MNT: auto upgrade code base to Python 3.9

tests/unpin_requirements.py

@@ -1,6 +1,5 @@
 import re
 import sys
-from typing import List
 
 import tomli_w
 
@@ -12,7 +11,7 @@
 PINNED_VERSION_REGEXP = re.compile(r",?(<|<=|==)([0-9a-z]+\.?)+")
 
 
-def unpin_requirements(requirements: List[str]) -> List[str]:
+def unpin_requirements(requirements: list[str]) -> list[str]:
     return [re.sub(PINNED_VERSION_REGEXP, "", _) for _ in requirements]
 
 

yt/_maintenance/deprecation.py

@@ -1,7 +1,7 @@
 import warnings
 from functools import wraps
 from types import FunctionType
-from typing import Dict, Optional
+from typing import Optional
 
 
 def issue_deprecation_warning(
@@ -45,7 +45,7 @@ def issue_deprecation_warning(
     warnings.warn(msg, DeprecationWarning, stacklevel=stacklevel)
 
 
-def future_positional_only(positions2names: Dict[int, str], /, **depr_kwargs):
+def future_positional_only(positions2names: dict[int, str], /, **depr_kwargs):
     """Warn users when using a future positional-only argument as keyword.
     Note that positional-only arguments are available from Python 3.8
     See https://www.python.org/dev/peps/pep-0570/

yt/_typing.py

@@ -1,31 +1,31 @@
-from typing import List, Optional, Tuple, Union
+from typing import Optional, Union
 
 import unyt as un
 from numpy import ndarray
 
-FieldDescT = Tuple[str, Tuple[str, List[str], Optional[str]]]
-KnownFieldsT = Tuple[FieldDescT, ...]
+FieldDescT = tuple[str, tuple[str, list[str], Optional[str]]]
+KnownFieldsT = tuple[FieldDescT, ...]
 
 ParticleType = str
 FieldType = str
 FieldName = str
-FieldKey = Tuple[FieldType, FieldName]
+FieldKey = tuple[FieldType, FieldName]
 ImplicitFieldKey = FieldName
 AnyFieldKey = Union[FieldKey, ImplicitFieldKey]
-DomainDimensions = Union[Tuple[int, ...], List[int], ndarray]
+DomainDimensions = Union[tuple[int, ...], list[int], ndarray]
 
-ParticleCoordinateTuple = Tuple[
+ParticleCoordinateTuple = tuple[
     str,  # particle type
-    Tuple[ndarray, ndarray, ndarray],  # xyz
+    tuple[ndarray, ndarray, ndarray],  # xyz
     Union[float, ndarray],  # hsml
 ]
 
 # Geometry specific types
 AxisName = str
-AxisOrder = Tuple[AxisName, AxisName, AxisName]
+AxisOrder = tuple[AxisName, AxisName, AxisName]
 
 # types that can be converted to un.Unit
 Unit = Union[un.Unit, str]
 
 # types that can be converted to un.unyt_quantity
-Quantity = Union[un.unyt_quantity, Tuple[float, Unit]]
+Quantity = Union[un.unyt_quantity, tuple[float, Unit]]

yt/data_objects/data_containers.py

@@ -2,7 +2,7 @@
 import weakref
 from collections import defaultdict
 from contextlib import contextmanager
-from typing import TYPE_CHECKING, List, Optional, Tuple
+from typing import TYPE_CHECKING, Optional
 
 import numpy as np
 
@@ -66,14 +66,14 @@ class YTDataContainer(abc.ABC):
 
     _chunk_info = None
     _num_ghost_zones = 0
-    _con_args: Tuple[str, ...] = ()
+    _con_args: tuple[str, ...] = ()
     _skip_add = False
-    _container_fields: Tuple[AnyFieldKey, ...] = ()
-    _tds_attrs: Tuple[str, ...] = ()
-    _tds_fields: Tuple[str, ...] = ()
+    _container_fields: tuple[AnyFieldKey, ...] = ()
+    _tds_attrs: tuple[str, ...] = ()
+    _tds_fields: tuple[str, ...] = ()
     _field_cache = None
     _index = None
-    _key_fields: List[str]
+    _key_fields: list[str]
 
     def __init__(self, ds: Optional["Dataset"], field_parameters) -> None:
         """

yt/data_objects/index_subobjects/grid_patch.py

@@ -1,5 +1,4 @@
 import weakref
-from typing import List
 
 import numpy as np
 
@@ -270,7 +269,7 @@ def retrieve_ghost_zones(self, n_zones, fields, all_levels=False, smoothed=False
 
     def get_vertex_centered_data(
         self,
-        fields: List[FieldKey],
+        fields: list[FieldKey],
         smoothed: bool = True,
         no_ghost: bool = False,
     ):

yt/data_objects/index_subobjects/octree_subset.py

@@ -1,7 +1,6 @@
 from contextlib import contextmanager
 from functools import cached_property
 from itertools import product, repeat
-from typing import Tuple
 
 import numpy as np
 from unyt import unyt_array
@@ -39,7 +38,7 @@ class OctreeSubset(YTSelectionContainer):
     _num_ghost_zones = 0
     _type_name = "octree_subset"
     _skip_add = True
-    _con_args: Tuple[str, ...] = ("base_region", "domain", "ds")
+    _con_args: tuple[str, ...] = ("base_region", "domain", "ds")
     _domain_offset = 0
     _cell_count = -1
     _block_order = "C"

yt/data_objects/particle_filters.py

@@ -1,13 +1,12 @@
 import copy
 from contextlib import contextmanager
-from typing import Dict
 
 from yt.fields.field_info_container import NullFunc, TranslationFunc
 from yt.funcs import mylog
 from yt.utilities.exceptions import YTIllDefinedFilter
 
 # One to one mapping
-filter_registry: Dict[str, "ParticleFilter"] = {}
+filter_registry: dict[str, "ParticleFilter"] = {}
 
 
 class DummyFieldInfo:

yt/data_objects/selection_objects/data_selection_objects.py

@@ -4,7 +4,6 @@
 import uuid
 from collections import defaultdict
 from contextlib import contextmanager
-from typing import Tuple
 
 import numpy as np
 from more_itertools import always_iterable
@@ -1398,7 +1397,7 @@ def _get_bbox(self):
         """
         return self.ds.domain_left_edge, self.ds.domain_right_edge
 
-    def get_bbox(self) -> Tuple[unyt_array, unyt_array]:
+    def get_bbox(self) -> tuple[unyt_array, unyt_array]:
         """
         Return the bounding box for this data container.
         """

yt/data_objects/static_output.py

@@ -14,14 +14,8 @@
 from stat import ST_CTIME
 from typing import (
     Any,
-    DefaultDict,
-    Dict,
-    List,
     Literal,
     Optional,
-    Set,
-    Tuple,
-    Type,
     Union,
 )
 
@@ -89,11 +83,7 @@
 else:
     from typing_extensions import assert_never
 
-if sys.version_info >= (3, 9):
-    from collections.abc import MutableMapping
-else:
-    from typing import MutableMapping
-
+from collections.abc import MutableMapping
 
 # We want to support the movie format in the future.
 # When such a thing comes to pass, I'll move all the stuff that is constant up
@@ -178,26 +168,26 @@ def ireq(self, value):
 class Dataset(abc.ABC):
     default_fluid_type = "gas"
     default_field = ("gas", "density")
-    fluid_types: Tuple[FieldType, ...] = ("gas", "deposit", "index")
-    particle_types: Tuple[ParticleType, ...] = ("io",)  # By default we have an 'all'
-    particle_types_raw: Optional[Tuple[ParticleType, ...]] = ("io",)
+    fluid_types: tuple[FieldType, ...] = ("gas", "deposit", "index")
+    particle_types: tuple[ParticleType, ...] = ("io",)  # By default we have an 'all'
+    particle_types_raw: Optional[tuple[ParticleType, ...]] = ("io",)
     geometry: Geometry = Geometry.CARTESIAN
     coordinates = None
     storage_filename = None
-    particle_unions: Optional[Dict[ParticleType, ParticleUnion]] = None
-    known_filters: Optional[Dict[ParticleType, ParticleFilter]] = None
-    _index_class: Type[Index]
-    field_units: Optional[Dict[AnyFieldKey, Unit]] = None
+    particle_unions: Optional[dict[ParticleType, ParticleUnion]] = None
+    known_filters: Optional[dict[ParticleType, ParticleFilter]] = None
+    _index_class: type[Index]
+    field_units: Optional[dict[AnyFieldKey, Unit]] = None
     derived_field_list = requires_index("derived_field_list")
     fields = requires_index("fields")
-    conversion_factors: Optional[Dict[str, float]] = None
+    conversion_factors: Optional[dict[str, float]] = None
     # _instantiated represents an instantiation time (since Epoch)
     # the default is a place holder sentinel, falsy value
     _instantiated: float = 0
     _particle_type_counts = None
     _proj_type = "quad_proj"
     _ionization_label_format = "roman_numeral"
-    _determined_fields: Optional[Dict[str, List[FieldKey]]] = None
+    _determined_fields: Optional[dict[str, list[FieldKey]]] = None
     fields_detected = False
 
     # these are set in self._parse_parameter_file()
@@ -253,7 +243,7 @@ def __init__(
         self,
         filename: str,
         dataset_type: Optional[str] = None,
-        units_override: Optional[Dict[str, str]] = None,
+        units_override: Optional[dict[str, str]] = None,
         # valid unit_system values include all keys from unyt.unit_systems.unit_systems_registry + "code"
         unit_system: Literal[
             "cgs",
@@ -281,7 +271,7 @@ def __init__(
             return
         self.dataset_type = dataset_type
         self.conversion_factors = {}
-        self.parameters: Dict[str, Any] = {}
+        self.parameters: dict[str, Any] = {}
         self.region_expression = self.r = RegionExpression(self)
         self.known_filters = self.known_filters or {}
         self.particle_unions = self.particle_unions or {}
@@ -751,7 +741,7 @@ def setup_deprecated_fields(self):
     def _setup_coordinate_handler(self, axis_order: Optional[AxisOrder]) -> None:
         # backward compatibility layer:
         # turning off type-checker on a per-line basis
-        cls: Type[CoordinateHandler]
+        cls: type[CoordinateHandler]
 
         if isinstance(self.geometry, tuple):  # type: ignore [unreachable]
             issue_deprecation_warning(  # type: ignore [unreachable]
@@ -973,7 +963,7 @@ def _get_field_info(
             # https://github.com/yt-project/yt/issues/3381
             return field_info
 
-        def _are_ambiguous(candidates: List[FieldKey]) -> bool:
+        def _are_ambiguous(candidates: list[FieldKey]) -> bool:
             if len(candidates) < 2:
                 return False
 
@@ -996,7 +986,7 @@ def _are_ambiguous(candidates: List[FieldKey]) -> bool:
             elif all(ft in self.particle_types for ft in ftypes):
                 ptypes = ftypes
 
-                sub_types_list: List[Set[str]] = []
+                sub_types_list: list[set[str]] = []
                 for pt in ptypes:
                     if pt in self.particle_types_raw:
                         sub_types_list.append({pt})
@@ -1026,7 +1016,7 @@ def _get_field_info_helper(
         self,
         field: Union[FieldKey, ImplicitFieldKey, DerivedField],
         /,
-    ) -> Tuple[DerivedField, List[FieldKey]]:
+    ) -> tuple[DerivedField, list[FieldKey]]:
         self.index
 
         ftype: str
@@ -1041,7 +1031,7 @@ def _get_field_info_helper(
             raise YTFieldNotParseable(field)
 
         if ftype == "unknown":
-            candidates: List[FieldKey] = [
+            candidates: list[FieldKey] = [
                 (ft, fn) for ft, fn in self.field_info if fn == fname
             ]
 
@@ -1297,7 +1287,7 @@ def _assign_unit_system(
         # dimensions as amperes.
         mks_system = False
         mag_unit: Optional[unyt_quantity] = getattr(self, "magnetic_unit", None)
-        mag_dims: Optional[Set[Symbol]]
+        mag_dims: Optional[set[Symbol]]
         if mag_unit is not None:
             mag_dims = mag_unit.units.dimensions.free_symbols
         else:
@@ -2075,7 +2065,7 @@ class ParticleFile:
 
     start: Optional[int] = None
     end: Optional[int] = None
-    total_particles: Optional[DefaultDict[str, int]] = None
+    total_particles: Optional[defaultdict[str, int]] = None
 
     def __init__(self, ds, io, filename, file_id, range=None):
         self.ds = ds

yt/data_objects/time_series.py

@@ -5,7 +5,7 @@
 import weakref
 from abc import ABC, abstractmethod
 from functools import wraps
-from typing import Optional, Type
+from typing import Optional
 
 import numpy as np
 from more_itertools import always_iterable
@@ -146,7 +146,7 @@ class DatasetSeries:
     # this annotation should really be Optional[Type[Dataset]]
     # but we cannot import the yt.data_objects.static_output.Dataset
     # class here without creating a circular import for now
-    _dataset_cls: Optional[Type] = None
+    _dataset_cls: Optional[type] = None
 
     def __init_subclass__(cls, *args, **kwargs):
         super().__init_subclass__(*args, **kwargs)

yt/fields/derived_field.py

@@ -1,7 +1,8 @@
 import contextlib
 import inspect
 import re
-from typing import Iterable, Optional, Union
+from collections.abc import Iterable
+from typing import Optional, Union
 
 from more_itertools import always_iterable
 

yt/fields/domain_context.py

@@ -1,5 +1,4 @@
 import abc
-from typing import Tuple
 
 from yt._typing import FieldKey
 
@@ -12,8 +11,8 @@ def __init__(cls, name, b, d):
             type.__init__(cls, name, b, d)
             domain_context_registry[name] = cls
 
-    _known_fluid_fields: Tuple[FieldKey, ...]
-    _known_particle_fields: Tuple[FieldKey, ...]
+    _known_fluid_fields: tuple[FieldKey, ...]
+    _known_particle_fields: tuple[FieldKey, ...]
 
     def __init__(self, ds):
         self.ds = ds

yt/fields/field_detector.py

@@ -1,5 +1,5 @@
 from collections import defaultdict
-from typing import Tuple, Union
+from typing import Union
 
 import numpy as np
 
@@ -101,7 +101,7 @@ def _reshape_vals(self, arr):
             return arr
         return arr.reshape(self.ActiveDimensions, order="C")
 
-    def __missing__(self, item: Union[Tuple[str, str], str]):
+    def __missing__(self, item: Union[tuple[str, str], str]):
         from yt.fields.derived_field import NullFunc
 
         if not isinstance(item, tuple):
@@ -117,7 +117,7 @@ def __missing__(self, item: Union[Tuple[str, str], str]):
         # types not getting correctly identified.
         # Note that the *only* way this works is if we also fix our field
         # dependencies during checking.  Bug #627 talks about this.
-        _item: Tuple[str, str] = finfo.name
+        _item: tuple[str, str] = finfo.name
         if finfo is not None and finfo._function is not NullFunc:
             try:
                 for param, param_v in permute_params.items():