ci: Drop support for Python 3.8

.github/workflows/build.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.9", "3.10", "3.11", "3.12"]
         jsonschema-version: ["3.0", "latest"]
     name: py ${{ matrix.python-version }} js ${{ matrix.jsonschema-version }}
     steps:
@@ -28,18 +28,18 @@ jobs:
       - name: Maybe uninstall optional dependencies
         # We uninstall pyarrow and vegafusion for one job to test that we have not
         # accidentally introduced a hard dependency on these libraries.
-        # Uninstalling for Python 3.8 is an arbitrary choice.
+        # Uninstalling for Python 3.9 is an arbitrary choice.
         # Also see https://github.com/vega/altair/pull/3114
-        if: ${{ matrix.python-version == '3.8' }}
+        if: ${{ matrix.python-version == '3.9' }}
         run: |
           pip uninstall -y pyarrow vegafusion vegafusion-python-embed vl-convert-python anywidget
       - name: Maybe install lowest supported pandas version
         # We install the lowest supported pandas version for one job to test that
         # it still works. Downgrade to the oldest versions of pandas and numpy that include
-        # Python 3.8 wheels, so only run this job for Python 3.8
-        if: ${{ matrix.python-version == '3.8' }}
+        # Python 3.9 wheels, so only run this job for Python 3.9
+        if: ${{ matrix.python-version == '3.9' }}
         run: |
-          pip install pandas==0.25.3 numpy==1.17.5
+          pip install pandas==1.1.3 numpy==1.19.3
       - name: Test that schema generation has no effect
         run: |
           pip install vl-convert-python

altair/expr/core.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import Any, Dict, Union
+from typing import Any, Union
 from typing_extensions import TypeAlias
 
 from altair.utils import SchemaBase
@@ -237,4 +237,4 @@ def __repr__(self) -> str:
         return f"{self.group}[{self.name!r}]"
 
 
-IntoExpression: TypeAlias = Union[bool, None, str, float, OperatorMixin, Dict[str, Any]]
+IntoExpression: TypeAlias = Union[bool, None, str, float, OperatorMixin, dict[str, Any]]

altair/utils/_dfi_types.py

@@ -7,7 +7,10 @@
 from __future__ import annotations
 
 import enum
-from typing import Any, Iterable, Protocol
+from typing import TYPE_CHECKING, Any, Protocol
+
+if TYPE_CHECKING:
+    from collections.abc import Iterable
 
 
 class DtypeKind(enum.IntEnum):

altair/utils/_show.py

@@ -2,7 +2,10 @@
 
 import webbrowser
 from http.server import BaseHTTPRequestHandler, HTTPServer
-from typing import Iterable
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from collections.abc import Iterable
 
 
 def open_html_in_browser(

altair/utils/_transformed_data.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from typing import TYPE_CHECKING, Any, Dict, Iterable, Tuple, overload
+from typing import TYPE_CHECKING, Any, overload
 from typing_extensions import TypeAlias
 
 from altair import (
@@ -31,11 +31,13 @@
 from altair.utils.schemapi import Undefined
 
 if TYPE_CHECKING:
+    from collections.abc import Iterable
+
     from altair.typing import ChartType
     from altair.utils.core import DataFrameLike
 
-Scope: TypeAlias = Tuple[int, ...]
-FacetMapping: TypeAlias = Dict[Tuple[str, Scope], Tuple[str, Scope]]
+Scope: TypeAlias = tuple[int, ...]
+FacetMapping: TypeAlias = dict[tuple[str, Scope], tuple[str, Scope]]
 
 
 # For the transformed_data functionality, the chart classes in the values

altair/utils/_vegafusion_data.py

@@ -1,16 +1,7 @@
 from __future__ import annotations
 
 import uuid
-from typing import (
-    TYPE_CHECKING,
-    Any,
-    Callable,
-    Final,
-    MutableMapping,
-    TypedDict,
-    Union,
-    overload,
-)
+from typing import TYPE_CHECKING, Any, Callable, Final, TypedDict, Union, overload
 from weakref import WeakValueDictionary
 
 from altair.utils._importers import import_vegafusion
@@ -24,6 +15,8 @@
 from altair.vegalite.data import default_data_transformer
 
 if TYPE_CHECKING:
+    from collections.abc import MutableMapping
+
     from narwhals.typing import IntoDataFrame
 
     from vegafusion.runtime import ChartState

altair/utils/compiler.py

@@ -1,12 +1,12 @@
-from typing import Any, Callable, Dict
+from typing import Any, Callable
 
 from altair.utils import PluginRegistry
 
 # ==============================================================================
 # Vega-Lite to Vega compiler registry
 # ==============================================================================
-VegaLiteCompilerType = Callable[[Dict[str, Any]], Dict[str, Any]]
+VegaLiteCompilerType = Callable[[dict[str, Any]], dict[str, Any]]
 
 
-class VegaLiteCompilerRegistry(PluginRegistry[VegaLiteCompilerType, Dict[str, Any]]):
+class VegaLiteCompilerRegistry(PluginRegistry[VegaLiteCompilerType, dict[str, Any]]):
     pass

altair/utils/core.py

@@ -8,20 +8,11 @@
 import sys
 import traceback
 import warnings
-from collections.abc import Mapping, MutableMapping
+from collections.abc import Iterator, Mapping, MutableMapping
 from copy import deepcopy
 from itertools import groupby
 from operator import itemgetter
-from typing import (
-    TYPE_CHECKING,
-    Any,
-    Callable,
-    Iterator,
-    Literal,
-    TypeVar,
-    cast,
-    overload,
-)
+from typing import TYPE_CHECKING, Any, Callable, Literal, TypeVar, cast, overload
 
 import jsonschema
 import narwhals.stable.v1 as nw

altair/utils/data.py

@@ -4,18 +4,15 @@
 import json
 import random
 import sys
+from collections.abc import MutableMapping, Sequence
 from functools import partial
 from pathlib import Path
 from typing import (
     TYPE_CHECKING,
     Any,
     Callable,
-    Dict,
-    List,
     Literal,
-    MutableMapping,
     Protocol,
-    Sequence,
     TypedDict,
     TypeVar,
     Union,
@@ -54,17 +51,17 @@ class SupportsGeoInterface(Protocol):
 
 
 DataType: TypeAlias = Union[
-    Dict[Any, Any], IntoDataFrame, SupportsGeoInterface, DataFrameLike
+    dict[Any, Any], IntoDataFrame, SupportsGeoInterface, DataFrameLike
 ]
 
 TDataType = TypeVar("TDataType", bound=DataType)
 TIntoDataFrame = TypeVar("TIntoDataFrame", bound=IntoDataFrame)
 
-VegaLiteDataDict: TypeAlias = Dict[
-    str, Union[str, Dict[Any, Any], List[Dict[Any, Any]]]
+VegaLiteDataDict: TypeAlias = dict[
+    str, Union[str, dict[Any, Any], list[dict[Any, Any]]]
 ]
-ToValuesReturnType: TypeAlias = Dict[str, Union[Dict[Any, Any], List[Dict[Any, Any]]]]
-SampleReturnType = Union[IntoDataFrame, Dict[str, Sequence], None]
+ToValuesReturnType: TypeAlias = dict[str, Union[dict[Any, Any], list[dict[Any, Any]]]]
+SampleReturnType = Union[IntoDataFrame, dict[str, Sequence], None]
 
 
 def is_data_type(obj: Any) -> TypeIs[DataType]:

altair/utils/display.py

@@ -4,7 +4,7 @@
 import pkgutil
 import textwrap
 import uuid
-from typing import Any, Callable, Dict, Tuple, Union
+from typing import Any, Callable, Union
 from typing_extensions import TypeAlias
 
 from ._vegafusion_data import compile_with_vegafusion, using_vegafusion
@@ -18,16 +18,16 @@
 # MimeBundleType needs to be the same as what are acceptable return values
 # for _repr_mimebundle_,
 # see https://ipython.readthedocs.io/en/stable/config/integrating.html#MyObject._repr_mimebundle_
-MimeBundleDataType: TypeAlias = Dict[str, Any]
-MimeBundleMetaDataType: TypeAlias = Dict[str, Any]
+MimeBundleDataType: TypeAlias = dict[str, Any]
+MimeBundleMetaDataType: TypeAlias = dict[str, Any]
 MimeBundleType: TypeAlias = Union[
-    MimeBundleDataType, Tuple[MimeBundleDataType, MimeBundleMetaDataType]
+    MimeBundleDataType, tuple[MimeBundleDataType, MimeBundleMetaDataType]
 ]
 RendererType: TypeAlias = Callable[..., MimeBundleType]
 # Subtype of MimeBundleType as more specific in the values of the dictionaries
 
-DefaultRendererReturnType: TypeAlias = Tuple[
-    Dict[str, Union[str, Dict[str, Any]]], Dict[str, Dict[str, Any]]
+DefaultRendererReturnType: TypeAlias = tuple[
+    dict[str, Union[str, dict[str, Any]]], dict[str, dict[str, Any]]
 ]
 
 

altair/utils/schemapi.py

@@ -9,22 +9,17 @@
 import sys
 import textwrap
 from collections import defaultdict
+from collections.abc import Iterable, Iterator, Mapping, Sequence
 from functools import partial
 from importlib.metadata import version as importlib_version
 from itertools import chain, zip_longest
 from math import ceil
 from typing import (
     TYPE_CHECKING,
     Any,
-    Dict,
     Final,
     Generic,
-    Iterable,
-    Iterator,
-    List,
     Literal,
-    Mapping,
-    Sequence,
     TypeVar,
     Union,
     cast,
@@ -67,8 +62,8 @@
         from typing_extensions import Never, Self
     _OptionalModule: TypeAlias = "ModuleType | None"
 
-ValidationErrorList: TypeAlias = List[jsonschema.exceptions.ValidationError]
-GroupedValidationErrors: TypeAlias = Dict[str, ValidationErrorList]
+ValidationErrorList: TypeAlias = list[jsonschema.exceptions.ValidationError]
+GroupedValidationErrors: TypeAlias = dict[str, ValidationErrorList]
 
 # This URI is arbitrary and could be anything else. It just cannot be an empty
 # string as we need to reference the schema registered in
@@ -1351,7 +1346,7 @@ def _replace_parsed_shorthand(
 
 TSchemaBase = TypeVar("TSchemaBase", bound=SchemaBase)
 
-_CopyImpl = TypeVar("_CopyImpl", SchemaBase, Dict[Any, Any], List[Any])
+_CopyImpl = TypeVar("_CopyImpl", SchemaBase, dict[Any, Any], list[Any])
 """
 Types which have an implementation in ``SchemaBase.copy()``.
 

altair/utils/selection.py

@@ -1,11 +1,11 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from typing import Any, Dict, List, NewType
+from typing import Any, NewType
 
 # Type representing the "{selection}_store" dataset that corresponds to a
 # Vega-Lite selection
-Store = NewType("Store", List[Dict[str, Any]])
+Store = NewType("Store", list[dict[str, Any]])
 
 
 @dataclass(frozen=True, eq=True)

altair/vegalite/v5/api.py

@@ -10,7 +10,7 @@
 import typing as t
 import warnings
 from copy import deepcopy as _deepcopy
-from typing import TYPE_CHECKING, Any, Literal, Sequence, TypeVar, Union, overload
+from typing import TYPE_CHECKING, Any, Literal, TypeVar, Union, overload
 
 import jsonschema
 import narwhals.stable.v1 as nw
@@ -47,8 +47,9 @@
     from typing_extensions import TypeAlias
 
 if TYPE_CHECKING:
+    from collections.abc import Iterable, Iterator, Sequence
     from pathlib import Path
-    from typing import IO, Iterable, Iterator
+    from typing import IO
 
     from altair.utils.core import DataFrameLike
 
@@ -661,7 +662,7 @@ class _ConditionClosed(TypedDict, closed=True, total=False):  # type: ignore[cal
     value: Any
 
 
-_Conditions: TypeAlias = t.List[_ConditionClosed]
+_Conditions: TypeAlias = list[_ConditionClosed]
 """
 Chainable conditions produced by ``.when()`` and ``Then.when()``.
 

altair/vegalite/v5/schema/_config.py

@@ -4,7 +4,7 @@
 from __future__ import annotations
 
 import sys
-from typing import TYPE_CHECKING, Any, Literal, Sequence, TypedDict
+from typing import TYPE_CHECKING, Any, Literal, TypedDict
 
 if sys.version_info >= (3, 14):
     from typing import TypedDict
@@ -14,6 +14,8 @@
 
 if TYPE_CHECKING:
     # ruff: noqa: F405
+    from collections.abc import Sequence
+
     from ._typing import *  # noqa: F403
 
 

altair/vegalite/v5/schema/_typing.py

@@ -5,7 +5,8 @@
 
 import re
 import sys
-from typing import Any, Generic, Literal, Mapping, Sequence, TypeVar, Union
+from collections.abc import Mapping, Sequence
+from typing import Annotated, Any, Generic, Literal, TypeVar, Union, get_args
 
 if sys.version_info >= (3, 14):  # https://peps.python.org/pep-0728/
     from typing import TypedDict
@@ -32,11 +33,6 @@
 else:
     from typing_extensions import TypeAlias
 
-if sys.version_info >= (3, 9):
-    from typing import Annotated, get_args
-else:
-    from typing_extensions import Annotated, get_args
-
 
 __all__ = [
     "AggregateOp_T",

altair/vegalite/v5/schema/channels.py

@@ -11,7 +11,7 @@
 # However, we need these overloads due to how the propertysetter works
 # mypy: disable-error-code="no-overload-impl, empty-body, misc"
 import sys
-from typing import TYPE_CHECKING, Any, Literal, Sequence, TypedDict, Union, overload
+from typing import TYPE_CHECKING, Any, Literal, TypedDict, Union, overload
 
 if sys.version_info >= (3, 10):
     from typing import TypeAlias
@@ -28,6 +28,8 @@
 
 if TYPE_CHECKING:
     # ruff: noqa: F405
+    from collections.abc import Sequence
+
     from altair import Parameter, SchemaBase
     from altair.typing import Optional
     from altair.vegalite.v5.api import IntoCondition

altair/vegalite/v5/schema/core.py

@@ -5,7 +5,7 @@
 
 import json
 import pkgutil
-from typing import TYPE_CHECKING, Any, Iterator, Literal, Sequence
+from typing import TYPE_CHECKING, Any, Literal
 
 from altair.utils.schemapi import (  # noqa: F401
     SchemaBase,
@@ -16,6 +16,8 @@
 
 if TYPE_CHECKING:
     # ruff: noqa: F405
+    from collections.abc import Iterator, Sequence
+
     from altair import Parameter
     from altair.typing import Optional