diff options
| -rw-r--r-- | discord/ext/commands/core.py | 25 | ||||
| -rw-r--r-- | discord/ext/commands/errors.py | 35 |
2 files changed, 55 insertions, 5 deletions
diff --git a/discord/ext/commands/core.py b/discord/ext/commands/core.py index df82efe2..9bb102b5 100644 --- a/discord/ext/commands/core.py +++ b/discord/ext/commands/core.py @@ -28,6 +28,7 @@ import asyncio import inspect import discord import functools +import typing from .errors import * from .cooldowns import Cooldown, BucketType, CooldownMapping @@ -212,10 +213,7 @@ class Command: self.instance = instance return self - async def do_conversion(self, ctx, converter, argument, param): - if converter is bool: - return _convert_to_bool(argument) - + async def _actual_conversion(self, ctx, converter, argument, param): try: module = converter.__module__ except: @@ -255,6 +253,25 @@ class Command: raise BadArgument('Converting to "{}" failed for parameter "{}".'.format(name, param.name)) from e + async def do_conversion(self, ctx, converter, argument, param): + if converter is bool: + return _convert_to_bool(argument) + + if type(converter) is typing._Union: + errors = [] + for conv in converter.__args__: + try: + value = await self._actual_conversion(ctx, conv, argument, param) + except CommandError as e: + errors.append(e) + else: + return value + + # if we're here, then we failed all the converters + raise BadUnionArgument(param, converter.__args__, errors) + + return await self._actual_conversion(ctx, converter, argument, param) + def _get_converter(self, param): converter = param.annotation if converter is param.empty: diff --git a/discord/ext/commands/errors.py b/discord/ext/commands/errors.py index 4b3c2293..f3d20ba5 100644 --- a/discord/ext/commands/errors.py +++ b/discord/ext/commands/errors.py @@ -30,7 +30,8 @@ __all__ = [ 'CommandError', 'MissingRequiredArgument', 'BadArgument', 'NoPrivateMessage', 'CheckFailure', 'CommandNotFound', 'DisabledCommand', 'CommandInvokeError', 'TooManyArguments', 'UserInputError', 'CommandOnCooldown', 'NotOwner', - 'MissingPermissions', 'BotMissingPermissions', 'ConversionError'] + 'MissingPermissions', 'BotMissingPermissions', 'ConversionError', + 'BadUnionArgument'] class CommandError(DiscordException): """The base exception type for all command related errors. @@ -191,3 +192,35 @@ class BotMissingPermissions(CheckFailure): fmt = ' and '.join(missing) message = 'Bot requires {} permission(s) to run command.'.format(fmt) super().__init__(message, *args) + +class BadUnionArgument(UserInputError): + """Exception raised when a :class:`typing.Union` converter fails for all + its associated types. + + Attributes + ----------- + param: :class:`inspect.Parameter` + The parameter that failed being converted. + converters: Tuple[Type, ...] + A tuple of converters attempted in conversion, in order of failure. + errors: List[:class:`CommandError`] + A list of errors that were caught from failing the conversion. + """ + def __init__(self, param, converters, errors): + self.param = param + self.converters = converters + self.errors = errors + + def _get_name(x): + try: + return x.__name__ + except AttributeError: + return x.__class__.__name__ + + to_string = [_get_name(x) for x in converters] + if len(to_string) > 2: + fmt = '{}, or {}'.format(', '.join(to_string[:-1]), to_string[-1]) + else: + fmt = ' or '.join(to_string) + + super().__init__('Could not convert "{0.name}" into {1}.'.format(param, fmt)) |