future annotations

pandas/_config/config.py

@@ -48,6 +48,8 @@
 
 """
 
+from __future__ import annotations
+
 from collections import namedtuple
 from contextlib import (
     ContextDecorator,
@@ -57,12 +59,7 @@
 from typing import (
     Any,
     Callable,
-    Dict,
     Iterable,
-    List,
-    Optional,
-    Tuple,
-    Type,
     cast,
 )
 import warnings
@@ -73,16 +70,16 @@
 RegisteredOption = namedtuple("RegisteredOption", "key defval doc validator cb")
 
 # holds deprecated option metadata
-_deprecated_options: Dict[str, DeprecatedOption] = {}
+_deprecated_options: dict[str, DeprecatedOption] = {}
 
 # holds registered option metadata
-_registered_options: Dict[str, RegisteredOption] = {}
+_registered_options: dict[str, RegisteredOption] = {}
 
 # holds the current values for registered options
-_global_config: Dict[str, Any] = {}
+_global_config: dict[str, Any] = {}
 
 # keys which have a special meaning
-_reserved_keys: List[str] = ["all"]
+_reserved_keys: list[str] = ["all"]
 
 
 class OptionError(AttributeError, KeyError):
@@ -194,7 +191,7 @@ def get_default_val(pat: str):
 class DictWrapper:
     """ provide attribute-style access to a nested dict"""
 
-    def __init__(self, d: Dict[str, Any], prefix: str = ""):
+    def __init__(self, d: dict[str, Any], prefix: str = ""):
         object.__setattr__(self, "d", d)
         object.__setattr__(self, "prefix", prefix)
 
@@ -428,8 +425,8 @@ def register_option(
     key: str,
     defval: object,
     doc: str = "",
-    validator: Optional[Callable[[Any], Any]] = None,
-    cb: Optional[Callable[[str], Any]] = None,
+    validator: Callable[[Any], Any] | None = None,
+    cb: Callable[[str], Any] | None = None,
 ) -> None:
     """
     Register an option in the package-wide pandas config object
@@ -500,7 +497,7 @@ def register_option(
 
 
 def deprecate_option(
-    key: str, msg: Optional[str] = None, rkey: Optional[str] = None, removal_ver=None
+    key: str, msg: str | None = None, rkey: str | None = None, removal_ver=None
 ) -> None:
     """
     Mark option `key` as deprecated, if code attempts to access this option,
@@ -547,7 +544,7 @@ def deprecate_option(
 # functions internal to the module
 
 
-def _select_options(pat: str) -> List[str]:
+def _select_options(pat: str) -> list[str]:
     """
     returns a list of keys matching `pat`
 
@@ -565,7 +562,7 @@ def _select_options(pat: str) -> List[str]:
     return [k for k in keys if re.search(pat, k, re.I)]
 
 
-def _get_root(key: str) -> Tuple[Dict[str, Any], str]:
+def _get_root(key: str) -> tuple[dict[str, Any], str]:
     path = key.split(".")
     cursor = _global_config
     for p in path[:-1]:
@@ -674,7 +671,7 @@ def pp_options_list(keys: Iterable[str], width=80, _print: bool = False):
     from itertools import groupby
     from textwrap import wrap
 
-    def pp(name: str, ks: Iterable[str]) -> List[str]:
+    def pp(name: str, ks: Iterable[str]) -> list[str]:
         pfx = "- " + name + ".[" if name else ""
         ls = wrap(
             ", ".join(ks),
@@ -687,7 +684,7 @@ def pp(name: str, ks: Iterable[str]) -> List[str]:
             ls[-1] = ls[-1] + "]"
         return ls
 
-    ls: List[str] = []
+    ls: list[str] = []
     singles = [x for x in sorted(keys) if x.find(".") < 0]
     if singles:
         ls += pp("", singles)
@@ -760,7 +757,7 @@ def inner(key: str, *args, **kwds):
 # arg in register_option
 
 
-def is_type_factory(_type: Type[Any]) -> Callable[[Any], None]:
+def is_type_factory(_type: type[Any]) -> Callable[[Any], None]:
     """
 
     Parameters
@@ -826,7 +823,7 @@ def inner(x) -> None:
     return inner
 
 
-def is_nonnegative_int(value: Optional[int]) -> None:
+def is_nonnegative_int(value: int | None) -> None:
     """
     Verify that value is None or a positive int.
 

pandas/_config/display.py

@@ -2,15 +2,16 @@
 Unopinionated display configuration.
 """
 
+from __future__ import annotations
+
 import locale
 import sys
-from typing import Optional
 
 from pandas._config import config as cf
 
 # -----------------------------------------------------------------------------
 # Global formatting options
-_initial_defencoding: Optional[str] = None
+_initial_defencoding: str | None = None
 
 
 def detect_console_encoding() -> str:

pandas/_testing/_io.py

@@ -1,11 +1,11 @@
+from __future__ import annotations
+
 import bz2
 from functools import wraps
 import gzip
 from typing import (
     Any,
     Callable,
-    Optional,
-    Tuple,
 )
 import zipfile
 
@@ -272,9 +272,7 @@ def can_connect(url, error_classes=None):
 # File-IO
 
 
-def round_trip_pickle(
-    obj: Any, path: Optional[FilePathOrBuffer] = None
-) -> FrameOrSeries:
+def round_trip_pickle(obj: Any, path: FilePathOrBuffer | None = None) -> FrameOrSeries:
     """
     Pickle an object and then read it again.
 
@@ -298,7 +296,7 @@ def round_trip_pickle(
         return pd.read_pickle(temp_path)
 
 
-def round_trip_pathlib(writer, reader, path: Optional[str] = None):
+def round_trip_pathlib(writer, reader, path: str | None = None):
     """
     Write an object to file specified by a pathlib.Path and read it back
 
@@ -327,7 +325,7 @@ def round_trip_pathlib(writer, reader, path: Optional[str] = None):
     return obj
 
 
-def round_trip_localpath(writer, reader, path: Optional[str] = None):
+def round_trip_localpath(writer, reader, path: str | None = None):
     """
     Write an object to file specified by a py.path LocalPath and read it back.
 
@@ -375,7 +373,7 @@ def write_to_compressed(compression, path, data, dest="test"):
     ------
     ValueError : An invalid compression value was passed in.
     """
-    args: Tuple[Any, ...] = (data,)
+    args: tuple[Any, ...] = (data,)
     mode = "wb"
     method = "write"
     compress_method: Callable

pandas/_testing/_warnings.py

@@ -1,22 +1,22 @@
+from __future__ import annotations
+
 from contextlib import contextmanager
 import re
 from typing import (
-    Optional,
     Sequence,
     Type,
-    Union,
     cast,
 )
 import warnings
 
 
 @contextmanager
 def assert_produces_warning(
-    expected_warning: Optional[Union[Type[Warning], bool]] = Warning,
+    expected_warning: type[Warning] | bool | None = Warning,
     filter_level="always",
     check_stacklevel: bool = True,
     raise_on_extra_warnings: bool = True,
-    match: Optional[str] = None,
+    match: str | None = None,
 ):
     """
     Context manager for running code expected to either raise a specific
@@ -99,8 +99,8 @@ class for all warnings. To check that no warning is returned,
 def _assert_caught_expected_warning(
     *,
     caught_warnings: Sequence[warnings.WarningMessage],
-    expected_warning: Type[Warning],
-    match: Optional[str],
+    expected_warning: type[Warning],
+    match: str | None,
     check_stacklevel: bool,
 ) -> None:
     """Assert that there was the expected warning among the caught warnings."""
@@ -135,7 +135,7 @@ def _assert_caught_expected_warning(
 def _assert_caught_no_extra_warnings(
     *,
     caught_warnings: Sequence[warnings.WarningMessage],
-    expected_warning: Optional[Union[Type[Warning], bool]],
+    expected_warning: type[Warning] | bool | None,
 ) -> None:
     """Assert that no extra warnings apart from the expected ones are caught."""
     extra_warnings = []
@@ -157,7 +157,7 @@ def _assert_caught_no_extra_warnings(
 
 def _is_unexpected_warning(
     actual_warning: warnings.WarningMessage,
-    expected_warning: Optional[Union[Type[Warning], bool]],
+    expected_warning: type[Warning] | bool | None,
 ) -> bool:
     """Check if the actual warning issued is unexpected."""
     if actual_warning and not expected_warning:

pandas/_testing/asserters.py

@@ -1,7 +1,6 @@
-from typing import (
-    Union,
-    cast,
-)
+from __future__ import annotations
+
+from typing import cast
 import warnings
 
 import numpy as np
@@ -56,8 +55,8 @@
 def assert_almost_equal(
     left,
     right,
-    check_dtype: Union[bool, str] = "equiv",
-    check_less_precise: Union[bool, int, NoDefault] = no_default,
+    check_dtype: bool | str = "equiv",
+    check_less_precise: bool | int | NoDefault = no_default,
     rtol: float = 1.0e-5,
     atol: float = 1.0e-8,
     **kwargs,
@@ -169,7 +168,7 @@ def assert_almost_equal(
         )
 
 
-def _get_tol_from_less_precise(check_less_precise: Union[bool, int]) -> float:
+def _get_tol_from_less_precise(check_less_precise: bool | int) -> float:
     """
     Return the tolerance equivalent to the deprecated `check_less_precise`
     parameter.
@@ -247,9 +246,9 @@ def assert_dict_equal(left, right, compare_keys: bool = True):
 def assert_index_equal(
     left: Index,
     right: Index,
-    exact: Union[bool, str] = "equiv",
+    exact: bool | str = "equiv",
     check_names: bool = True,
-    check_less_precise: Union[bool, int, NoDefault] = no_default,
+    check_less_precise: bool | int | NoDefault = no_default,
     check_exact: bool = True,
     check_categorical: bool = True,
     check_order: bool = True,
@@ -429,7 +428,7 @@ def _get_ilevel_values(index, level):
             assert_categorical_equal(left._values, right._values, obj=f"{obj} category")
 
 
-def assert_class_equal(left, right, exact: Union[bool, str] = True, obj="Input"):
+def assert_class_equal(left, right, exact: bool | str = True, obj="Input"):
     """
     Checks classes are equal.
     """

pandas/_testing/contexts.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from contextlib import contextmanager
 import os
 from pathlib import Path
@@ -8,7 +10,6 @@
 from typing import (
     IO,
     Any,
-    Union,
 )
 
 import numpy as np
@@ -111,7 +112,7 @@ def ensure_clean(filename=None, return_filelike: bool = False, **kwargs: Any):
 
     path.touch()
 
-    handle_or_str: Union[str, IO] = str(path)
+    handle_or_str: str | IO = str(path)
     if return_filelike:
         kwargs.setdefault("mode", "w+b")
         handle_or_str = open(path, **kwargs)

pandas/compat/_optional.py

@@ -1,8 +1,9 @@
+from __future__ import annotations
+
 import distutils.version
 import importlib
 import sys
 import types
-from typing import Optional
 import warnings
 
 # Update install.rst when updating versions!
@@ -63,7 +64,7 @@ def import_optional_dependency(
     name: str,
     extra: str = "",
     errors: str = "raise",
-    min_version: Optional[str] = None,
+    min_version: str | None = None,
 ):
     """
     Import an optional dependency.

pandas/core/accessor.py

@@ -4,33 +4,30 @@
 that can be mixed into or pinned onto other pandas classes.
 
 """
-from typing import (
-    FrozenSet,
-    List,
-    Set,
-)
+from __future__ import annotations
+
 import warnings
 
 from pandas.util._decorators import doc
 
 
 class DirNamesMixin:
-    _accessors: Set[str] = set()
-    _hidden_attrs: FrozenSet[str] = frozenset()
+    _accessors: set[str] = set()
+    _hidden_attrs: frozenset[str] = frozenset()
 
-    def _dir_deletions(self) -> Set[str]:
+    def _dir_deletions(self) -> set[str]:
         """
         Delete unwanted __dir__ for this object.
         """
         return self._accessors | self._hidden_attrs
 
-    def _dir_additions(self) -> Set[str]:
+    def _dir_additions(self) -> set[str]:
         """
         Add additional __dir__ for this object.
         """
         return {accessor for accessor in self._accessors if hasattr(self, accessor)}
 
-    def __dir__(self) -> List[str]:
+    def __dir__(self) -> list[str]:
         """
         Provide method name lookup and completion.