feat: add hints for animate function

src/textual/_animator.py

@@ -11,7 +11,7 @@
 from textual import _time
 from textual._callback import invoke
 from textual._compat import cached_property
-from textual._easing import DEFAULT_EASING, EASING
+from textual._easing import DEFAULT_EASING, EASING, DefaultEasingFunctions
 from textual._types import AnimationLevel, CallbackType
 from textual.timer import Timer
 
@@ -303,7 +303,7 @@ def animate(
         final_value: object = ...,
         duration: float | None = None,
         speed: float | None = None,
-        easing: EasingFunction | str = DEFAULT_EASING,
+        easing: EasingFunction | DefaultEasingFunctions = DEFAULT_EASING,
         delay: float = 0.0,
         on_complete: CallbackType | None = None,
         level: AnimationLevel = "full",

src/textual/_easing.py

@@ -4,6 +4,7 @@
 """
 
 from math import cos, pi, sin, sqrt
+from typing import Literal
 
 
 def _in_out_expo(x: float) -> float:
@@ -129,3 +130,39 @@ def _in_out_bounce(x: float) -> float:
 
 DEFAULT_EASING = "in_out_cubic"
 DEFAULT_SCROLL_EASING = "out_cubic"
+
+DefaultEasingFunctions = Literal[
+    "none",
+    "round",
+    "linear",
+    "in_sine",
+    "in_out_sine",
+    "out_sine",
+    "in_quad",
+    "in_out_quad",
+    "out_quad",
+    "in_cubic",
+    "in_out_cubic",
+    "out_cubic",
+    "in_quart",
+    "in_out_quart",
+    "out_quart",
+    "in_quint",
+    "in_out_quint",
+    "out_quint",
+    "in_expo",
+    "in_out_expo",
+    "out_expo",
+    "in_circ",
+    "in_out_circ",
+    "out_circ",
+    "in_back",
+    "in_out_back",
+    "out_back",
+    "in_elastic",
+    "in_out_elastic",
+    "out_elastic",
+    "in_bounce",
+    "in_out_bounce",
+    "out_bounce",
+]

src/textual/app.py

@@ -80,6 +80,7 @@
 from textual._context import active_app, active_message_pump
 from textual._context import message_hook as message_hook_context_var
 from textual._dispatch_key import dispatch_key
+from textual._easing import DefaultEasingFunctions
 from textual._event_broker import NoHandler, extract_handler_actions
 from textual._files import generate_datetime_filename
 from textual._path import (
@@ -1064,7 +1065,7 @@ def animate(
         duration: float | None = None,
         speed: float | None = None,
         delay: float = 0.0,
-        easing: EasingFunction | str = DEFAULT_EASING,
+        easing: EasingFunction | DefaultEasingFunctions = DEFAULT_EASING,
         on_complete: CallbackType | None = None,
         level: AnimationLevel = "full",
     ) -> None:

src/textual/css/styles.py

@@ -10,6 +10,7 @@
 from typing_extensions import TypedDict
 
 from textual._animator import DEFAULT_EASING, Animatable, BoundAnimator, EasingFunction
+from textual._easing import DefaultEasingFunctions
 from textual._types import AnimationLevel, CallbackType
 from textual.color import Color
 from textual.css._style_properties import (
@@ -1382,7 +1383,7 @@ def animate(
         duration: float | None = None,
         speed: float | None = None,
         delay: float = 0.0,
-        easing: EasingFunction | str = DEFAULT_EASING,
+        easing: EasingFunction | DefaultEasingFunctions = DEFAULT_EASING,
         on_complete: CallbackType | None = None,
         level: AnimationLevel = "full",
     ) -> None:

src/textual/widget.py

@@ -53,7 +53,7 @@
 from textual._context import NoActiveAppError
 from textual._debug import get_caller_file_and_line
 from textual._dispatch_key import dispatch_key
-from textual._easing import DEFAULT_SCROLL_EASING
+from textual._easing import DEFAULT_SCROLL_EASING, DefaultEasingFunctions
 from textual._extrema import Extrema
 from textual._styles_cache import StylesCache
 from textual._types import AnimationLevel
@@ -2463,7 +2463,7 @@ def animate(
         duration: float | None = None,
         speed: float | None = None,
         delay: float = 0.0,
-        easing: EasingFunction | str = DEFAULT_EASING,
+        easing: EasingFunction | DefaultEasingFunctions = DEFAULT_EASING,
         on_complete: CallbackType | None = None,
         level: AnimationLevel = "full",
     ) -> None: