScheme(_namedtuple_compat):
     separator: str
 
     @classmethod
-    def from_value(cls, value: Mapping[str, str]) -> NameScheme:
+    def from_value(cls, value: Mapping[str, str]) -> Self:
         # Use is validation.
         self = cls(**value)
         self.make_reader_name('key')

src/reader/core.py

@@ -78,6 +78,7 @@
 from .types import UpdateResult
 
 if TYPE_CHECKING:  # pragma: no cover
+    from typing_extensions import Self
     from ._parser import Parser
 
 
@@ -86,8 +87,6 @@
 
 _T = TypeVar('_T')
 _U = TypeVar('_U')
-# mypy doesn't seem to support Self yet.
-_TReader = TypeVar('_TReader', bound='Reader')
 
 AfterEntryUpdateHook = Callable[['Reader', EntryData, EntryUpdateStatus], None]
 FeedUpdateHook = Callable[['Reader', str], None]
@@ -384,7 +383,7 @@ def __init__(
                 stacklevel=2,
             )
 
-    def __enter__(self: _TReader) -> _TReader:
+    def __enter__(self) -> Self:
         self._storage.__enter__()
         return self
 

src/reader/types.py

@@ -19,7 +19,7 @@
 from typing import overload
 from typing import Protocol
 from typing import runtime_checkable
-from typing import TypeVar
+from typing import TYPE_CHECKING
 from typing import Union
 
 from reader.exceptions import UpdateError
@@ -29,8 +29,8 @@
 from reader._utils import MISSING as MISSING  # noqa: F401
 from reader._utils import MissingType as MissingType  # noqa: F401
 
-
-_T = TypeVar('_T')
+if TYPE_CHECKING:  # pragma: no cover
+    from typing_extensions import Self
 
 
 class _namedtuple_compat:
@@ -40,7 +40,7 @@ class _namedtuple_compat:
     # TODO: can we get rid of _namedtuple_compat?
 
     @classmethod
-    def _make(cls: type[_T], iterable: Iterable[Any]) -> _T:
+    def _make(cls, iterable: Iterable[Any]) -> Self:
         iterable = tuple(iterable)
         attrs_len = len(dataclasses.fields(cls))  # type: ignore[arg-type]
         if len(iterable) != attrs_len:
@@ -49,7 +49,7 @@ def _make(cls: type[_T], iterable: Iterable[Any]) -> _T:
             )
         return cls(*iterable)
 
-    def _replace(self: _T, **kargs: Any) -> _T:
+    def _replace(self, **kargs: Any) -> Self:
         return dataclasses.replace(self, **kargs)  # type: ignore[type-var,misc]
 
     def _asdict(self) -> dict[str, Any]:
@@ -162,9 +162,6 @@ def resource_id(self) -> tuple[str]:
         return (self.url,)
 
 
-_EI = TypeVar('_EI', bound='ExceptionInfo')
-
-
 @dataclass(frozen=True)
 class ExceptionInfo(_namedtuple_compat):
 
@@ -187,7 +184,7 @@ class ExceptionInfo(_namedtuple_compat):
     traceback_str: str
 
     @classmethod
-    def from_exception(cls: type[_EI], exc: BaseException) -> _EI:
+    def from_exception(cls, exc: BaseException) -> Self:
         return cls(
             f'{type(exc).__module__}.{type(exc).__qualname__}',
             str(exc),
@@ -430,9 +427,6 @@ class Enclosure(_namedtuple_compat):
     length: int | None = None
 
 
-_HS = TypeVar('_HS', bound='HighlightedString')
-
-
 @dataclass(frozen=True)
 class HighlightedString:
 
@@ -486,7 +480,7 @@ def __str__(self) -> str:
         return self.value
 
     @classmethod
-    def extract(cls: type[_HS], text: str, before: str, after: str) -> _HS:
+    def extract(cls, text: str, before: str, after: str) -> Self:
         """Extract highlights with before/after markers from text.
 
         >>> HighlightedString.extract( '>one< two', '>', '<')