Upgrade to Python 3.10 using pyupgrade

The primary change is updating type hints to use PEP 604 features:
`X | Y` over `Union[X, Y]` and `X | None` over `Optional[X]`.

Author: mx-moth

docs/developing/grass.py

@@ -2,7 +2,6 @@
 import enum
 from collections.abc import Hashable, Sequence
 from functools import cached_property
-from typing import Optional
 
 import numpy
 import xarray
@@ -33,7 +32,7 @@ class Grass(DimensionConvention[GrassGridKind, GrassIndex]):
     default_grid_kind = GrassGridKind.field
 
     @classmethod
-    def check_dataset(cls, dataset: xarray.Dataset) -> Optional[int]:
+    def check_dataset(cls, dataset: xarray.Dataset) -> int | None:
         # A Grass dataset is recognised by the 'Conventions' global attribute
         if dataset.attrs['Conventions'] == 'Grass 1.0':
             return Specificity.HIGH

docs/roles.py

@@ -1,6 +1,6 @@
 import re
-from collections.abc import Iterable
-from typing import Callable, cast
+from collections.abc import Callable, Iterable
+from typing import cast
 
 import yaml
 from docutils import nodes, utils
@@ -81,7 +81,7 @@ class Citation(Directive):
 
     def load_citation_file(self) -> dict:
         citation_file = self.options['citation_file']
-        with open(citation_file, 'r') as f:
+        with open(citation_file) as f:
             return cast(dict, yaml.load(f, yaml.Loader))
 
     def run(self) -> list[nodes.Node]:

scripts/min_deps_check.py

@@ -55,7 +55,7 @@ def parse_requirements(
 
     Yield (package name, major version, minor version, patch version)
     """
-    for line_number, line in enumerate(open(fname, 'r'), start=1):
+    for line_number, line in enumerate(open(fname), start=1):
         if '#' in line:
             line = line[:line.index('#')]
         line = line.strip()

scripts/release.py

@@ -6,7 +6,6 @@
 import shlex
 import subprocess
 import sys
-from typing import Optional
 
 PROJECT = pathlib.Path(__file__).parent.parent
 
@@ -29,7 +28,7 @@
 
 
 def main(
-    args: Optional[list[str]] = None,
+    args: list[str] | None = None,
 ) -> None:
     parser = argparse.ArgumentParser()
     add_options(parser)
@@ -222,7 +221,7 @@ def output(*args: str) -> bytes:
 
 def yn(
     prompt: str,
-    default: Optional[bool] = None,
+    default: bool | None = None,
 ) -> bool:
     examples = {True: '[Yn]', False: '[yN]', None: '[yn]'}[default]
     prompt = f'{prompt.strip()} {examples} '

src/emsarray/cli/command.py

@@ -1,6 +1,5 @@
 import abc
 import argparse
-from typing import Optional
 
 from emsarray.cli import utils
 
@@ -24,11 +23,11 @@ def name(self) -> str:
 
     #: A short description of what this subcommand does,
     #: shown as part of the usage message for the base command.
-    help: Optional[str] = None
+    help: str | None = None
 
     #: A longer description of what this subcommand does,
     #: shown as part of the usage message for this subcommand.
-    description: Optional[str] = None
+    description: str | None = None
 
     def add_parser(self, subparsers: argparse._SubParsersAction) -> None:
         parser = subparsers.add_parser(

src/emsarray/cli/commands/export_geometry.py

@@ -1,7 +1,7 @@
 import argparse
 import logging
+from collections.abc import Callable
 from pathlib import Path
-from typing import Callable
 
 import xarray
 

src/emsarray/cli/commands/plot.py

@@ -1,8 +1,9 @@
 import argparse
 import functools
 import logging
+from collections.abc import Callable
 from pathlib import Path
-from typing import Any, Callable, Optional, TypeVar
+from typing import Any, TypeVar
 
 import emsarray
 from emsarray.cli import BaseCommand, CommandException
@@ -28,7 +29,7 @@ def __init__(
         dest: str,
         *,
         value_type: Callable = str,
-        default: Optional[dict[str, Any]] = None,
+        default: dict[str, Any] | None = None,
         **kwargs: Any,
     ):
         if default is None:
@@ -42,7 +43,7 @@ def __call__(
         parser: argparse.ArgumentParser,
         namespace: argparse.Namespace,
         values: Any,
-        option_string: Optional[str] = None,
+        option_string: str | None = None,
     ) -> None:
         super().__call__
         holder = getattr(namespace, self.dest, {})

src/emsarray/cli/utils.py

@@ -9,10 +9,10 @@
 import re
 import sys
 import textwrap
-from collections.abc import Iterator
+from collections.abc import Callable, Iterator
 from functools import wraps
 from pathlib import Path
-from typing import Callable, Optional, Protocol
+from typing import Protocol
 
 from shapely.geometry import box, shape
 from shapely.geometry.base import BaseGeometry
@@ -30,7 +30,7 @@
 class MainCallable(Protocol):
     def __call__(
         self,
-        argv: Optional[list[str]] = None,
+        argv: list[str] | None = None,
         handle_errors: bool = True,
     ) -> None:
         ...
@@ -112,7 +112,7 @@ def decorator(
     ) -> MainCallable:
         @wraps(fn)
         def wrapper(
-            argv: Optional[list[str]] = None,
+            argv: list[str] | None = None,
             handle_errors: bool = True,
         ) -> None:
             parser = argparse.ArgumentParser(
@@ -172,7 +172,7 @@ def nice_console_errors() -> Iterator:
 
 class DoubleNewlineDescriptionFormatter(argparse.HelpFormatter):
     def _fill_text(self, text: str, width: int, indent: str) -> str:
-        fill_text = super(DoubleNewlineDescriptionFormatter, self)._fill_text
+        fill_text = super()._fill_text
 
         return '\n\n'.join(
             fill_text(paragraph, width, indent)

src/emsarray/compat/shapely.py

@@ -1,6 +1,6 @@
 import warnings
 from collections.abc import Iterable
-from typing import Generic, TypeVar, Union, cast
+from typing import Generic, TypeVar, cast
 
 import numpy
 import shapely
@@ -31,7 +31,7 @@ class SpatialIndex(Generic[T]):
 
     def __init__(
         self,
-        items: Union[numpy.ndarray, Iterable[tuple[BaseGeometry, T]]],
+        items: numpy.ndarray | Iterable[tuple[BaseGeometry, T]],
     ):
         self.items = numpy.array(items, dtype=self.dtype)
 

src/emsarray/conventions/_base.py

@@ -3,11 +3,9 @@
 import enum
 import logging
 import warnings
-from collections.abc import Hashable, Iterable, Sequence
+from collections.abc import Callable, Hashable, Iterable, Sequence
 from functools import cached_property
-from typing import (
-    TYPE_CHECKING, Any, Callable, Generic, Optional, TypeVar, Union, cast
-)
+from typing import TYPE_CHECKING, Any, Generic, TypeVar, cast
 
 import numpy
 import xarray
@@ -166,7 +164,7 @@ def check_validity(cls, dataset: xarray.Dataset) -> None:
 
     @classmethod
     @abc.abstractmethod
-    def check_dataset(cls, dataset: xarray.Dataset) -> Optional[int]:
+    def check_dataset(cls, dataset: xarray.Dataset) -> int | None:
         """
         Check if a dataset uses this convention.
 
@@ -582,7 +580,7 @@ def wind_index(
         self,
         linear_index: int,
         *,
-        grid_kind: Optional[GridKind] = None,
+        grid_kind: GridKind | None = None,
     ) -> Index:
         """Convert a linear index to a conventnion native index.
 
@@ -635,7 +633,7 @@ def wind_index(
     def unravel_index(
         self,
         linear_index: int,
-        grid_kind: Optional[GridKind] = None,
+        grid_kind: GridKind | None = None,
     ) -> Index:
         """An alias for :meth:`Convention.wind_index()`.
 
@@ -772,7 +770,7 @@ def ravel(
         self,
         data_array: xarray.DataArray,
         *,
-        linear_dimension: Optional[Hashable] = None,
+        linear_dimension: Hashable | None = None,
     ) -> xarray.DataArray:
         """
         Flatten the surface dimensions of a :class:`~xarray.DataArray`,
@@ -815,9 +813,9 @@ def wind(
         self,
         data_array: xarray.DataArray,
         *,
-        grid_kind: Optional[GridKind] = None,
-        axis: Optional[int] = None,
-        linear_dimension: Optional[Hashable] = None,
+        grid_kind: GridKind | None = None,
+        axis: int | None = None,
+        linear_dimension: Hashable | None = None,
     ) -> xarray.DataArray:
         """
         Wind a flattened :class:`~xarray.DataArray`
@@ -935,9 +933,9 @@ def data_crs(self) -> 'CRS':
     def plot_on_figure(
         self,
         figure: 'Figure',
-        scalar: Optional[DataArrayOrName] = None,
-        vector: Optional[tuple[DataArrayOrName, DataArrayOrName]] = None,
-        title: Optional[str] = None,
+        scalar: DataArrayOrName | None = None,
+        vector: tuple[DataArrayOrName, DataArrayOrName] | None = None,
+        title: str | None = None,
         **kwargs: Any,
     ) -> None:
         """Plot values for a :class:`~xarray.DataArray`
@@ -1015,10 +1013,10 @@ def plot(self, *args: Any, **kwargs: Any) -> None:
     def animate_on_figure(
         self,
         figure: 'Figure',
-        scalar: Optional[DataArrayOrName] = None,
-        vector: Optional[tuple[DataArrayOrName, DataArrayOrName]] = None,
-        coordinate: Optional[DataArrayOrName] = None,
-        title: Optional[Union[str, Callable[[Any], str]]] = None,
+        scalar: DataArrayOrName | None = None,
+        vector: tuple[DataArrayOrName, DataArrayOrName] | None = None,
+        coordinate: DataArrayOrName | None = None,
+        title: str | Callable[[Any], str] | None = None,
         **kwargs: Any,
     ) -> 'FuncAnimation':
         """
@@ -1115,7 +1113,7 @@ def animate_on_figure(
     @utils.timed_func
     def make_poly_collection(
         self,
-        data_array: Optional[DataArrayOrName] = None,
+        data_array: DataArrayOrName | None = None,
         **kwargs: Any,
     ) -> 'PolyCollection':
         """
@@ -1192,7 +1190,7 @@ def make_poly_collection(
 
     def make_patch_collection(
         self,
-        data_array: Optional[DataArrayOrName] = None,
+        data_array: DataArrayOrName | None = None,
         **kwargs: Any,
     ) -> 'PolyCollection':
         warnings.warn(
@@ -1206,8 +1204,8 @@ def make_patch_collection(
     def make_quiver(
         self,
         axes: 'Axes',
-        u: Optional[DataArrayOrName] = None,
-        v: Optional[DataArrayOrName] = None,
+        u: DataArrayOrName | None = None,
+        v: DataArrayOrName | None = None,
         **kwargs: Any,
     ) -> 'Quiver':
         """
@@ -1238,7 +1236,7 @@ def make_quiver(
         # sometimes preferring to fill them in later,
         # so `u` and `v` are optional.
         # If they are not provided, we set default quiver values of `numpy.nan`.
-        values: Union[tuple[numpy.ndarray, numpy.ndarray], tuple[float, float]]
+        values: tuple[numpy.ndarray, numpy.ndarray] | tuple[float, float]
         values = numpy.nan, numpy.nan
 
         if u is not None and v is not None:
@@ -1331,7 +1329,7 @@ def mask(self) -> numpy.ndarray:
         return cast(numpy.ndarray, mask)
 
     @cached_property
-    def geometry(self) -> Union[Polygon, MultiPolygon]:
+    def geometry(self) -> Polygon | MultiPolygon:
         """
         A :class:`shapely.Polygon` or :class:`shapely.MultiPolygon` that represents
         the geometry of the entire dataset.
@@ -1438,7 +1436,7 @@ def spatial_index(self) -> SpatialIndex[SpatialIndexItem[Index]]:
     def get_index_for_point(
         self,
         point: Point,
-    ) -> Optional[SpatialIndexItem[Index]]:
+    ) -> SpatialIndexItem[Index] | None:
         """
         Find the index for a :class:`~shapely.Point` in the dataset.
 
@@ -1761,8 +1759,8 @@ def ocean_floor(self) -> xarray.Dataset:
     def normalize_depth_variables(
         self,
         *,
-        positive_down: Optional[bool] = None,
-        deep_to_shallow: Optional[bool] = None,
+        positive_down: bool | None = None,
+        deep_to_shallow: bool | None = None,
     ) -> xarray.Dataset:
         """An alias for :func:`emsarray.operations.depth.normalize_depth_variables`"""
         return depth.normalize_depth_variables(
@@ -1895,7 +1893,7 @@ def wind_index(
         self,
         linear_index: int,
         *,
-        grid_kind: Optional[GridKind] = None,
+        grid_kind: GridKind | None = None,
     ) -> Index:
         if grid_kind is None:
             grid_kind = self.default_grid_kind
@@ -1907,7 +1905,7 @@ def ravel(
         self,
         data_array: xarray.DataArray,
         *,
-        linear_dimension: Optional[Hashable] = None,
+        linear_dimension: Hashable | None = None,
     ) -> xarray.DataArray:
         kind = self.get_grid_kind(data_array)
         dimensions = self.grid_dimensions[kind]
@@ -1919,9 +1917,9 @@ def wind(
         self,
         data_array: xarray.DataArray,
         *,
-        grid_kind: Optional[GridKind] = None,
-        axis: Optional[int] = None,
-        linear_dimension: Optional[Hashable] = None,
+        grid_kind: GridKind | None = None,
+        axis: int | None = None,
+        linear_dimension: Hashable | None = None,
     ) -> xarray.DataArray:
         if axis is not None:
             linear_dimension = data_array.dims[axis]