DEP: drop support for CPython 3.8

.git-blame-ignore-revs

@@ -44,3 +44,6 @@ ef783151bfd7c6777fa25e9e06f95fe47653b3aa
 
 # apply linting to ipynb files
 ec8bb45ea1603f3862041fa9e8ec274afd9bbbfd
+
+# auto upgrade typing idioms from Python 3.8 to 3.9
+4cfd370a8445abd4620e3853c2c047ee3d649fd7

.github/workflows/build-test.yaml

@@ -33,7 +33,7 @@ jobs:
         test-runner: [pytest]
         include:
           - os: ubuntu-latest
-            python-version: '3.8'
+            python-version: '3.9'
             dependencies: minimal
             tests-type: unit
             test-runner: pytest

.github/workflows/type-checking.yaml

@@ -29,10 +29,10 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v4
       with:
-        # run with oldest support python version
+        # run with oldest supported python version
         # so that we always get compatible versions of
         # core dependencies at type-check time
-        python-version: '3.8'
+        python-version: '3.9'
 
     - name: Build
       run: |

.github/workflows/wheels.yaml

@@ -35,7 +35,7 @@ jobs:
         with:
           output-dir: dist
         env:
-          CIBW_BUILD: "cp38-* cp39-* cp310-* cp311-* cp312-*"
+          CIBW_BUILD: "cp39-* cp310-* cp311-* cp312-*"
           CIBW_SKIP: "*-musllinux_*"  #  numpy doesn't have wheels for musllinux so we can't build some quickly and without bloating
           CIBW_ARCHS_LINUX: "x86_64"
           CIBW_ARCHS_MACOS: x86_64 arm64

pyproject.toml

@@ -2,14 +2,12 @@
 # keep in sync with .github/workflows/wheels.yaml
 requires = [
   "setuptools>=61.2",
-  "importlib_resources>=1.3;python_version < '3.9'",
 
   # see https://github.com/yt-project/yt/issues/4044
   "Cython>=3.0, <3.1",
 
   # TODO: simplify requirement after numpy 1.26.0 final is released
-  "oldest-supported-numpy ; python_version < '3.9'",
-  "numpy>=1.25, <2.0 ; python_version >= '3.9' and python_version < '3.12.0rc1'",
+  "numpy>=1.25, <2.0 ; python_version < '3.12.0rc1'",
   "numpy>=1.26.0b1, <2.0; python_version >= '3.12.0rc1'",
 
   # TODO: simplify requirement after ewah-bool-utils 1.1.0 final is released
@@ -37,7 +35,6 @@ classifiers = [
     "Programming Language :: C",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3 :: Only",
-    "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
@@ -48,23 +45,19 @@ classifiers = [
 keywords = [
     "astronomy astrophysics visualization amr adaptivemeshrefinement",
 ]
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 dependencies = [
     "cmyt>=1.1.2",
     "ewah-bool-utils>=1.0.2",
     "ipywidgets>=8.0.0",
     "matplotlib>=3.5",
     "more-itertools>=8.4",
-    # when Python 3.8 is dropped, keep minimal requirement in sync with NPY_TARGET_VERSION
-    # upper cap should be lifted when build-time requirement is bumped to >=2.0, see
-    # https://github.com/scipy/oldest-supported-numpy/issues/76#issuecomment-1628865694
-    "numpy>=1.17.5,<2.0",
+    "numpy>=1.19.3, <2.0", # keep minimal requirement in sync with NPY_TARGET_VERSION
     "packaging>=20.9",
-    "pillow>=6.2.1", # transitive dependency via MPL (>=3.3)
+    "pillow>=8.0.0",
     "tomli-w>=0.4.0",
     "tqdm>=3.4.0",
     "unyt>=2.9.2,<3.0", # see https://github.com/yt-project/yt/issues/4162
-    "importlib_resources>=1.3;python_version < '3.9'",
     "tomli>=1.2.3;python_version < '3.11'",
     "typing-extensions>=4.1.0;python_version < '3.11'",
 ]
@@ -140,7 +133,7 @@ ytdata = ["yt[HDF5]"]
 # "full" should contain all optional dependencies intended for users (not devs)
 # in particular it should enable support for all frontends
 full = [
-    "cartopy>=0.22.0; python_version >= '3.9'",
+    "cartopy>=0.22.0",
     "firefly>=3.2.0",
     "glueviz>=0.13.3",
     "ipython>=2.0.0",
@@ -219,13 +212,12 @@ minimal = [
     "ipywidgets==8.0.0",
     "matplotlib==3.5",
     "more-itertools==8.4",
-    "numpy==1.17.5",
+    "numpy==1.19.3",
     "packaging==20.9",
-    "pillow==6.2.1",
+    "pillow==8.0.0",
     "tomli-w==0.4.0",
     "tqdm==3.4.0",
     "unyt==2.9.2",
-    "importlib_resources==1.3;python_version < '3.9'",
     "tomli==1.2.3;python_version < '3.11'",
     "typing-extensions==4.1.0;python_version < '3.11'",
 ]
@@ -239,11 +231,10 @@ test = [
     "nose-timer~=1.0.0; python_version < '3.10'",
 ]
 typecheck = [
-    "mypy==1.0.0",
+    "mypy==1.5.1",
     "types-PyYAML==6.0.12.2",
     "types-chardet==5.0.4",
     "types-requests==2.28.11.5",
-    "importlib_resources==1.3;python_version < '3.9'",
     "typing-extensions==4.1.0;python_version < '3.11'",
 ]
 
@@ -260,7 +251,7 @@ namespaces = false
 
 [tool.black]
 line-length = 88
-target-version = ['py38']
+target-version = ['py39']
 include = '\.pyi?$'
 exclude = '''
 /(
@@ -488,7 +479,7 @@ ignore = [
 
 
 [tool.mypy]
-python_version = 3.8
+python_version = 3.9
 show_error_codes = true
 ignore_missing_imports = true
 warn_unused_configs = true

setup.py

@@ -2,6 +2,7 @@
 import os
 from collections import defaultdict
 from distutils.ccompiler import get_default_compiler
+from importlib import resources as importlib_resources
 
 from setuptools import Distribution, setup
 
@@ -10,7 +11,6 @@
     check_for_openmp,
     check_for_pyembree,
     create_build_ext,
-    get_ewah_bool_utils_path,
     install_ccompiler,
 )
 
@@ -49,7 +49,8 @@
         "yt/frontends/artio/artio_headers/",
     ],
     "STD_LIBS": std_libs,
-    "EWAH_LIBS": std_libs + [get_ewah_bool_utils_path()],
+    "EWAH_LIBS": std_libs
+    + [os.path.abspath(importlib_resources.files("ewah_bool_utils"))],
     "OMP_ARGS": omp_args,
     "FIXED_INTERP": "yt/utilities/lib/fixed_interpolator.cpp",
     "ARTIO_SOURCE": sorted(glob.glob("yt/frontends/artio/artio_headers/*.c")),

setupext.py

@@ -17,11 +17,7 @@
 from setuptools.command.build_ext import build_ext as _build_ext
 from setuptools.command.sdist import sdist as _sdist
 from setuptools.errors import CompileError, LinkError
-
-if sys.version_info >= (3, 9):
-    import importlib.resources as importlib_resources
-else:
-    import importlib_resources
+import importlib.resources as importlib_resources
 
 log = logging.getLogger("setupext")
 
@@ -204,12 +200,6 @@ def check_CPP14_flags(possible_compile_flags):
     )
     return []
 
-def get_ewah_bool_utils_path():
-    if sys.version_info >= (3, 9):
-        return os.path.abspath(importlib_resources.files("ewah_bool_utils"))
-    else:
-        from pkg_resources import resource_filename
-        return os.path.dirname(os.path.abspath(resource_filename("ewah_bool_utils", "ewah_bool_wrap.pxd")))
 
 def check_for_pyembree(std_libs):
     embree_libs = []
@@ -411,12 +401,9 @@ def finalize_options(self):
 
             define_macros = [
                 ("NPY_NO_DEPRECATED_API", "NPY_1_7_API_VERSION"),
-            ]
-            if sys.version_info >= (3, 9):
                 # keep in sync with runtime requirements (pyproject.toml)
-                define_macros.append(("NPY_TARGET_VERSION", "NPY_1_18_API_VERSION"))
-            else:
-                pass
+                ("NPY_TARGET_VERSION", "NPY_1_19_API_VERSION"),
+            ]
 
             if self.define is None:
                 self.define = define_macros

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.
         """