EmoteManager/utils/misc.py

# © 2018–2020 io mintz <io@mintz.cc>
#
# Emote Manager is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# Emote Manager is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with Emote Manager. If not, see <https://www.gnu.org/licenses/>.

"""various utilities for use within the bot"""

import asyncio

import discord

def format_user(bot, id, *, mention=False):
	"""Format a user ID for human readable display."""
	user = bot.get_user(id)
	if user is None:
		return f'Unknown user with ID {id}'
	# not mention: @null byte#8191 (140516693242937345)
	# mention: <@140516693242937345> (null byte#8191)
	# this allows people to still see the username and discrim
	# if they don't share a server with that user
	if mention:
		return f'{user.mention} (@{user})'
	else:
		return f'@{user} ({user.id})'

def format_http_exception(exception: discord.HTTPException):
	"""Formats a discord.HTTPException for relaying to the user.
	Sample return value:

	BAD REQUEST (status code: 400):
	Invalid Form Body
	In image: File cannot be larger than 256 kb.
	"""
	return (
		f'{exception.response.reason} (status code: {exception.response.status}):'
		f'\n{exception.text}')

def strip_angle_brackets(string):
	"""Strip leading < and trailing > from a string.
	Useful if a user sends you a url like <this> to avoid embeds, or to convert emotes to reactions."""
	if string.startswith('<') and string.endswith('>'):
		return string[1:-1]
	return string

async def gather_or_cancel(*awaitables, loop=None):
	"""run the awaitables in the sequence concurrently. If any of them raise an exception,
	propagate the first exception raised and cancel all other awaitables.
	"""
	gather_task = asyncio.gather(*awaitables, loop=loop)
	try:
		return await gather_task
	except asyncio.CancelledError:
		raise
	except:
		gather_task.cancel()
		raise