Introduce _typing module for version-dependent typing imports (#1088)

* Introduce _typing module for version-dependent typing imports

* Remove unused import

src/textual/__init__.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import inspect
-import sys
 from typing import Callable
 
 import rich.repr
@@ -12,11 +11,7 @@ __all__ = ["log", "panic"]
 
 from ._context import active_app
 from ._log import LogGroup, LogVerbosity
-
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
+from ._typing import TypeAlias
 
 
 LogCallable: TypeAlias = "Callable"

src/textual/_border.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import sys
 from functools import lru_cache
 from typing import cast, Tuple, Union
 
@@ -11,11 +10,7 @@ from rich.style import Style
 
 from .color import Color
 from .css.types import EdgeStyle, EdgeType
-
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
+from ._typing import TypeAlias
 
 INNER = 1
 OUTER = 2

src/textual/_compositor.py

@@ -13,10 +13,9 @@ without having to render the entire screen.
 
 from __future__ import annotations
 
-import sys
 from itertools import chain
 from operator import itemgetter
-from typing import TYPE_CHECKING, Callable, Iterable, NamedTuple, cast
+from typing import TYPE_CHECKING, Iterable, NamedTuple, cast
 
 import rich.repr
 from rich.console import Console, ConsoleOptions, RenderableType, RenderResult
@@ -27,15 +26,9 @@ from rich.style import Style
 from . import errors
 from ._cells import cell_len
 from ._loop import loop_last
-from ._profile import timer
 from ._types import Lines
 from .geometry import Offset, Region, Size
-
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
-
+from ._typing import TypeAlias
 
 if TYPE_CHECKING:
     from .widget import Widget

src/textual/_layout.py

@@ -1,22 +1,14 @@
 from __future__ import annotations
 
 from abc import ABC, abstractmethod
-import sys
 from typing import ClassVar, NamedTuple, TYPE_CHECKING
 
-
 from .geometry import Region, Size, Spacing
-
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
-
+from ._typing import TypeAlias
 
 if TYPE_CHECKING:
     from .widget import Widget
 
-
 ArrangeResult: TypeAlias = "tuple[list[WidgetPlacement], set[Widget]]"
 DockArrangeResult: TypeAlias = "tuple[list[WidgetPlacement], set[Widget], Spacing]"
 

src/textual/_styles_cache.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import sys
 from typing import TYPE_CHECKING, Callable, Iterable, List
 
 from rich.segment import Segment
@@ -11,22 +10,16 @@ from ._filter import LineFilter
 from ._opacity import _apply_opacity
 from ._segment_tools import line_crop, line_pad, line_trim
 from ._types import Lines
+from ._typing import TypeAlias
 from .color import Color
 from .geometry import Region, Size, Spacing
 from .renderables.text_opacity import TextOpacity
 from .renderables.tint import Tint
 
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
-
-
 if TYPE_CHECKING:
     from .css.styles import StylesBase
     from .widget import Widget
 
-
 RenderLineCallback: TypeAlias = Callable[[int], List[Segment]]
 
 

src/textual/_types.py

@@ -1,13 +1,8 @@
-import sys
 from typing import Awaitable, Callable, List, TYPE_CHECKING, Union
 
 from rich.segment import Segment
 
-if sys.version_info >= (3, 8):
-    from typing import Protocol
-else:
-    from typing_extensions import Protocol
-
+from textual._typing import Protocol
 
 if TYPE_CHECKING:
     from .message import Message

src/textual/_typing.py

@@ -0,0 +1,11 @@
+import sys
+
+if sys.version_info >= (3, 10):
+    from typing import TypeAlias
+else:  # pragma: no cover
+    from typing_extensions import TypeAlias
+
+if sys.version_info >= (3, 8):
+    from typing import Final, Literal, Protocol, TypedDict
+else:
+    from typing_extensions import Final, Literal, Protocol, TypedDict

src/textual/app.py

@@ -1,8 +1,6 @@
 from __future__ import annotations
 
 import asyncio
-from asyncio import Task
-from contextlib import asynccontextmanager
 import inspect
 import io
 import os
@@ -10,14 +8,14 @@ import platform
 import sys
 import unicodedata
 import warnings
+from asyncio import Task
+from contextlib import asynccontextmanager
 from contextlib import redirect_stderr, redirect_stdout
 from datetime import datetime
 from pathlib import Path, PurePath
 from time import perf_counter
 from typing import (
     Any,
-    Callable,
-    Coroutine,
     Generic,
     Iterable,
     Type,
@@ -29,9 +27,6 @@ from typing import (
 )
 from weakref import WeakSet, WeakValueDictionary
 
-from ._ansi_sequences import SYNC_END, SYNC_START
-from ._path import _make_path_object_relative
-
 import nanoid
 import rich
 import rich.repr
@@ -42,10 +37,13 @@ from rich.traceback import Traceback
 
 from . import Logger, LogGroup, LogVerbosity, actions, events, log, messages
 from ._animator import Animator, DEFAULT_EASING, Animatable, EasingFunction
+from ._ansi_sequences import SYNC_END, SYNC_START
 from ._callback import invoke
 from ._context import active_app
 from ._event_broker import NoHandler, extract_handler_actions
 from ._filter import LineFilter, Monochrome
+from ._path import _make_path_object_relative
+from ._typing import TypeAlias
 from .binding import Binding, Bindings
 from .css.query import NoMatches
 from .css.stylesheet import Stylesheet
@@ -67,11 +65,6 @@ if TYPE_CHECKING:
     from .devtools.client import DevtoolsClient
     from .pilot import Pilot
 
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
-
 PLATFORM = platform.system()
 WINDOWS = PLATFORM == "Windows"
 

src/textual/binding.py

@@ -1,15 +1,11 @@
 from __future__ import annotations
 
-import sys
 from dataclasses import dataclass
 from typing import Iterable, MutableMapping
 
 import rich.repr
 
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
+from textual._typing import TypeAlias
 
 BindingType: TypeAlias = "Binding | tuple[str, str, str]"
 

src/textual/css/_help_text.py

@@ -1,9 +1,9 @@
 from __future__ import annotations
 
-import sys
 from dataclasses import dataclass
-from typing import Iterable
+from typing import Iterable, Sequence
 
+from textual._typing import Literal
 from textual.color import ColorParseError
 from textual.css._help_renderables import Example, Bullet, HelpText
 from textual.css.constants import (
@@ -15,11 +15,6 @@ from textual.css.constants import (
     VALID_TEXT_ALIGN,
 )
 
-if sys.version_info >= (3, 8):
-    from typing import Literal, Iterable, Sequence
-else:
-    from typing_extensions import Literal
-
 from textual.css._error_tools import friendly_list
 from textual.css.scalar import SYMBOL_UNIT
 

src/textual/css/constants.py

@@ -1,13 +1,8 @@
 from __future__ import annotations
-import sys
 import typing
 
-if sys.version_info >= (3, 8):
-    from typing import Final
-else:
-    from typing_extensions import Final  # pragma: no cover
-
 from ..geometry import Spacing
+from .._typing import Final
 
 if typing.TYPE_CHECKING:
     from .types import EdgeType

src/textual/css/styles.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import sys
 from abc import ABC, abstractmethod
 from dataclasses import dataclass, field
 from functools import lru_cache
@@ -60,11 +59,7 @@ from .types import (
     Visibility,
     TextAlign,
 )
-
-if sys.version_info >= (3, 8):
-    from typing import TypedDict
-else:
-    from typing_extensions import TypedDict
+from .._typing import TypedDict
 
 if TYPE_CHECKING:
     from .._layout import Layout

src/textual/css/types.py

@@ -1,15 +1,9 @@
 from __future__ import annotations
 
-import sys
 from typing import Tuple
 
 from ..color import Color
-
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal
-
+from .._typing import Literal
 
 Edge = Literal["top", "right", "bottom", "left"]
 DockEdge = Literal["top", "right", "bottom", "left", ""]

src/textual/devtools/renderables.py

@@ -1,17 +1,11 @@
 from __future__ import annotations
 
-import sys
 from datetime import datetime
 from pathlib import Path
 from typing import Iterable
 
 from importlib_metadata import version
 
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal
-
 from rich.align import Align
 from rich.console import Console, ConsoleOptions, RenderResult
 from rich.markup import escape
@@ -22,6 +16,7 @@ from rich.styled import Styled
 from rich.table import Table
 from rich.text import Text
 from textual._log import LogGroup
+from textual._typing import Literal
 
 DevConsoleMessageLevel = Literal["info", "warning", "error"]
 

src/textual/dom.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import re
-import sys
 from collections import deque
 from inspect import getfile
 from typing import (
@@ -42,20 +41,10 @@ if TYPE_CHECKING:
     from .screen import Screen
     from .widget import Widget
 
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal
-
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
-
+from textual._typing import Literal, TypeAlias
 
 _re_identifier = re.compile(IDENTIFIER)
 
-
 WalkMethod: TypeAlias = Literal["depth", "breadth"]
 
 

src/textual/features.py

@@ -1,13 +1,7 @@
 from __future__ import annotations
 
-import sys
-
 from typing import cast
-
-if sys.version_info >= (3, 8):
-    from typing import Final, Literal
-else:
-    from typing_extensions import Final, Literal
+from textual._typing import Final, Literal
 
 FEATURES: Final = {"devtools", "debug", "headless"}
 

src/textual/geometry.py

@@ -6,15 +6,11 @@ Functions and classes to manage terminal geometry (anything involving coordinate
 
 from __future__ import annotations
 
-import sys
 from functools import lru_cache
 from operator import attrgetter, itemgetter
 from typing import Any, Collection, NamedTuple, Tuple, TypeVar, Union, cast
 
-if sys.version_info >= (3, 10):
-    from typing import TypeAlias
-else:  # pragma: no cover
-    from typing_extensions import TypeAlias
+from textual._typing import TypeAlias
 
 SpacingDimensions: TypeAlias = Union[
     int, Tuple[int], Tuple[int, int], Tuple[int, int, int, int]

src/textual/screen.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import sys
 from typing import Iterable, Iterator
 
 import rich.repr
@@ -13,14 +12,11 @@ from ._compositor import Compositor, MapGeometry
 from .timer import Timer
 from ._types import CallbackType
 from .geometry import Offset, Region, Size
+from ._typing import Final
 from .reactive import Reactive
 from .renderables.blank import Blank
 from .widget import Widget
 
-if sys.version_info >= (3, 8):
-    from typing import Final
-else:
-    from typing_extensions import Final
 
 # Screen updates will be batched so that they don't happen more often than 60 times per second:
 UPDATE_PERIOD: Final = 1 / 60

src/textual/widget.py

@@ -5,7 +5,6 @@ from fractions import Fraction
 from itertools import islice
 from operator import attrgetter
 from typing import (
-    Awaitable,
     Generator,
     TYPE_CHECKING,
     ClassVar,

src/textual/widgets/_button.py

@@ -1,14 +1,8 @@
 from __future__ import annotations
 
-import sys
 from functools import partial
 from typing import cast
 
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal  # pragma: no cover
-
 import rich.repr
 from rich.console import RenderableType
 from rich.text import Text, TextType
@@ -18,6 +12,7 @@ from ..css._error_tools import friendly_list
 from ..message import Message
 from ..reactive import Reactive
 from ..widgets import Static
+from .._typing import Literal
 
 ButtonVariant = Literal["default", "primary", "success", "warning", "error"]
 _VALID_BUTTON_VARIANTS = {"default", "primary", "success", "warning", "error"}

src/textual/widgets/_data_table.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import sys
 from dataclasses import dataclass, field
 from itertools import chain, zip_longest
 from typing import ClassVar, Generic, Iterable, NamedTuple, TypeVar, cast
@@ -14,18 +13,13 @@ from rich.text import Text, TextType
 
 from .. import events, messages
 from .._cache import LRUCache
-from .._profile import timer
 from .._segment_tools import line_crop
 from .._types import Lines
 from ..geometry import Region, Size, Spacing, clamp
 from ..reactive import Reactive
 from ..render import measure
 from ..scroll_view import ScrollView
-
-if sys.version_info >= (3, 8):
-    from typing import Literal
-else:
-    from typing_extensions import Literal
+from .._typing import Literal
 
 CursorType = Literal["cell", "row", "column"]
 CELL: CursorType = "cell"
@@ -115,16 +109,15 @@ class Coord(NamedTuple):
 
 
 class DataTable(ScrollView, Generic[CellType], can_focus=True):
-
     DEFAULT_CSS = """
     App.-dark DataTable {
         background:;
     }
     DataTable {
         background: $surface ;
-        color: $text;           
+        color: $text;
     }
-    DataTable > .datatable--header {        
+    DataTable > .datatable--header {
         text-style: bold;
         background: $primary;
         color: $text;
@@ -136,7 +129,7 @@ class DataTable(ScrollView, Generic[CellType], can_focus=True):
     }
 
     DataTable > .datatable--odd-row {
-        
+
     }
 
     DataTable > .datatable--even-row {

tests/css/test_styles.py

@@ -1,16 +1,9 @@
-import sys
 from decimal import Decimal
 
-if sys.version_info >= (3, 10):
-    from typing import Literal
-else:  # pragma: no cover
-    from typing_extensions import Literal
-
 import pytest
 
 from rich.style import Style
 
-from textual.app import ComposeResult
 from textual.color import Color
 from textual.css.errors import StyleValueError
 from textual.css.scalar import Scalar, Unit