TYP: use from __future__ import annotations more (#41892)

Author: simonjayhawkins

pandas/io/json/_json.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from abc import (
     ABC,
     abstractmethod,
@@ -10,10 +12,6 @@
     Any,
     Callable,
     Mapping,
-    Optional,
-    Tuple,
-    Type,
-    Union,
 )
 
 import numpy as np
@@ -78,12 +76,12 @@
 def to_json(
     path_or_buf,
     obj: NDFrame,
-    orient: Optional[str] = None,
+    orient: str | None = None,
     date_format: str = "epoch",
     double_precision: int = 10,
     force_ascii: bool = True,
     date_unit: str = "ms",
-    default_handler: Optional[Callable[[Any], JSONSerializable]] = None,
+    default_handler: Callable[[Any], JSONSerializable] | None = None,
     lines: bool = False,
     compression: CompressionOptions = "infer",
     index: bool = True,
@@ -102,7 +100,7 @@ def to_json(
     if orient == "table" and isinstance(obj, Series):
         obj = obj.to_frame(name=obj.name or "values")
 
-    writer: Type[Writer]
+    writer: type[Writer]
     if orient == "table" and isinstance(obj, DataFrame):
         writer = JSONTableWriter
     elif isinstance(obj, Series):
@@ -143,13 +141,13 @@ class Writer(ABC):
     def __init__(
         self,
         obj,
-        orient: Optional[str],
+        orient: str | None,
         date_format: str,
         double_precision: int,
         ensure_ascii: bool,
         date_unit: str,
         index: bool,
-        default_handler: Optional[Callable[[Any], JSONSerializable]] = None,
+        default_handler: Callable[[Any], JSONSerializable] | None = None,
         indent: int = 0,
     ):
         self.obj = obj
@@ -187,7 +185,7 @@ def write(self):
 
     @property
     @abstractmethod
-    def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
+    def obj_to_write(self) -> NDFrame | Mapping[IndexLabel, Any]:
         """Object to write in JSON format."""
         pass
 
@@ -196,7 +194,7 @@ class SeriesWriter(Writer):
     _default_orient = "index"
 
     @property
-    def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
+    def obj_to_write(self) -> NDFrame | Mapping[IndexLabel, Any]:
         if not self.index and self.orient == "split":
             return {"name": self.obj.name, "data": self.obj.values}
         else:
@@ -211,7 +209,7 @@ class FrameWriter(Writer):
     _default_orient = "columns"
 
     @property
-    def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
+    def obj_to_write(self) -> NDFrame | Mapping[IndexLabel, Any]:
         if not self.index and self.orient == "split":
             obj_to_write = self.obj.to_dict(orient="split")
             del obj_to_write["index"]
@@ -243,13 +241,13 @@ class JSONTableWriter(FrameWriter):
     def __init__(
         self,
         obj,
-        orient: Optional[str],
+        orient: str | None,
         date_format: str,
         double_precision: int,
         ensure_ascii: bool,
         date_unit: str,
         index: bool,
-        default_handler: Optional[Callable[[Any], JSONSerializable]] = None,
+        default_handler: Callable[[Any], JSONSerializable] | None = None,
         indent: int = 0,
     ):
         """
@@ -313,7 +311,7 @@ def __init__(
         self.index = index
 
     @property
-    def obj_to_write(self) -> Union[NDFrame, Mapping[IndexLabel, Any]]:
+    def obj_to_write(self) -> NDFrame | Mapping[IndexLabel, Any]:
         return {"schema": self.schema, "data": self.obj}
 
 
@@ -326,19 +324,19 @@ def read_json(
     path_or_buf=None,
     orient=None,
     typ="frame",
-    dtype: Optional[DtypeArg] = None,
+    dtype: DtypeArg | None = None,
     convert_axes=None,
     convert_dates=True,
     keep_default_dates: bool = True,
     numpy: bool = False,
     precise_float: bool = False,
     date_unit=None,
     encoding=None,
-    encoding_errors: Optional[str] = "strict",
+    encoding_errors: str | None = "strict",
     lines: bool = False,
-    chunksize: Optional[int] = None,
+    chunksize: int | None = None,
     compression: CompressionOptions = "infer",
-    nrows: Optional[int] = None,
+    nrows: int | None = None,
     storage_options: StorageOptions = None,
 ):
     """
@@ -639,11 +637,11 @@ def __init__(
         date_unit,
         encoding,
         lines: bool,
-        chunksize: Optional[int],
+        chunksize: int | None,
         compression: CompressionOptions,
-        nrows: Optional[int],
+        nrows: int | None,
         storage_options: StorageOptions = None,
-        encoding_errors: Optional[str] = "strict",
+        encoding_errors: str | None = "strict",
     ):
 
         self.orient = orient
@@ -663,7 +661,7 @@ def __init__(
         self.nrows_seen = 0
         self.nrows = nrows
         self.encoding_errors = encoding_errors
-        self.handles: Optional[IOHandles] = None
+        self.handles: IOHandles | None = None
 
         if self.chunksize is not None:
             self.chunksize = validate_integer("chunksize", self.chunksize, 1)
@@ -816,7 +814,7 @@ def __exit__(self, exc_type, exc_value, traceback):
 
 
 class Parser:
-    _split_keys: Tuple[str, ...]
+    _split_keys: tuple[str, ...]
     _default_orient: str
 
     _STAMP_UNITS = ("s", "ms", "us", "ns")
@@ -831,7 +829,7 @@ def __init__(
         self,
         json,
         orient,
-        dtype: Optional[DtypeArg] = None,
+        dtype: DtypeArg | None = None,
         convert_axes=True,
         convert_dates=True,
         keep_default_dates=False,
@@ -865,7 +863,7 @@ def __init__(
         self.convert_dates = convert_dates
         self.date_unit = date_unit
         self.keep_default_dates = keep_default_dates
-        self.obj: Optional[FrameOrSeriesUnion] = None
+        self.obj: FrameOrSeriesUnion | None = None
 
     def check_keys_split(self, decoded):
         """

pandas/plotting/_matplotlib/converter.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import contextlib
 import datetime as pydt
 from datetime import (
@@ -6,13 +8,7 @@
     tzinfo,
 )
 import functools
-from typing import (
-    Any,
-    Dict,
-    List,
-    Optional,
-    Tuple,
-)
+from typing import Any
 
 from dateutil.relativedelta import relativedelta
 import matplotlib.dates as dates
@@ -169,7 +165,7 @@ def convert(value, unit, axis):
         return value
 
     @staticmethod
-    def axisinfo(unit, axis) -> Optional[units.AxisInfo]:
+    def axisinfo(unit, axis) -> units.AxisInfo | None:
         if unit != "time":
             return None
 
@@ -319,7 +315,7 @@ def try_parse(values):
         return values
 
     @staticmethod
-    def axisinfo(unit: Optional[tzinfo], axis) -> units.AxisInfo:
+    def axisinfo(unit: tzinfo | None, axis) -> units.AxisInfo:
         """
         Return the :class:`~matplotlib.units.AxisInfo` for *unit*.
 
@@ -447,7 +443,7 @@ def autoscale(self):
         return self.nonsingular(vmin, vmax)
 
 
-def _from_ordinal(x, tz: Optional[tzinfo] = None) -> datetime:
+def _from_ordinal(x, tz: tzinfo | None = None) -> datetime:
     ix = int(x)
     dt = datetime.fromordinal(ix)
     remainder = float(x) - ix
@@ -476,7 +472,7 @@ def _from_ordinal(x, tz: Optional[tzinfo] = None) -> datetime:
 # -------------------------------------------------------------------------
 
 
-def _get_default_annual_spacing(nyears) -> Tuple[int, int]:
+def _get_default_annual_spacing(nyears) -> tuple[int, int]:
     """
     Returns a default spacing between consecutive ticks for annual data.
     """
@@ -1027,8 +1023,8 @@ def __init__(
         freq = to_offset(freq)
         self.format = None
         self.freq = freq
-        self.locs: List[Any] = []  # unused, for matplotlib compat
-        self.formatdict: Optional[Dict[Any, Any]] = None
+        self.locs: list[Any] = []  # unused, for matplotlib compat
+        self.formatdict: dict[Any, Any] | None = None
         self.isminor = minor_locator
         self.isdynamic = dynamic_mode
         self.offset = 0

pandas/tests/extension/base/ops.py

@@ -1,7 +1,4 @@
-from typing import (
-    Optional,
-    Type,
-)
+from __future__ import annotations
 
 import pytest
 
@@ -67,10 +64,10 @@ class BaseArithmeticOpsTests(BaseOpsUtil):
     * divmod_exc = TypeError
     """
 
-    series_scalar_exc: Optional[Type[TypeError]] = TypeError
-    frame_scalar_exc: Optional[Type[TypeError]] = TypeError
-    series_array_exc: Optional[Type[TypeError]] = TypeError
-    divmod_exc: Optional[Type[TypeError]] = TypeError
+    series_scalar_exc: type[TypeError] | None = TypeError
+    frame_scalar_exc: type[TypeError] | None = TypeError
+    series_array_exc: type[TypeError] | None = TypeError
+    divmod_exc: type[TypeError] | None = TypeError
 
     def test_arith_series_with_scalar(self, data, all_arithmetic_operators):
         # series & scalar

pandas/tests/io/parser/conftest.py

@@ -1,8 +1,6 @@
+from __future__ import annotations
+
 import os
-from typing import (
-    List,
-    Optional,
-)
 
 import pytest
 
@@ -13,9 +11,9 @@
 
 
 class BaseParser:
-    engine: Optional[str] = None
+    engine: str | None = None
     low_memory = True
-    float_precision_choices: List[Optional[str]] = []
+    float_precision_choices: list[str | None] = []
 
     def update_kwargs(self, kwargs):
         kwargs = kwargs.copy()

pandas/tests/tseries/offsets/common.py

@@ -1,11 +1,9 @@
 """
 Assertion helpers and base class for offsets tests
 """
+from __future__ import annotations
+
 from datetime import datetime
-from typing import (
-    Optional,
-    Type,
-)
 
 from dateutil.tz.tz import tzlocal
 import pytest
@@ -61,7 +59,7 @@ class WeekDay:
 
 
 class Base:
-    _offset: Optional[Type[DateOffset]] = None
+    _offset: type[DateOffset] | None = None
     d = Timestamp(datetime(2008, 1, 2))
 
     timezones = [