feat: ✨ Allow for functools.partial and functions returning an awaitable as autocomplete (#2914)

* ✨ Allow for `functools.partials` and such as autocomplete

* 📝 CHANGELOG.md

* 🏷️ Better typing

* 🚚 Add partial autocomplete example

* 🩹 Make CI pass

* 📝 Move docstring to getter

* 🏷️ Boring typing stuff

* ✏️ Fix writing

* chore: 👽 Update base max filesize to `10` Mb (#2671)

* 👽 Update base max filesize to `10` Mb

* 📝 CHANGELOG.md

* 📝 Requested changes

* 📝 Grammar

* ♻️ Merge the 2 examples

* ⚰️ remove conflicting autocomplete attribute from `Option`

* 🐛 Fix missing setting autocomplete

* Copilot

Signed-off-by: Paillat <[email protected]>

* 📝 CHANGELOG.md

Signed-off-by: Paillat <[email protected]>

* Update CHANGELOG.md

Signed-off-by: Paillat <[email protected]>

* 📝 Update CHANGELOG.md

* 🐛 Missing description kwarg in autocomplete example

---------

Signed-off-by: Paillat <[email protected]>
Signed-off-by: Paillat <[email protected]>
Signed-off-by: Paillat <[email protected]>
Signed-off-by: Lala Sabathil <[email protected]>
Co-authored-by: Lala Sabathil <[email protected]>

Author: Paillat-dev

CHANGELOG.md

@@ -30,6 +30,9 @@ These changes are available on the `master` branch, but have not yet been releas
   - Adds pre-typed and pre-constructed with select_type `ui.Select` aliases for the
     different select types: `ui.StringSelect`, `ui.UserSelect`, `ui.RoleSelect`,
     `ui.MentionableSelect`, and `ui.ChannelSelect`.
+- Added the ability to use functions with any number of optional arguments and functions
+  returning an awaitable as `Option.autocomplete`.
+  ([#2914](https://github.com/Pycord-Development/pycord/pull/2914))
 - Added `ui.FileUpload` for modals and the `FileUpload` component.
   ([#2938](https://github.com/Pycord-Development/pycord/pull/2938))
 - Added support for Guild Incidents via `Guild.incidents_data` and

discord/commands/core.py

@@ -1119,7 +1119,7 @@ async def invoke_autocomplete_callback(self, ctx: AutocompleteContext):
                 ctx.value = op.get("value")
                 ctx.options = values
 
-                if len(inspect.signature(option.autocomplete).parameters) == 2:
+                if option.autocomplete._is_instance_method:
                     instance = getattr(option.autocomplete, "__self__", ctx.cog)
                     result = option.autocomplete(instance, ctx)
                 else:

discord/commands/options.py

@@ -28,12 +28,15 @@
 import logging
 import sys
 import types
+from collections.abc import Awaitable, Callable, Iterable
 from enum import Enum
 from typing import (
     TYPE_CHECKING,
+    Any,
     Literal,
     Optional,
     Type,
+    TypeVar,
     Union,
     get_args,
 )
@@ -54,13 +57,14 @@
     Thread,
     VoiceChannel,
 )
-from ..commands import ApplicationContext
+from ..commands import ApplicationContext, AutocompleteContext
 from ..enums import ChannelType
 from ..enums import Enum as DiscordEnum
 from ..enums import SlashCommandOptionType
 from ..utils import MISSING, basic_autocomplete
 
 if TYPE_CHECKING:
+    from ..cog import Cog
     from ..ext.commands import Converter
     from ..member import Member
     from ..message import Attachment
@@ -86,6 +90,25 @@
         Type[DiscordEnum],
     ]
 
+    AutocompleteReturnType = Union[
+        Iterable["OptionChoice"], Iterable[str], Iterable[int], Iterable[float]
+    ]
+    T = TypeVar("T", bound=AutocompleteReturnType)
+    MaybeAwaitable = Union[T, Awaitable[T]]
+    AutocompleteFunction = Union[
+        Callable[[AutocompleteContext], MaybeAwaitable[AutocompleteReturnType]],
+        Callable[[Cog, AutocompleteContext], MaybeAwaitable[AutocompleteReturnType]],
+        Callable[
+            [AutocompleteContext, Any],  # pyright: ignore [reportExplicitAny]
+            MaybeAwaitable[AutocompleteReturnType],
+        ],
+        Callable[
+            [Cog, AutocompleteContext, Any],  # pyright: ignore [reportExplicitAny]
+            MaybeAwaitable[AutocompleteReturnType],
+        ],
+    ]
+
+
 __all__ = (
     "ThreadOption",
     "Option",
@@ -162,15 +185,6 @@ class Option:
     max_length: Optional[:class:`int`]
         The maximum length of the string that can be entered. Must be between 1 and 6000 (inclusive).
         Only applies to Options with an :attr:`input_type` of :class:`str`.
-    autocomplete: Optional[Callable[[:class:`.AutocompleteContext`], Awaitable[Union[Iterable[:class:`.OptionChoice`], Iterable[:class:`str`], Iterable[:class:`int`], Iterable[:class:`float`]]]]]
-        The autocomplete handler for the option. Accepts a callable (sync or async)
-        that takes a single argument of :class:`AutocompleteContext`.
-        The callable must return an iterable of :class:`str` or :class:`OptionChoice`.
-        Alternatively, :func:`discord.utils.basic_autocomplete` may be used in place of the callable.
-
-        .. note::
-
-            Does not validate the input value against the autocomplete results.
     channel_types: list[:class:`discord.ChannelType`] | None
         A list of channel types that can be selected in this option.
         Only applies to Options with an :attr:`input_type` of :class:`discord.SlashCommandOptionType.channel`.
@@ -292,6 +306,7 @@ def __init__(
         )
         self.default = kwargs.pop("default", None)
 
+        self._autocomplete: AutocompleteFunction | None = None
         self.autocomplete = kwargs.pop("autocomplete", None)
         if len(enum_choices) > 25:
             self.choices: list[OptionChoice] = []
@@ -443,6 +458,43 @@ def to_dict(self) -> dict:
     def __repr__(self):
         return f"<discord.commands.{self.__class__.__name__} name={self.name}>"
 
+    @property
+    def autocomplete(self) -> AutocompleteFunction | None:
+        """
+        The autocomplete handler for the option. Accepts a callable (sync or async)
+        that takes a single required argument of :class:`AutocompleteContext` or two arguments
+        of :class:`discord.Cog` (being the command's cog) and :class:`AutocompleteContext`.
+        The callable must return an iterable of :class:`str` or :class:`OptionChoice`.
+        Alternatively, :func:`discord.utils.basic_autocomplete` may be used in place of the callable.
+
+        Returns
+        -------
+        Optional[AutocompleteFunction]
+
+        .. versionchanged:: 2.7
+
+        .. note::
+            Does not validate the input value against the autocomplete results.
+        """
+        return self._autocomplete
+
+    @autocomplete.setter
+    def autocomplete(self, value: AutocompleteFunction | None) -> None:
+        self._autocomplete = value
+        # this is done here so it does not have to be computed every time the autocomplete is invoked
+        if self._autocomplete is not None:
+            self._autocomplete._is_instance_method = (  # pyright: ignore [reportFunctionMemberAccess]
+                sum(
+                    1
+                    for param in inspect.signature(
+                        self._autocomplete
+                    ).parameters.values()
+                    if param.default == param.empty  # pyright: ignore[reportAny]
+                    and param.kind not in (param.VAR_POSITIONAL, param.VAR_KEYWORD)
+                )
+                == 2
+            )
+
 
 class OptionChoice:
     """

examples/app_commands/slash_autocomplete.py

@@ -1,3 +1,5 @@
+from functools import partial
+
 import discord
 from discord.commands import option
 
@@ -196,4 +198,39 @@ async def autocomplete_basic_example(
     await ctx.respond(f"You picked {color} as your color, and {animal} as your animal!")
 
 
+FRUITS = ["Apple", "Banana", "Orange"]
+VEGETABLES = ["Carrot", "Lettuce", "Potato"]
+
+
+async def food_autocomplete(
+    ctx: discord.AutocompleteContext, food_type: str
+) -> list[discord.OptionChoice]:
+    items = FRUITS if food_type == "fruit" else VEGETABLES
+    return [
+        discord.OptionChoice(name=item)
+        for item in items
+        if ctx.value.lower() in item.lower()
+    ]
+
+
+@bot.slash_command(name="fruit")
+@option(
+    "choice",
+    description="Pick a fruit",
+    autocomplete=partial(food_autocomplete, food_type="fruit"),
+)
+async def get_fruit(ctx: discord.ApplicationContext, choice: str):
+    await ctx.respond(f'You picked "{choice}"')
+
+
+@bot.slash_command(name="vegetable")
+@option(
+    "choice",
+    description="Pick a vegetable",
+    autocomplete=partial(food_autocomplete, food_type="vegetable"),
+)
+async def get_vegetable(ctx: discord.ApplicationContext, choice: str):
+    await ctx.respond(f'You picked "{choice}"')
+
+
 bot.run("TOKEN")