Write union types as X | Y

pottery/base.py

@@ -16,6 +16,10 @@
 # --------------------------------------------------------------------------- #
 
 
+# TODO: When we drop support for Python 3.9, remove the following import.  We
+# only need it for X | Y union type annotations as of 2022-01-29.
+from __future__ import annotations
+
 import abc
 import collections
 import contextlib
@@ -31,8 +35,6 @@
 from typing import Generator
 from typing import Iterable
 from typing import List
-from typing import Mapping
-from typing import Optional
 from typing import Tuple
 from typing import cast
 
@@ -95,8 +97,8 @@ class _Common:
 
     def __init__(self,
                  *,
-                 redis: Optional[Redis] = None,
-                 key: Optional[str] = None,
+                 redis: Redis | None = None,
+                 key: str | None = None,
                  ) -> None:
         self.redis = cast(Redis, redis)
         self.key = cast(str, key)
@@ -118,7 +120,7 @@ def redis(self) -> Redis:
         return self.__redis
 
     @redis.setter
-    def redis(self, value: Optional[Redis]) -> None:
+    def redis(self, value: Redis | None) -> None:
         self.__redis = _default_redis if value is None else value
 
     @property
@@ -329,7 +331,7 @@ def key(self, value: str) -> None:
         self.__key = f'{self.KEY_PREFIX}:{value}'
 
     def _check_enough_masters_up(self,
-                                 raise_on_redis_errors: Optional[bool],
+                                 raise_on_redis_errors: bool | None,
                                  redis_errors: List[RedisError],
                                  ) -> None:
         if raise_on_redis_errors is None:

pottery/cache.py

@@ -30,7 +30,6 @@
 from typing import Hashable
 from typing import Iterable
 from typing import NamedTuple
-from typing import Optional
 from typing import TypeVar
 from typing import cast
 
@@ -60,7 +59,7 @@ class CacheInfo(NamedTuple):
     '''
     hits: int = 0
     misses: int = 0
-    maxsize: Optional[int] = None
+    maxsize: int | None = None
     currsize: int = 0
 
 
@@ -73,9 +72,9 @@ def _arg_hash(*args: Hashable, **kwargs: Hashable) -> int:
 
 
 def redis_cache(*,  # NoQA: C901
-                redis: Optional[Redis] = None,
-                key: Optional[str] = None,
-                timeout: Optional[int] = _DEFAULT_TIMEOUT,
+                redis: Redis | None = None,
+                key: str | None = None,
+                timeout: int | None = _DEFAULT_TIMEOUT,
                 ) -> Callable[[F], F]:
     '''Redis-backed caching decorator with an API like functools.lru_cache().
 
@@ -219,11 +218,11 @@ class CachedOrderedDict(collections.OrderedDict):
     @_set_expiration
     def __init__(self,
                  *,
-                 redis_client: Optional[Redis] = None,
-                 redis_key: Optional[str] = None,
+                 redis_client: Redis | None = None,
+                 redis_key: str | None = None,
                  dict_keys: Iterable[JSONTypes] = tuple(),
                  num_tries: int = _NUM_TRIES,
-                 timeout: Optional[int] = _DEFAULT_TIMEOUT,
+                 timeout: int | None = _DEFAULT_TIMEOUT,
                  ) -> None:
         self._num_tries = num_tries
         self._timeout = timeout

pottery/counter.py

@@ -29,7 +29,6 @@
 from typing import Callable
 from typing import Iterable
 from typing import List
-from typing import Optional
 from typing import Tuple
 from typing import Union
 from typing import cast
@@ -251,7 +250,7 @@ def __iand__(self, other: Counter[JSONTypes]) -> Counter[JSONTypes]:
         return self.__iset_op(other, method=int.__lt__)
 
     def most_common(self,
-                    n: Optional[int] = None,
+                    n: int | None = None,
                     ) -> List[Tuple[JSONTypes, int]]:
         counter = self.__to_counter()
         return counter.most_common(n=n)

pottery/deque.py

@@ -23,7 +23,6 @@
 import collections
 import warnings
 from typing import Iterable
-from typing import Optional
 from typing import Tuple
 from typing import cast
 
@@ -44,10 +43,10 @@ class RedisDeque(RedisList, collections.deque):  # type: ignore
 
     def __init__(self,
                  iterable: Iterable[JSONTypes] = tuple(),
-                 maxlen: Optional[int] = None,
+                 maxlen: int | None = None,
                  *,
-                 redis: Optional[Redis] = None,
-                 key: Optional[str] = None,
+                 redis: Redis | None = None,
+                 key: str | None = None,
                  ) -> None:
         'Initialize the RedisDeque.  O(n)'
         if maxlen is not None and not isinstance(maxlen, int):
@@ -73,7 +72,7 @@ def _populate(self,
         super()._populate(pipeline, iterable)
 
     @property
-    def maxlen(self) -> Optional[int]:
+    def maxlen(self) -> int | None:
         return self._maxlen
 
     @maxlen.setter

pottery/dict.py

@@ -16,6 +16,10 @@
 # --------------------------------------------------------------------------- #
 
 
+# TODO: When we drop support for Python 3.9, remove the following import.  We
+# only need it for X | Y union type annotations as of 2022-01-29.
+from __future__ import annotations
+
 import collections.abc
 import itertools
 import warnings
@@ -24,7 +28,6 @@
 from typing import Generator
 from typing import Iterable
 from typing import Mapping
-from typing import Optional
 from typing import Tuple
 from typing import Union
 from typing import cast
@@ -51,8 +54,8 @@ class RedisDict(Base, Iterable_, collections.abc.MutableMapping):
     def __init__(self,
                  arg: InitArg = tuple(),
                  *,
-                 redis: Optional[Redis] = None,
-                 key: Optional[str] = None,
+                 redis: Redis | None = None,
+                 key: str | None = None,
                  **kwargs: JSONTypes,
                  ) -> None:
         'Initialize the RedisDict.  O(n)'

pottery/exceptions.py

@@ -16,10 +16,13 @@
 # --------------------------------------------------------------------------- #
 
 
+# TODO: When we drop support for Python 3.9, remove the following import.  We
+# only need it for X | Y union type annotations as of 2022-01-29.
+from __future__ import annotations
+
 from dataclasses import dataclass
 from queue import Empty
 from typing import Iterable
-from typing import Optional
 
 from redis import Redis
 from redis import RedisError
@@ -30,7 +33,7 @@ class PotteryError(Exception):
     'Base exception class for Pottery containers.'
 
     redis: Redis
-    key: Optional[str] = None
+    key: str | None = None
 
 class KeyExistsError(PotteryError):
     'Initializing a container on a Redis key that already exists.'

pottery/executor.py

@@ -16,9 +16,12 @@
 # --------------------------------------------------------------------------- #
 
 
+# TODO: When we drop support for Python 3.9, remove the following import.  We
+# only need it for X | Y union type annotations as of 2022-01-29.
+from __future__ import annotations
+
 import concurrent.futures
 from types import TracebackType
-from typing import Optional
 from typing import Type
 from typing import overload
 
@@ -69,9 +72,9 @@ def __exit__(self,
         raise NotImplementedError
 
     def __exit__(self,
-                 exc_type: Optional[Type[BaseException]],
-                 exc_value: Optional[BaseException],
-                 exc_traceback: Optional[TracebackType],
+                 exc_type: Type[BaseException] | None,
+                 exc_value: BaseException | None,
+                 exc_traceback: TracebackType | None,
                  ) -> Literal[False]:
         self.shutdown(wait=False)
         return False

pottery/hyper.py

@@ -27,7 +27,6 @@
 from typing import Generator
 from typing import Iterable
 from typing import List
-from typing import Optional
 from typing import cast
 
 from redis import Redis
@@ -107,8 +106,8 @@ class HyperLogLog(Base):
     def __init__(self,
                  iterable: Iterable[RedisValues] = frozenset(),
                  *,
-                 redis: Optional[Redis] = None,
-                 key: Optional[str] = None,
+                 redis: Redis | None = None,
+                 key: str | None = None,
                  ) -> None:
         '''Initialize the HyperLogLog.  O(n)
 
@@ -149,8 +148,8 @@ def update(self, *objs: HyperLogLog | Iterable[RedisValues]) -> None:
 
     def union(self,
               *objs: Iterable[RedisValues],
-              redis: Optional[Redis] = None,
-              key: Optional[str] = None,
+              redis: Redis | None = None,
+              key: str | None = None,
               ) -> HyperLogLog:
         new_hll = self.__class__(redis=redis, key=key)
         new_hll.update(self, *objs)

pottery/list.py

@@ -32,7 +32,6 @@
 from typing import Callable
 from typing import Iterable
 from typing import List
-from typing import Optional
 from typing import cast
 
 from redis import Redis
@@ -82,8 +81,8 @@ def __slice_to_indices(self, slice_or_index: slice | int) -> range:
     def __init__(self,
                  iterable: Iterable[JSONTypes] = tuple(),
                  *,
-                 redis: Optional[Redis] = None,
-                 key: Optional[str] = None,
+                 redis: Redis | None = None,
+                 key: str | None = None,
                  ) -> None:
         'Initialize the RedisList.  O(n)'
         super().__init__(redis=redis, key=key)
@@ -251,7 +250,7 @@ def _insert(self,
 
     # Methods required for Raj's sanity:
 
-    def sort(self, *, key: Optional[str] = None, reverse: bool = False) -> None:
+    def sort(self, *, key: str | None = None, reverse: bool = False) -> None:
         'Sort the RedisList in place.  O(n)'
         if key is not None:
             raise NotImplementedError('sorting by key not implemented')
@@ -321,7 +320,7 @@ def extend(self, values: Iterable[JSONTypes]) -> None:
     __extend = extend
 
     # From collections.abc.MutableSequence:
-    def pop(self, index: Optional[int] = None) -> JSONTypes:
+    def pop(self, index: int | None = None) -> JSONTypes:
         with self._watch() as pipeline:
             len_ = len(self)
             if index and index >= len_:

pottery/nextid.py

@@ -36,7 +36,6 @@
 from typing import ClassVar
 from typing import Iterable
 from typing import List
-from typing import Optional
 from typing import Tuple
 from typing import Type
 from typing import cast
@@ -61,7 +60,7 @@ class _Scripts(Primitive):
 
     __slots__: Tuple[str, ...] = tuple()
 
-    _set_id_script: ClassVar[Optional[Script]] = None
+    _set_id_script: ClassVar[Script | None] = None
 
     def __init__(self,
                  *,

pottery/queue.py

@@ -16,11 +16,14 @@
 # --------------------------------------------------------------------------- #
 
 
+# TODO: When we drop support for Python 3.9, remove the following import.  We
+# only need it for X | Y union type annotations as of 2022-01-29.
+from __future__ import annotations
+
 import math
 import random
 import time
 from typing import ClassVar
-from typing import Optional
 from typing import Tuple
 from typing import cast
 
@@ -61,7 +64,7 @@ def empty(self) -> bool:
     def put(self,
             item: JSONTypes,
             block: bool = True,
-            timeout: Optional[float] = None,
+            timeout: float | None = None,
             ) -> None:
         '''Put the item on the queue.  O(1)
 
@@ -84,7 +87,7 @@ def put_nowait(self, item: JSONTypes) -> None:
 
     def get(self,
             block: bool = True,
-            timeout: Optional[float] = None,
+            timeout: float | None = None,
             ) -> JSONTypes:
         '''Remove and return an item from the queue.  O(1)