Merge branch 'master' into bug/backend/b754/scheduler-suppresses-errors

34 files changed, 936 insertions, 353 deletions

diff --git a/bot/__main__.py b/bot/__main__.py
index 490163739..3df477a6d 100644
--- a/bot/__main__.py
+++ b/bot/__main__.py
@@ -7,10 +7,10 @@ from sentry_sdk.integrations.logging import LoggingIntegration
 
 from bot import patches
 from bot.bot import Bot
-from bot.constants import Bot as BotConfig, DEBUG_MODE
+from bot.constants import Bot as BotConfig
 
 sentry_logging = LoggingIntegration(
-    level=logging.TRACE,
+    level=logging.DEBUG,
     event_level=logging.WARNING
 )
 
@@ -31,6 +31,7 @@ bot.load_extension("bot.cogs.error_handler")
 bot.load_extension("bot.cogs.filtering")
 bot.load_extension("bot.cogs.logging")
 bot.load_extension("bot.cogs.security")
+bot.load_extension("bot.cogs.config_verifier")
 
 # Commands, etc
 bot.load_extension("bot.cogs.antimalware")
@@ -40,10 +41,8 @@ bot.load_extension("bot.cogs.clean")
 bot.load_extension("bot.cogs.extensions")
 bot.load_extension("bot.cogs.help")
 
-# Only load this in production
-if not DEBUG_MODE:
-    bot.load_extension("bot.cogs.doc")
-    bot.load_extension("bot.cogs.verification")
+bot.load_extension("bot.cogs.doc")
+bot.load_extension("bot.cogs.verification")
 
 # Feature cogs
 bot.load_extension("bot.cogs.alias")
diff --git a/bot/cogs/antimalware.py b/bot/cogs/antimalware.py
index 28e3e5d96..9e9e81364 100644
--- a/bot/cogs/antimalware.py
+++ b/bot/cogs/antimalware.py
@@ -4,7 +4,7 @@ from discord import Embed, Message, NotFound
 from discord.ext.commands import Cog
 
 from bot.bot import Bot
-from bot.constants import AntiMalware as AntiMalwareConfig, Channels, URLs
+from bot.constants import AntiMalware as AntiMalwareConfig, Channels, STAFF_ROLES, URLs
 
 log = logging.getLogger(__name__)
 
@@ -18,7 +18,13 @@ class AntiMalware(Cog):
     @Cog.listener()
     async def on_message(self, message: Message) -> None:
         """Identify messages with prohibited attachments."""
-        if not message.attachments:
+        # Return when message don't have attachment and don't moderate DMs
+        if not message.attachments or not message.guild:
+            return
+
+        # Check if user is staff, if is, return
+        # Since we only care that roles exist to iterate over, check for the attr rather than a User/Member instance
+        if hasattr(message.author, "roles") and any(role.id in STAFF_ROLES for role in message.author.roles):
             return
 
         embed = Embed()
diff --git a/bot/cogs/bot.py b/bot/cogs/bot.py
index 73b1e8f41..f17135877 100644
--- a/bot/cogs/bot.py
+++ b/bot/cogs/bot.py
@@ -34,13 +34,12 @@ class BotCog(Cog, name="Bot"):
             Channels.help_5: 0,
             Channels.help_6: 0,
             Channels.help_7: 0,
-            Channels.python: 0,
+            Channels.python_discussion: 0,
         }
 
         # These channels will also work, but will not be subject to cooldown
         self.channel_whitelist = (
-            Channels.bot,
-            Channels.devtest,
+            Channels.bot_commands,
         )
 
         # Stores improperly formatted Python codeblock message ids and the corresponding bot message
diff --git a/bot/cogs/clean.py b/bot/cogs/clean.py
index 2104efe57..5cdf0b048 100644
--- a/bot/cogs/clean.py
+++ b/bot/cogs/clean.py
@@ -173,7 +173,7 @@ class Clean(Cog):
             colour=Colour(Colours.soft_red),
             title="Bulk message delete",
             text=message,
-            channel_id=Channels.modlog,
+            channel_id=Channels.mod_log,
         )
 
     @group(invoke_without_command=True, name="clean", aliases=["purge"])
diff --git a/bot/cogs/config_verifier.py b/bot/cogs/config_verifier.py
new file mode 100644
index 000000000..d72c6c22e
--- /dev/null
+++ b/bot/cogs/config_verifier.py
@@ -0,0 +1,40 @@
+import logging
+
+from discord.ext.commands import Cog
+
+from bot import constants
+from bot.bot import Bot
+
+
+log = logging.getLogger(__name__)
+
+
+class ConfigVerifier(Cog):
+    """Verify config on startup."""
+
+    def __init__(self, bot: Bot):
+        self.bot = bot
+        self.channel_verify_task = self.bot.loop.create_task(self.verify_channels())
+
+    async def verify_channels(self) -> None:
+        """
+        Verify channels.
+
+        If any channels in config aren't present in server, log them in a warning.
+        """
+        await self.bot.wait_until_guild_available()
+        server = self.bot.get_guild(constants.Guild.id)
+
+        server_channel_ids = {channel.id for channel in server.channels}
+        invalid_channels = [
+            channel_name for channel_name, channel_id in constants.Channels
+            if channel_id not in server_channel_ids
+        ]
+
+        if invalid_channels:
+            log.warning(f"Configured channels do not exist in server: {', '.join(invalid_channels)}.")
+
+
+def setup(bot: Bot) -> None:
+    """Load the ConfigVerifier cog."""
+    bot.add_cog(ConfigVerifier(bot))
diff --git a/bot/cogs/defcon.py b/bot/cogs/defcon.py
index 20961e0a2..cc0f79fe8 100644
--- a/bot/cogs/defcon.py
+++ b/bot/cogs/defcon.py
@@ -68,8 +68,8 @@ class Defcon(Cog):
 
         except Exception:  # Yikes!
             log.exception("Unable to get DEFCON settings!")
-            await self.bot.get_channel(Channels.devlog).send(
-                f"<@&{Roles.admin}> **WARNING**: Unable to get DEFCON settings!"
+            await self.bot.get_channel(Channels.dev_log).send(
+                f"<@&{Roles.admins}> **WARNING**: Unable to get DEFCON settings!"
             )
 
         else:
@@ -118,7 +118,7 @@ class Defcon(Cog):
                 )
 
     @group(name='defcon', aliases=('dc',), invoke_without_command=True)
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def defcon_group(self, ctx: Context) -> None:
         """Check the DEFCON status or run a subcommand."""
         await ctx.invoke(self.bot.get_command("help"), "defcon")
@@ -146,7 +146,7 @@ class Defcon(Cog):
             await self.send_defcon_log(action, ctx.author, error)
 
     @defcon_group.command(name='enable', aliases=('on', 'e'))
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def enable_command(self, ctx: Context) -> None:
         """
         Enable DEFCON mode. Useful in a pinch, but be sure you know what you're doing!
@@ -159,7 +159,7 @@ class Defcon(Cog):
         await self.update_channel_topic()
 
     @defcon_group.command(name='disable', aliases=('off', 'd'))
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def disable_command(self, ctx: Context) -> None:
         """Disable DEFCON mode. Useful in a pinch, but be sure you know what you're doing!"""
         self.enabled = False
@@ -167,7 +167,7 @@ class Defcon(Cog):
         await self.update_channel_topic()
 
     @defcon_group.command(name='status', aliases=('s',))
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def status_command(self, ctx: Context) -> None:
         """Check the current status of DEFCON mode."""
         embed = Embed(
@@ -179,7 +179,7 @@ class Defcon(Cog):
         await ctx.send(embed=embed)
 
     @defcon_group.command(name='days')
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def days_command(self, ctx: Context, days: int) -> None:
         """Set how old an account must be to join the server, in days, with DEFCON mode enabled."""
         self.days = timedelta(days=days)
diff --git a/bot/cogs/error_handler.py b/bot/cogs/error_handler.py
index 0abb7e521..261769efc 100644
--- a/bot/cogs/error_handler.py
+++ b/bot/cogs/error_handler.py
@@ -1,25 +1,14 @@
 import contextlib
 import logging
+import typing as t
 
-from discord.ext.commands import (
-    BadArgument,
-    BotMissingPermissions,
-    CheckFailure,
-    CommandError,
-    CommandInvokeError,
-    CommandNotFound,
-    CommandOnCooldown,
-    DisabledCommand,
-    MissingPermissions,
-    NoPrivateMessage,
-    UserInputError,
-)
-from discord.ext.commands import Cog, Context
+from discord.ext.commands import Cog, Command, Context, errors
 from sentry_sdk import push_scope
 
 from bot.api import ResponseCodeError
 from bot.bot import Bot
 from bot.constants import Channels
+from bot.converters import TagNameConverter
 from bot.decorators import InChannelCheckFailure
 
 log = logging.getLogger(__name__)
@@ -32,118 +21,185 @@ class ErrorHandler(Cog):
         self.bot = bot
 
     @Cog.listener()
-    async def on_command_error(self, ctx: Context, e: CommandError) -> None:
+    async def on_command_error(self, ctx: Context, e: errors.CommandError) -> None:
         """
         Provide generic command error handling.
 
-        Error handling is deferred to any local error handler, if present.
-
-        Error handling emits a single error response, prioritized as follows:
-            1. If the name fails to match a command but matches a tag, the tag is invoked
-            2. Send a BadArgument error message to the invoking context & invoke the command's help
-            3. Send a UserInputError error message to the invoking context & invoke the command's help
-            4. Send a NoPrivateMessage error message to the invoking context
-            5. Send a BotMissingPermissions error message to the invoking context
-            6. Log a MissingPermissions error, no message is sent
-            7. Send a InChannelCheckFailure error message to the invoking context
-            8. Log CheckFailure, CommandOnCooldown, and DisabledCommand errors, no message is sent
-            9. For CommandInvokeErrors, response is based on the type of error:
-                * 404: Error message is sent to the invoking context
-                * 400: Log the resopnse JSON, no message is sent
-                * 500 <= status <= 600: Error message is sent to the invoking context
-            10. Otherwise, handling is deferred to `handle_unexpected_error`
+        Error handling is deferred to any local error handler, if present. This is done by
+        checking for the presence of a `handled` attribute on the error.
+
+        Error handling emits a single error message in the invoking context `ctx` and a log message,
+        prioritised as follows:
+
+        1. If the name fails to match a command but matches a tag, the tag is invoked
+            * If CommandNotFound is raised when invoking the tag (determined by the presence of the
+              `invoked_from_error_handler` attribute), this error is treated as being unexpected
+              and therefore sends an error message
+            * Commands in the verification channel are ignored
+        2. UserInputError: see `handle_user_input_error`
+        3. CheckFailure: see `handle_check_failure`
+        4. CommandOnCooldown: send an error message in the invoking context
+        5. ResponseCodeError: see `handle_api_error`
+        6. Otherwise, if not a DisabledCommand, handling is deferred to `handle_unexpected_error`
         """
         command = ctx.command
-        parent = None
 
+        if hasattr(e, "handled"):
+            log.trace(f"Command {command} had its error already handled locally; ignoring.")
+            return
+
+        # Try to look for a tag with the command's name if the command isn't found.
+        if isinstance(e, errors.CommandNotFound) and not hasattr(ctx, "invoked_from_error_handler"):
+            if ctx.channel.id != Channels.verification:
+                await self.try_get_tag(ctx)
+                return  # Exit early to avoid logging.
+        elif isinstance(e, errors.UserInputError):
+            await self.handle_user_input_error(ctx, e)
+        elif isinstance(e, errors.CheckFailure):
+            await self.handle_check_failure(ctx, e)
+        elif isinstance(e, errors.CommandOnCooldown):
+            await ctx.send(e)
+        elif isinstance(e, errors.CommandInvokeError):
+            if isinstance(e.original, ResponseCodeError):
+                await self.handle_api_error(ctx, e.original)
+            else:
+                await self.handle_unexpected_error(ctx, e.original)
+            return  # Exit early to avoid logging.
+        elif not isinstance(e, errors.DisabledCommand):
+            # ConversionError, MaxConcurrencyReached, ExtensionError
+            await self.handle_unexpected_error(ctx, e)
+            return  # Exit early to avoid logging.
+
+        log.debug(
+            f"Command {command} invoked by {ctx.message.author} with error "
+            f"{e.__class__.__name__}: {e}"
+        )
+
+    async def get_help_command(self, command: t.Optional[Command]) -> t.Tuple:
+        """Return the help command invocation args to display help for `command`."""
+        parent = None
         if command is not None:
             parent = command.parent
 
         # Retrieve the help command for the invoked command.
         if parent and command:
-            help_command = (self.bot.get_command("help"), parent.name, command.name)
+            return self.bot.get_command("help"), parent.name, command.name
         elif command:
-            help_command = (self.bot.get_command("help"), command.name)
+            return self.bot.get_command("help"), command.name
         else:
-            help_command = (self.bot.get_command("help"),)
+            return self.bot.get_command("help")
 
-        if hasattr(e, "handled"):
-            log.trace(f"Command {command} had its error already handled locally; ignoring.")
+    async def try_get_tag(self, ctx: Context) -> None:
+        """
+        Attempt to display a tag by interpreting the command name as a tag name.
+
+        The invocation of tags get respects its checks. Any CommandErrors raised will be handled
+        by `on_command_error`, but the `invoked_from_error_handler` attribute will be added to
+        the context to prevent infinite recursion in the case of a CommandNotFound exception.
+        """
+        tags_get_command = self.bot.get_command("tags get")
+        ctx.invoked_from_error_handler = True
+
+        log_msg = "Cancelling attempt to fall back to a tag due to failed checks."
+        try:
+            if not await tags_get_command.can_run(ctx):
+                log.debug(log_msg)
+                return
+        except errors.CommandError as tag_error:
+            log.debug(log_msg)
+            await self.on_command_error(ctx, tag_error)
             return
 
-        # Try to look for a tag with the command's name if the command isn't found.
-        if isinstance(e, CommandNotFound) and not hasattr(ctx, "invoked_from_error_handler"):
-            if not ctx.channel.id == Channels.verification:
-                tags_get_command = self.bot.get_command("tags get")
-                ctx.invoked_from_error_handler = True
-
-                log_msg = "Cancelling attempt to fall back to a tag due to failed checks."
-                try:
-                    if not await tags_get_command.can_run(ctx):
-                        log.debug(log_msg)
-                        return
-                except CommandError as tag_error:
-                    log.debug(log_msg)
-                    await self.on_command_error(ctx, tag_error)
-                    return
-
-                # Return to not raise the exception
-                with contextlib.suppress(ResponseCodeError):
-                    await ctx.invoke(tags_get_command, tag_name=ctx.invoked_with)
-                    return
-        elif isinstance(e, BadArgument):
+        try:
+            tag_name = await TagNameConverter.convert(ctx, ctx.invoked_with)
+        except errors.BadArgument:
+            log.debug(
+                f"{ctx.author} tried to use an invalid command "
+                f"and the fallback tag failed validation in TagNameConverter."
+            )
+        else:
+            with contextlib.suppress(ResponseCodeError):
+                await ctx.invoke(tags_get_command, tag_name=tag_name)
+        # Return to not raise the exception
+        return
+
+    async def handle_user_input_error(self, ctx: Context, e: errors.UserInputError) -> None:
+        """
+        Send an error message in `ctx` for UserInputError, sometimes invoking the help command too.
+
+        * MissingRequiredArgument: send an error message with arg name and the help command
+        * TooManyArguments: send an error message and the help command
+        * BadArgument: send an error message and the help command
+        * BadUnionArgument: send an error message including the error produced by the last converter
+        * ArgumentParsingError: send an error message
+        * Other: send an error message and the help command
+        """
+        # TODO: use ctx.send_help() once PR #519 is merged.
+        help_command = await self.get_help_command(ctx.command)
+
+        if isinstance(e, errors.MissingRequiredArgument):
+            await ctx.send(f"Missing required argument `{e.param.name}`.")
+            await ctx.invoke(*help_command)
+        elif isinstance(e, errors.TooManyArguments):
+            await ctx.send(f"Too many arguments provided.")
+            await ctx.invoke(*help_command)
+        elif isinstance(e, errors.BadArgument):
             await ctx.send(f"Bad argument: {e}\n")
             await ctx.invoke(*help_command)
-        elif isinstance(e, UserInputError):
+        elif isinstance(e, errors.BadUnionArgument):
+            await ctx.send(f"Bad argument: {e}\n```{e.errors[-1]}```")
+        elif isinstance(e, errors.ArgumentParsingError):
+            await ctx.send(f"Argument parsing error: {e}")
+        else:
             await ctx.send("Something about your input seems off. Check the arguments:")
             await ctx.invoke(*help_command)
-            log.debug(
-                f"Command {command} invoked by {ctx.message.author} with error "
-                f"{e.__class__.__name__}: {e}"
-            )
-        elif isinstance(e, NoPrivateMessage):
-            await ctx.send("Sorry, this command can't be used in a private message!")
-        elif isinstance(e, BotMissingPermissions):
-            await ctx.send(f"Sorry, it looks like I don't have the permissions I need to do that.")
-            log.warning(
-                f"The bot is missing permissions to execute command {command}: {e.missing_perms}"
-            )
-        elif isinstance(e, MissingPermissions):
-            log.debug(
-                f"{ctx.message.author} is missing permissions to invoke command {command}: "
-                f"{e.missing_perms}"
+
+    @staticmethod
+    async def handle_check_failure(ctx: Context, e: errors.CheckFailure) -> None:
+        """
+        Send an error message in `ctx` for certain types of CheckFailure.
+
+        The following types are handled:
+
+        * BotMissingPermissions
+        * BotMissingRole
+        * BotMissingAnyRole
+        * NoPrivateMessage
+        * InChannelCheckFailure
+        """
+        bot_missing_errors = (
+            errors.BotMissingPermissions,
+            errors.BotMissingRole,
+            errors.BotMissingAnyRole
+        )
+
+        if isinstance(e, bot_missing_errors):
+            await ctx.send(
+                f"Sorry, it looks like I don't have the permissions or roles I need to do that."
             )
-        elif isinstance(e, InChannelCheckFailure):
+        elif isinstance(e, (InChannelCheckFailure, errors.NoPrivateMessage)):
             await ctx.send(e)
-        elif isinstance(e, (CheckFailure, CommandOnCooldown, DisabledCommand)):
-            log.debug(
-                f"Command {command} invoked by {ctx.message.author} with error "
-                f"{e.__class__.__name__}: {e}"
-            )
-        elif isinstance(e, CommandInvokeError):
-            if isinstance(e.original, ResponseCodeError):
-                status = e.original.response.status
-
-                if status == 404:
-                    await ctx.send("There does not seem to be anything matching your query.")
-                elif status == 400:
-                    content = await e.original.response.json()
-                    log.debug(f"API responded with 400 for command {command}: %r.", content)
-                    await ctx.send("According to the API, your request is malformed.")
-                elif 500 <= status < 600:
-                    await ctx.send("Sorry, there seems to be an internal issue with the API.")
-                    log.warning(f"API responded with {status} for command {command}")
-                else:
-                    await ctx.send(f"Got an unexpected status code from the API (`{status}`).")
-                    log.warning(f"Unexpected API response for command {command}: {status}")
-            else:
-                await self.handle_unexpected_error(ctx, e.original)
+
+    @staticmethod
+    async def handle_api_error(ctx: Context, e: ResponseCodeError) -> None:
+        """Send an error message in `ctx` for ResponseCodeError and log it."""
+        if e.status == 404:
+            await ctx.send("There does not seem to be anything matching your query.")
+            log.debug(f"API responded with 404 for command {ctx.command}")
+        elif e.status == 400:
+            content = await e.response.json()
+            log.debug(f"API responded with 400 for command {ctx.command}: %r.", content)
+            await ctx.send("According to the API, your request is malformed.")
+        elif 500 <= e.status < 600:
+            await ctx.send("Sorry, there seems to be an internal issue with the API.")
+            log.warning(f"API responded with {e.status} for command {ctx.command}")
         else:
-            await self.handle_unexpected_error(ctx, e)
+            await ctx.send(f"Got an unexpected status code from the API (`{e.status}`).")
+            log.warning(f"Unexpected API response for command {ctx.command}: {e.status}")
 
     @staticmethod
-    async def handle_unexpected_error(ctx: Context, e: CommandError) -> None:
-        """Generic handler for errors without an explicit handler."""
+    async def handle_unexpected_error(ctx: Context, e: errors.CommandError) -> None:
+        """Send a generic error message in `ctx` and log the exception as an error with exc_info."""
         await ctx.send(
             f"Sorry, an unexpected error occurred. Please let us know!\n\n"
             f"```{e.__class__.__name__}: {e}```"
diff --git a/bot/cogs/eval.py b/bot/cogs/eval.py
index 9c729f28a..52136fc8d 100644
--- a/bot/cogs/eval.py
+++ b/bot/cogs/eval.py
@@ -174,14 +174,14 @@ async def func():  # (None,) -> Any
         await ctx.send(f"```py\n{out}```", embed=embed)
 
     @group(name='internal', aliases=('int',))
-    @with_role(Roles.owner, Roles.admin)
+    @with_role(Roles.owners, Roles.admins)
     async def internal_group(self, ctx: Context) -> None:
         """Internal commands. Top secret!"""
         if not ctx.invoked_subcommand:
             await ctx.invoke(self.bot.get_command("help"), "internal")
 
     @internal_group.command(name='eval', aliases=('e',))
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def eval(self, ctx: Context, *, code: str) -> None:
         """Run eval in a REPL-like format."""
         code = code.strip("`")
diff --git a/bot/cogs/extensions.py b/bot/cogs/extensions.py
index f16e79fb7..b312e1a1d 100644
--- a/bot/cogs/extensions.py
+++ b/bot/cogs/extensions.py
@@ -221,7 +221,7 @@ class Extensions(commands.Cog):
     # This cannot be static (must have a __func__ attribute).
     def cog_check(self, ctx: Context) -> bool:
         """Only allow moderators and core developers to invoke the commands in this cog."""
-        return with_role_check(ctx, *MODERATION_ROLES, Roles.core_developer)
+        return with_role_check(ctx, *MODERATION_ROLES, Roles.core_developers)
 
     # This cannot be static (must have a __func__ attribute).
     async def cog_command_error(self, ctx: Context, error: Exception) -> None:
diff --git a/bot/cogs/free.py b/bot/cogs/free.py
index 49cab6172..02c02d067 100644
--- a/bot/cogs/free.py
+++ b/bot/cogs/free.py
@@ -22,7 +22,7 @@ class Free(Cog):
     PYTHON_HELP_ID = Categories.python_help
 
     @command(name="free", aliases=('f',))
-    @redirect_output(destination_channel=Channels.bot, bypass_roles=STAFF_ROLES)
+    @redirect_output(destination_channel=Channels.bot_commands, bypass_roles=STAFF_ROLES)
     async def free(self, ctx: Context, user: Member = None, seek: int = 2) -> None:
         """
         Lists free help channels by likeliness of availability.
diff --git a/bot/cogs/help.py b/bot/cogs/help.py
index fd5bbc3ca..744722220 100644
--- a/bot/cogs/help.py
+++ b/bot/cogs/help.py
@@ -507,7 +507,7 @@ class Help(DiscordCog):
     """Custom Embed Pagination Help feature."""
 
     @commands.command('help')
-    @redirect_output(destination_channel=Channels.bot, bypass_roles=STAFF_ROLES)
+    @redirect_output(destination_channel=Channels.bot_commands, bypass_roles=STAFF_ROLES)
     async def new_help(self, ctx: Context, *commands) -> None:
         """Shows Command Help."""
         try:
diff --git a/bot/cogs/information.py b/bot/cogs/information.py
index 13c8aabaa..49beca15b 100644
--- a/bot/cogs/information.py
+++ b/bot/cogs/information.py
@@ -152,8 +152,8 @@ class Information(Cog):
 
         # Non-staff may only do this in #bot-commands
         if not with_role_check(ctx, *constants.STAFF_ROLES):
-            if not ctx.channel.id == constants.Channels.bot:
-                raise InChannelCheckFailure(constants.Channels.bot)
+            if not ctx.channel.id == constants.Channels.bot_commands:
+                raise InChannelCheckFailure(constants.Channels.bot_commands)
 
         embed = await self.create_user_embed(ctx, user)
 
@@ -332,7 +332,7 @@ class Information(Cog):
 
     @cooldown_with_role_bypass(2, 60 * 3, BucketType.member, bypass_roles=constants.STAFF_ROLES)
     @group(invoke_without_command=True)
-    @in_channel(constants.Channels.bot, bypass_roles=constants.STAFF_ROLES)
+    @in_channel(constants.Channels.bot_commands, bypass_roles=constants.STAFF_ROLES)
     async def raw(self, ctx: Context, *, message: Message, json: bool = False) -> None:
         """Shows information about the raw API response."""
         # I *guess* it could be deleted right as the command is invoked but I felt like it wasn't worth handling
diff --git a/bot/cogs/jams.py b/bot/cogs/jams.py
index 985f28ce5..1d062b0c2 100644
--- a/bot/cogs/jams.py
+++ b/bot/cogs/jams.py
@@ -18,7 +18,7 @@ class CodeJams(commands.Cog):
         self.bot = bot
 
     @commands.command()
-    @with_role(Roles.admin)
+    @with_role(Roles.admins)
     async def createteam(self, ctx: commands.Context, team_name: str, members: commands.Greedy[Member]) -> None:
         """
         Create team channels (voice and text) in the Code Jams category, assign roles, and add overwrites for the team.
@@ -95,10 +95,10 @@ class CodeJams(commands.Cog):
         )
 
         # Assign team leader role
-        await members[0].add_roles(ctx.guild.get_role(Roles.team_leader))
+        await members[0].add_roles(ctx.guild.get_role(Roles.team_leaders))
 
         # Assign rest of roles
-        jammer_role = ctx.guild.get_role(Roles.jammer)
+        jammer_role = ctx.guild.get_role(Roles.jammers)
         for member in members:
             await member.add_roles(jammer_role)
 
diff --git a/bot/cogs/logging.py b/bot/cogs/logging.py
index dbd76672f..94fa2b139 100644
--- a/bot/cogs/logging.py
+++ b/bot/cogs/logging.py
@@ -34,7 +34,7 @@ class Logging(Cog):
         )
 
         if not DEBUG_MODE:
-            await self.bot.get_channel(Channels.devlog).send(embed=embed)
+            await self.bot.get_channel(Channels.dev_log).send(embed=embed)
 
 
 def setup(bot: Bot) -> None:
diff --git a/bot/cogs/moderation/infractions.py b/bot/cogs/moderation/infractions.py
index f4e296df9..9ea17b2b3 100644
--- a/bot/cogs/moderation/infractions.py
+++ b/bot/cogs/moderation/infractions.py
@@ -313,6 +313,6 @@ class Infractions(InfractionScheduler, commands.Cog):
     async def cog_command_error(self, ctx: Context, error: Exception) -> None:
         """Send a notification to the invoking context on a Union failure."""
         if isinstance(error, commands.BadUnionArgument):
-            if discord.User in error.converters:
+            if discord.User in error.converters or discord.Member in error.converters:
                 await ctx.send(str(error.errors[0]))
                 error.handled = True
diff --git a/bot/cogs/moderation/management.py b/bot/cogs/moderation/management.py
index 279c8b809..35448f682 100644
--- a/bot/cogs/moderation/management.py
+++ b/bot/cogs/moderation/management.py
@@ -128,7 +128,9 @@ class ModManagement(commands.Cog):
 
         # Re-schedule infraction if the expiration has been updated
         if 'expires_at' in request_data:
-            self.infractions_cog.cancel_task(new_infraction['id'])
+            # A scheduled task should only exist if the old infraction wasn't permanent
+            if old_infraction['expires_at']:
+                self.infractions_cog.cancel_task(new_infraction['id'])
 
             # If the infraction was not marked as permanent, schedule a new expiration task
             if request_data['expires_at']:
diff --git a/bot/cogs/moderation/modlog.py b/bot/cogs/moderation/modlog.py
index e8ae0dbe6..59ae6b587 100644
--- a/bot/cogs/moderation/modlog.py
+++ b/bot/cogs/moderation/modlog.py
@@ -87,7 +87,7 @@ class ModLog(Cog, name="ModLog"):
         title: t.Optional[str],
         text: str,
         thumbnail: t.Optional[t.Union[str, discord.Asset]] = None,
-        channel_id: int = Channels.modlog,
+        channel_id: int = Channels.mod_log,
         ping_everyone: bool = False,
         files: t.Optional[t.List[discord.File]] = None,
         content: t.Optional[str] = None,
@@ -377,7 +377,7 @@ class ModLog(Cog, name="ModLog"):
             Icons.user_ban, Colours.soft_red,
             "User banned", f"{member} (`{member.id}`)",
             thumbnail=member.avatar_url_as(static_format="png"),
-            channel_id=Channels.userlog
+            channel_id=Channels.user_log
         )
 
     @Cog.listener()
@@ -399,7 +399,7 @@ class ModLog(Cog, name="ModLog"):
             Icons.sign_in, Colours.soft_green,
             "User joined", message,
             thumbnail=member.avatar_url_as(static_format="png"),
-            channel_id=Channels.userlog
+            channel_id=Channels.user_log
         )
 
     @Cog.listener()
@@ -416,7 +416,7 @@ class ModLog(Cog, name="ModLog"):
             Icons.sign_out, Colours.soft_red,
             "User left", f"{member} (`{member.id}`)",
             thumbnail=member.avatar_url_as(static_format="png"),
-            channel_id=Channels.userlog
+            channel_id=Channels.user_log
         )
 
     @Cog.listener()
@@ -433,7 +433,7 @@ class ModLog(Cog, name="ModLog"):
             Icons.user_unban, Colour.blurple(),
             "User unbanned", f"{member} (`{member.id}`)",
             thumbnail=member.avatar_url_as(static_format="png"),
-            channel_id=Channels.modlog
+            channel_id=Channels.mod_log
         )
 
     @Cog.listener()
@@ -529,7 +529,7 @@ class ModLog(Cog, name="ModLog"):
             Icons.user_update, Colour.blurple(),
             "Member updated", message,
             thumbnail=after.avatar_url_as(static_format="png"),
-            channel_id=Channels.userlog
+            channel_id=Channels.user_log
         )
 
     @Cog.listener()
@@ -538,7 +538,7 @@ class ModLog(Cog, name="ModLog"):
         channel = message.channel
         author = message.author
 
-        if message.guild.id != GuildConstant.id or channel.id in GuildConstant.ignored:
+        if message.guild.id != GuildConstant.id or channel.id in GuildConstant.modlog_blacklist:
             return
 
         self._cached_deletes.append(message.id)
@@ -591,7 +591,7 @@ class ModLog(Cog, name="ModLog"):
     @Cog.listener()
     async def on_raw_message_delete(self, event: discord.RawMessageDeleteEvent) -> None:
         """Log raw message delete event to message change log."""
-        if event.guild_id != GuildConstant.id or event.channel_id in GuildConstant.ignored:
+        if event.guild_id != GuildConstant.id or event.channel_id in GuildConstant.modlog_blacklist:
             return
 
         await asyncio.sleep(1)  # Wait here in case the normal event was fired
@@ -635,7 +635,7 @@ class ModLog(Cog, name="ModLog"):
         if (
             not msg_before.guild
             or msg_before.guild.id != GuildConstant.id
-            or msg_before.channel.id in GuildConstant.ignored
+            or msg_before.channel.id in GuildConstant.modlog_blacklist
             or msg_before.author.bot
         ):
             return
@@ -717,7 +717,7 @@ class ModLog(Cog, name="ModLog"):
         if (
             not message.guild
             or message.guild.id != GuildConstant.id
-            or message.channel.id in GuildConstant.ignored
+            or message.channel.id in GuildConstant.modlog_blacklist
             or message.author.bot
         ):
             return
@@ -769,7 +769,7 @@ class ModLog(Cog, name="ModLog"):
         """Log member voice state changes to the voice log channel."""
         if (
             member.guild.id != GuildConstant.id
-            or (before.channel and before.channel.id in GuildConstant.ignored)
+            or (before.channel and before.channel.id in GuildConstant.modlog_blacklist)
         ):
             return
 
diff --git a/bot/cogs/moderation/scheduler.py b/bot/cogs/moderation/scheduler.py
index 93afd9f9f..f0b6b2c48 100644
--- a/bot/cogs/moderation/scheduler.py
+++ b/bot/cogs/moderation/scheduler.py
@@ -308,7 +308,7 @@ class InfractionScheduler(Scheduler):
         Infractions of unsupported types will raise a ValueError.
         """
         guild = self.bot.get_guild(constants.Guild.id)
-        mod_role = guild.get_role(constants.Roles.moderator)
+        mod_role = guild.get_role(constants.Roles.moderators)
         user_id = infraction["user"]
         actor = infraction["actor"]
         type_ = infraction["type"]
diff --git a/bot/cogs/reddit.py b/bot/cogs/reddit.py
index 4f6584aba..5a7fa100f 100644
--- a/bot/cogs/reddit.py
+++ b/bot/cogs/reddit.py
@@ -43,8 +43,8 @@ class Reddit(Cog):
     def cog_unload(self) -> None:
         """Stop the loop task and revoke the access token when the cog is unloaded."""
         self.auto_poster_loop.cancel()
-        if self.access_token.expires_at < datetime.utcnow():
-            self.revoke_access_token()
+        if self.access_token and self.access_token.expires_at > datetime.utcnow():
+            asyncio.create_task(self.revoke_access_token())
 
     async def init_reddit_ready(self) -> None:
         """Sets the reddit webhook when the cog is loaded."""
@@ -83,7 +83,7 @@ class Reddit(Cog):
                     expires_at=datetime.utcnow() + timedelta(seconds=expiration)
                 )
 
-                log.debug(f"New token acquired; expires on {self.access_token.expires_at}")
+                log.debug(f"New token acquired; expires on UTC {self.access_token.expires_at}")
                 return
             else:
                 log.debug(
@@ -290,4 +290,7 @@ class Reddit(Cog):
 
 def setup(bot: Bot) -> None:
     """Load the Reddit cog."""
+    if not RedditConfig.secret or not RedditConfig.client_id:
+        log.error("Credentials not provided, cog not loaded.")
+        return
     bot.add_cog(Reddit(bot))
diff --git a/bot/cogs/snekbox.py b/bot/cogs/snekbox.py
index da33e27b2..cff7c5786 100644
--- a/bot/cogs/snekbox.py
+++ b/bot/cogs/snekbox.py
@@ -1,10 +1,14 @@
+import asyncio
+import contextlib
 import datetime
 import logging
 import re
 import textwrap
+from functools import partial
 from signal import Signals
 from typing import Optional, Tuple
 
+from discord import HTTPException, Message, NotFound, Reaction, User
 from discord.ext.commands import Cog, Context, command, guild_only
 
 from bot.bot import Bot
@@ -34,7 +38,11 @@ RAW_CODE_REGEX = re.compile(
 )
 
 MAX_PASTE_LEN = 1000
-EVAL_ROLES = (Roles.helpers, Roles.moderator, Roles.admin, Roles.owner, Roles.rockstars, Roles.partners)
+EVAL_ROLES = (Roles.helpers, Roles.moderators, Roles.admins, Roles.owners, Roles.python_community, Roles.partners)
+
+SIGKILL = 9
+
+REEVAL_EMOJI = '\U0001f501'  # :repeat:
 
 
 class Snekbox(Cog):
@@ -101,7 +109,7 @@ class Snekbox(Cog):
         if returncode is None:
             msg = "Your eval job has failed"
             error = stdout.strip()
-        elif returncode == 128 + Signals.SIGKILL:
+        elif returncode == 128 + SIGKILL:
             msg = "Your eval job timed out or ran out of memory"
         elif returncode == 255:
             msg = "Your eval job has failed"
@@ -135,7 +143,7 @@ class Snekbox(Cog):
         """
         log.trace("Formatting output...")
 
-        output = output.strip(" \n")
+        output = output.rstrip("\n")
         original_output = output  # To be uploaded to a pasting service if needed
         paste_link = None
 
@@ -152,8 +160,8 @@ class Snekbox(Cog):
         lines = output.count("\n")
 
         if lines > 0:
-            output = output.split("\n")[:10]  # Only first 10 cause the rest is truncated anyway
-            output = (f"{i:03d} | {line}" for i, line in enumerate(output, 1))
+            output = [f"{i:03d} | {line}" for i, line in enumerate(output.split('\n'), 1)]
+            output = output[:11]  # Limiting to only 11 lines
             output = "\n".join(output)
 
         if lines > 10:
@@ -169,21 +177,84 @@ class Snekbox(Cog):
         if truncated:
             paste_link = await self.upload_output(original_output)
 
-        output = output.strip()
-        if not output:
-            output = "[No output]"
+        output = output or "[No output]"
 
         return output, paste_link
 
+    async def send_eval(self, ctx: Context, code: str) -> Message:
+        """
+        Evaluate code, format it, and send the output to the corresponding channel.
+
+        Return the bot response.
+        """
+        async with ctx.typing():
+            results = await self.post_eval(code)
+            msg, error = self.get_results_message(results)
+
+            if error:
+                output, paste_link = error, None
+            else:
+                output, paste_link = await self.format_output(results["stdout"])
+
+            icon = self.get_status_emoji(results)
+            msg = f"{ctx.author.mention} {icon} {msg}.\n\n```py\n{output}\n```"
+            if paste_link:
+                msg = f"{msg}\nFull output: {paste_link}"
+
+            response = await ctx.send(msg)
+            self.bot.loop.create_task(
+                wait_for_deletion(response, user_ids=(ctx.author.id,), client=ctx.bot)
+            )
+
+            log.info(f"{ctx.author}'s job had a return code of {results['returncode']}")
+        return response
+
+    async def continue_eval(self, ctx: Context, response: Message) -> Optional[str]:
+        """
+        Check if the eval session should continue.
+
+        Return the new code to evaluate or None if the eval session should be terminated.
+        """
+        _predicate_eval_message_edit = partial(predicate_eval_message_edit, ctx)
+        _predicate_emoji_reaction = partial(predicate_eval_emoji_reaction, ctx)
+
+        with contextlib.suppress(NotFound):
+            try:
+                _, new_message = await self.bot.wait_for(
+                    'message_edit',
+                    check=_predicate_eval_message_edit,
+                    timeout=10
+                )
+                await ctx.message.add_reaction(REEVAL_EMOJI)
+                await self.bot.wait_for(
+                    'reaction_add',
+                    check=_predicate_emoji_reaction,
+                    timeout=10
+                )
+
+                code = new_message.content.split(' ', maxsplit=1)[1]
+                await ctx.message.clear_reactions()
+                with contextlib.suppress(HTTPException):
+                    await response.delete()
+
+            except asyncio.TimeoutError:
+                await ctx.message.clear_reactions()
+                return None
+
+            return code
+
     @command(name="eval", aliases=("e",))
     @guild_only()
-    @in_channel(Channels.bot, hidden_channels=(Channels.esoteric,), bypass_roles=EVAL_ROLES)
+    @in_channel(Channels.bot_commands, hidden_channels=(Channels.esoteric,), bypass_roles=EVAL_ROLES)
     async def eval_command(self, ctx: Context, *, code: str = None) -> None:
         """
         Run Python code and get the results.
 
         This command supports multiple lines of code, including code wrapped inside a formatted code
-        block. We've done our best to make this safe, but do let us know if you manage to find an
+        block. Code can be re-evaluated by editing the original message within 10 seconds and
+        clicking the reaction that subsequently appears.
+
+        We've done our best to make this sandboxed, but do let us know if you manage to find an
         issue with it!
         """
         if ctx.author.id in self.jobs:
@@ -199,32 +270,28 @@ class Snekbox(Cog):
 
         log.info(f"Received code from {ctx.author} for evaluation:\n{code}")
 
-        self.jobs[ctx.author.id] = datetime.datetime.now()
-        code = self.prepare_input(code)
+        while True:
+            self.jobs[ctx.author.id] = datetime.datetime.now()
+            code = self.prepare_input(code)
+            try:
+                response = await self.send_eval(ctx, code)
+            finally:
+                del self.jobs[ctx.author.id]
+
+            code = await self.continue_eval(ctx, response)
+            if not code:
+                break
+            log.info(f"Re-evaluating message {ctx.message.id}")
+
+
+def predicate_eval_message_edit(ctx: Context, old_msg: Message, new_msg: Message) -> bool:
+    """Return True if the edited message is the context message and the content was indeed modified."""
+    return new_msg.id == ctx.message.id and old_msg.content != new_msg.content
 
-        try:
-            async with ctx.typing():
-                results = await self.post_eval(code)
-                msg, error = self.get_results_message(results)
-
-                if error:
-                    output, paste_link = error, None
-                else:
-                    output, paste_link = await self.format_output(results["stdout"])
-
-                icon = self.get_status_emoji(results)
-                msg = f"{ctx.author.mention} {icon} {msg}.\n\n```py\n{output}\n```"
-                if paste_link:
-                    msg = f"{msg}\nFull output: {paste_link}"
-
-                response = await ctx.send(msg)
-                self.bot.loop.create_task(
-                    wait_for_deletion(response, user_ids=(ctx.author.id,), client=ctx.bot)
-                )
 
-                log.info(f"{ctx.author}'s job had a return code of {results['returncode']}")
-        finally:
-            del self.jobs[ctx.author.id]
+def predicate_eval_emoji_reaction(ctx: Context, reaction: Reaction, user: User) -> bool:
+    """Return True if the reaction REEVAL_EMOJI was added by the context message author on this message."""
+    return reaction.message.id == ctx.message.id and user.id == ctx.author.id and str(reaction) == REEVAL_EMOJI
 
 
 def setup(bot: Bot) -> None:
diff --git a/bot/cogs/sync/syncers.py b/bot/cogs/sync/syncers.py
index 6715ad6fb..d6891168f 100644
--- a/bot/cogs/sync/syncers.py
+++ b/bot/cogs/sync/syncers.py
@@ -23,7 +23,7 @@ _Diff = namedtuple('Diff', ('created', 'updated', 'deleted'))
 class Syncer(abc.ABC):
     """Base class for synchronising the database with objects in the Discord cache."""
 
-    _CORE_DEV_MENTION = f"<@&{constants.Roles.core_developer}> "
+    _CORE_DEV_MENTION = f"<@&{constants.Roles.core_developers}> "
     _REACTION_EMOJIS = (constants.Emojis.check_mark, constants.Emojis.cross_mark)
 
     def __init__(self, bot: Bot) -> None:
@@ -54,12 +54,12 @@ class Syncer(abc.ABC):
         # Send to core developers if it's an automatic sync.
         if not message:
             log.trace("Message not provided for confirmation; creating a new one in dev-core.")
-            channel = self.bot.get_channel(constants.Channels.devcore)
+            channel = self.bot.get_channel(constants.Channels.dev_core)
 
             if not channel:
                 log.debug("Failed to get the dev-core channel from cache; attempting to fetch it.")
                 try:
-                    channel = await self.bot.fetch_channel(constants.Channels.devcore)
+                    channel = await self.bot.fetch_channel(constants.Channels.dev_core)
                 except HTTPException:
                     log.exception(
                         f"Failed to fetch channel for sending sync confirmation prompt; "
@@ -93,7 +93,7 @@ class Syncer(abc.ABC):
         `author` of the prompt.
         """
         # For automatic syncs, check for the core dev role instead of an exact author
-        has_role = any(constants.Roles.core_developer == role.id for role in user.roles)
+        has_role = any(constants.Roles.core_developers == role.id for role in user.roles)
         return (
             reaction.message.id == message.id
             and not user.bot
diff --git a/bot/cogs/tags.py b/bot/cogs/tags.py
index b6360dfae..5da9a4148 100644
--- a/bot/cogs/tags.py
+++ b/bot/cogs/tags.py
@@ -15,8 +15,7 @@ from bot.pagination import LinePaginator
 log = logging.getLogger(__name__)
 
 TEST_CHANNELS = (
-    Channels.devtest,
-    Channels.bot,
+    Channels.bot_commands,
     Channels.helpers
 )
 
@@ -221,7 +220,7 @@ class Tags(Cog):
         ))
 
     @tags_group.command(name='delete', aliases=('remove', 'rm', 'd'))
-    @with_role(Roles.admin, Roles.owner)
+    @with_role(Roles.admins, Roles.owners)
     async def delete_command(self, ctx: Context, *, tag_name: TagNameConverter) -> None:
         """Remove a tag from the database."""
         await self.bot.api_client.delete(f'bot/tags/{tag_name}')
diff --git a/bot/cogs/utils.py b/bot/cogs/utils.py
index da278011a..94b9d6b5a 100644
--- a/bot/cogs/utils.py
+++ b/bot/cogs/utils.py
@@ -89,7 +89,7 @@ class Utils(Cog):
         await ctx.message.channel.send(embed=pep_embed)
 
     @command()
-    @in_channel(Channels.bot, bypass_roles=STAFF_ROLES)
+    @in_channel(Channels.bot_commands, bypass_roles=STAFF_ROLES)
     async def charinfo(self, ctx: Context, *, characters: str) -> None:
         """Shows you information on up to 25 unicode characters."""
         match = re.match(r"<(a?):(\w+):(\d+)>", characters)
diff --git a/bot/cogs/verification.py b/bot/cogs/verification.py
index e3c396863..57b50c34f 100644
--- a/bot/cogs/verification.py
+++ b/bot/cogs/verification.py
@@ -30,15 +30,16 @@ your information removed here as well.
 Feel free to review them at any point!
 
 Additionally, if you'd like to receive notifications for the announcements we post in <#{Channels.announcements}> \
-from time to time, you can send `!subscribe` to <#{Channels.bot}> at any time to assign yourself the \
+from time to time, you can send `!subscribe` to <#{Channels.bot_commands}> at any time to assign yourself the \
 **Announcements** role. We'll mention this role every time we make an announcement.
 
-If you'd like to unsubscribe from the announcement notifications, simply send `!unsubscribe` to <#{Channels.bot}>.
+If you'd like to unsubscribe from the announcement notifications, simply send `!unsubscribe` to \
+<#{Channels.bot_commands}>.
 """
 
 PERIODIC_PING = (
     f"@everyone To verify that you have read our rules, please type `{BotConfig.prefix}accept`."
-    f" If you encounter any problems during the verification process, ping the <@&{Roles.admin}> role in this channel."
+    f" If you encounter any problems during the verification process, ping the <@&{Roles.admins}> role in this channel."
 )
 BOT_MESSAGE_DELETE_DELAY = 10
 
@@ -136,7 +137,7 @@ class Verification(Cog):
                 await ctx.message.delete()
 
     @command(name='subscribe')
-    @in_channel(Channels.bot)
+    @in_channel(Channels.bot_commands)
     async def subscribe_command(self, ctx: Context, *_) -> None:  # We don't actually care about the args
         """Subscribe to announcement notifications by assigning yourself the role."""
         has_role = False
@@ -160,7 +161,7 @@ class Verification(Cog):
         )
 
     @command(name='unsubscribe')
-    @in_channel(Channels.bot)
+    @in_channel(Channels.bot_commands)
     async def unsubscribe_command(self, ctx: Context, *_) -> None:  # We don't actually care about the args
         """Unsubscribe from announcement notifications by removing the role from yourself."""
         has_role = False
diff --git a/bot/constants.py b/bot/constants.py
index 9bc331dc4..14f8dc094 100644
--- a/bot/constants.py
+++ b/bot/constants.py
@@ -186,6 +186,11 @@ class YAMLGetter(type):
     def __getitem__(cls, name):
         return cls.__getattr__(name)
 
+    def __iter__(cls):
+        """Return generator of key: value pairs of current constants class' config values."""
+        for name in cls.__annotations__:
+            yield name, getattr(cls, name)
+
 
 # Dataclasses
 class Bot(metaclass=YAMLGetter):
@@ -358,18 +363,16 @@ class Channels(metaclass=YAMLGetter):
     section = "guild"
     subsection = "channels"
 
-    admins: int
     admin_spam: int
+    admins: int
     announcements: int
     attachment_log: int
     big_brother_logs: int
-    bot: int
-    checkpoint_test: int
+    bot_commands: int
     defcon: int
-    devcontrib: int
-    devcore: int
-    devlog: int
-    devtest: int
+    dev_contrib: int
+    dev_core: int
+    dev_log: int
     esoteric: int
     help_0: int
     help_1: int
@@ -382,19 +385,19 @@ class Channels(metaclass=YAMLGetter):
     helpers: int
     message_log: int
     meta: int
+    mod_alerts: int
+    mod_log: int
     mod_spam: int
     mods: int
-    mod_alerts: int
-    modlog: int
     off_topic_0: int
     off_topic_1: int
     off_topic_2: int
     organisation: int
-    python: int
+    python_discussion: int
     reddit: int
     talent_pool: int
-    userlog: int
-    user_event_a: int
+    user_event_announcements: int
+    user_log: int
     verification: int
     voice_log: int
 
@@ -414,19 +417,18 @@ class Roles(metaclass=YAMLGetter):
     section = "guild"
     subsection = "roles"
 
-    admin: int
+    admins: int
     announcements: int
-    champion: int
-    contributor: int
-    core_developer: int
+    contributors: int
+    core_developers: int
     helpers: int
-    jammer: int
-    moderator: int
+    jammers: int
+    moderators: int
     muted: int
-    owner: int
+    owners: int
     partners: int
-    rockstars: int
-    team_leader: int
+    python_community: int
+    team_leaders: int
     verified: int  # This is the Developers role on PyDis, here named verified for readability reasons.
 
 
@@ -434,9 +436,12 @@ class Guild(metaclass=YAMLGetter):
     section = "guild"
 
     id: int
-    ignored: List[int]
-    staff_channels: List[int]
+    moderation_channels: List[int]
+    moderation_roles: List[int]
+    modlog_blacklist: List[int]
     reminder_whitelist: List[int]
+    staff_channels: List[int]
+    staff_roles: List[int]
 
 class Keys(metaclass=YAMLGetter):
     section = "keys"
@@ -582,14 +587,14 @@ BOT_DIR = os.path.dirname(__file__)
 PROJECT_ROOT = os.path.abspath(os.path.join(BOT_DIR, os.pardir))
 
 # Default role combinations
-MODERATION_ROLES = Roles.moderator, Roles.admin, Roles.owner
-STAFF_ROLES = Roles.helpers, Roles.moderator, Roles.admin, Roles.owner
+MODERATION_ROLES = Guild.moderation_roles
+STAFF_ROLES = Guild.staff_roles
 
 # Roles combinations
 STAFF_CHANNELS = Guild.staff_channels
 
 # Default Channel combinations
-MODERATION_CHANNELS = Channels.admins, Channels.admin_spam, Channels.mod_alerts, Channels.mods, Channels.mod_spam
+MODERATION_CHANNELS = Guild.moderation_channels
 
 
 # Bot replies
diff --git a/bot/converters.py b/bot/converters.py
index cca57a02d..1945e1da3 100644
--- a/bot/converters.py
+++ b/bot/converters.py
@@ -141,40 +141,24 @@ class TagNameConverter(Converter):
     @staticmethod
     async def convert(ctx: Context, tag_name: str) -> str:
         """Lowercase & strip whitespace from proposed tag_name & ensure it's valid."""
-        def is_number(value: str) -> bool:
-            """Check to see if the input string is numeric."""
-            try:
-                float(value)
-            except ValueError:
-                return False
-            return True
-
         tag_name = tag_name.lower().strip()
 
         # The tag name has at least one invalid character.
         if ascii(tag_name)[1:-1] != tag_name:
-            log.warning(f"{ctx.author} tried to put an invalid character in a tag name. "
-                        "Rejecting the request.")
             raise BadArgument("Don't be ridiculous, you can't use that character!")
 
         # The tag name is either empty, or consists of nothing but whitespace.
         elif not tag_name:
-            log.warning(f"{ctx.author} tried to create a tag with a name consisting only of whitespace. "
-                        "Rejecting the request.")
             raise BadArgument("Tag names should not be empty, or filled with whitespace.")
 
-        # The tag name is a number of some kind, we don't allow that.
-        elif is_number(tag_name):
-            log.warning(f"{ctx.author} tried to create a tag with a digit as its name. "
-                        "Rejecting the request.")
-            raise BadArgument("Tag names can't be numbers.")
-
         # The tag name is longer than 127 characters.
         elif len(tag_name) > 127:
-            log.warning(f"{ctx.author} tried to request a tag name with over 127 characters. "
-                        "Rejecting the request.")
             raise BadArgument("Are you insane? That's way too long!")
 
+        # The tag name is ascii but does not contain any letters.
+        elif not any(character.isalpha() for character in tag_name):
+            raise BadArgument("Tag names must contain at least one letter.")
+
         return tag_name
 
 
@@ -192,8 +176,6 @@ class TagContentConverter(Converter):
 
         # The tag contents should not be empty, or filled with whitespace.
         if not tag_content:
-            log.warning(f"{ctx.author} tried to create a tag containing only whitespace. "
-                        "Rejecting the request.")
             raise BadArgument("Tag contents should not be empty, or filled with whitespace.")
 
         return tag_content
diff --git a/bot/utils/__init__.py b/bot/utils/__init__.py
index 8184be824..3e4b15ce4 100644
--- a/bot/utils/__init__.py
+++ b/bot/utils/__init__.py
@@ -1,5 +1,5 @@
 from abc import ABCMeta
-from typing import Any, Generator, Hashable, Iterable
+from typing import Any, Hashable
 
 from discord.ext.commands import CogMeta
 
@@ -64,13 +64,3 @@ class CaseInsensitiveDict(dict):
         for k in list(self.keys()):
             v = super(CaseInsensitiveDict, self).pop(k)
             self.__setitem__(k, v)
-
-
-def chunks(iterable: Iterable, size: int) -> Generator[Any, None, None]:
-    """
-    Generator that allows you to iterate over any indexable collection in `size`-length chunks.
-
-    Found: https://stackoverflow.com/a/312464/4022104
-    """
-    for i in range(0, len(iterable), size):
-        yield iterable[i:i + size]
diff --git a/config-default.yml b/config-default.yml
index f70fe3c34..ab237423f 100644
--- a/config-default.yml
+++ b/config-default.yml
@@ -111,78 +111,135 @@ guild:
     id: 267624335836053506
 
     categories:
-        python_help:                      356013061213126657
+        python_help:    356013061213126657
 
     channels:
-        admins:            &ADMINS        365960823622991872
-        admin_spam:        &ADMIN_SPAM    563594791770914816
-        admins_voice:      &ADMINS_VOICE  500734494840717332
-        announcements:                    354619224620138496
-        attachment_log:    &ATTCH_LOG     649243850006855680
-        big_brother_logs:  &BBLOGS        468507907357409333
-        bot:               &BOT_CMD       267659945086812160
-        checkpoint_test:                  422077681434099723
-        defcon:            &DEFCON        464469101889454091
-        devcontrib:        &DEV_CONTRIB   635950537262759947
-        devcore:                          411200599653351425
-        devlog:            &DEVLOG        622895325144940554
-        devtest:           &DEVTEST       414574275865870337
-        esoteric:                         470884583684964352
-        help_0:                           303906576991780866
-        help_1:                           303906556754395136
-        help_2:                           303906514266226689
-        help_3:                           439702951246692352
-        help_4:                           451312046647148554
-        help_5:                           454941769734422538
-        help_6:                           587375753306570782
-        help_7:                           587375768556797982
-        helpers:           &HELPERS       385474242440986624
-        message_log:       &MESSAGE_LOG   467752170159079424
-        meta:                             429409067623251969
-        mod_spam:          &MOD_SPAM      620607373828030464
-        mods:              &MODS          305126844661760000
-        mod_alerts:                       473092532147060736
-        modlog:            &MODLOG        282638479504965634
-        off_topic_0:                      291284109232308226
-        off_topic_1:                      463035241142026251
-        off_topic_2:                      463035268514185226
-        organisation:      &ORGANISATION  551789653284356126
-        python:                           267624335836053506
-        reddit:                           458224812528238616
-        staff_lounge:      &STAFF_LOUNGE  464905259261755392
-        staff_voice:       &STAFF_VOICE   412375055910043655
-        talent_pool:       &TALENT_POOL   534321732593647616
-        userlog:                          528976905546760203
-        user_event_a:      &USER_EVENT_A  592000283102674944
-        verification:                     352442727016693763
-        voice_log:                        640292421988646961
-
-    staff_channels: [*ADMINS, *ADMIN_SPAM, *MOD_SPAM, *MODS, *HELPERS, *ORGANISATION, *DEFCON]
-    ignored: [*ADMINS, *MESSAGE_LOG, *MODLOG, *ADMINS_VOICE, *STAFF_VOICE, *ATTCH_LOG]
-    reminder_whitelist: [*BOT_CMD, *DEV_CONTRIB]
+        announcements:                              354619224620138496
+        user_event_announcements:   &USER_EVENT_A   592000283102674944
+
+        # Development
+        dev_contrib:        &DEV_CONTRIB    635950537262759947
+        dev_core:           &DEV_CORE       411200599653351425
+        dev_log:            &DEV_LOG        622895325144940554
+
+        # Discussion
+        meta:               429409067623251969
+        python_discussion:  267624335836053506
+
+        # Logs
+        attachment_log:     &ATTACH_LOG     649243850006855680
+        message_log:        &MESSAGE_LOG    467752170159079424
+        mod_log:            &MOD_LOG        282638479504965634
+        user_log:                           528976905546760203
+        voice_log:                          640292421988646961
+
+        # Off-topic
+        off_topic_0:    291284109232308226
+        off_topic_1:    463035241142026251
+        off_topic_2:    463035268514185226
+
+        # Python Help
+        help_0:         303906576991780866
+        help_1:         303906556754395136
+        help_2:         303906514266226689
+        help_3:         439702951246692352
+        help_4:         451312046647148554
+        help_5:         454941769734422538
+        help_6:         587375753306570782
+        help_7:         587375768556797982
+
+        # Special
+        bot_commands:       &BOT_CMD        267659945086812160
+        esoteric:                           470884583684964352
+        reddit:                             458224812528238616
+        verification:                       352442727016693763
+
+        # Staff
+        admins:             &ADMINS         365960823622991872
+        admin_spam:         &ADMIN_SPAM     563594791770914816
+        defcon:             &DEFCON         464469101889454091
+        helpers:            &HELPERS        385474242440986624
+        mods:               &MODS           305126844661760000
+        mod_alerts:         &MOD_ALERTS     473092532147060736
+        mod_spam:           &MOD_SPAM       620607373828030464
+        organisation:       &ORGANISATION   551789653284356126
+        staff_lounge:       &STAFF_LOUNGE   464905259261755392
+
+        # Voice
+        admins_voice:       &ADMINS_VOICE   500734494840717332
+        staff_voice:        &STAFF_VOICE    412375055910043655
+
+        # Watch
+        big_brother_logs:   &BB_LOGS        468507907357409333
+        talent_pool:        &TALENT_POOL    534321732593647616
+
+    staff_channels:
+        - *ADMINS
+        - *ADMIN_SPAM
+        - *DEFCON
+        - *HELPERS
+        - *MODS
+        - *MOD_SPAM
+        - *ORGANISATION
+
+    moderation_channels:
+        - *ADMINS
+        - *ADMIN_SPAM
+        - *MOD_ALERTS
+        - *MODS
+        - *MOD_SPAM
+
+    # Modlog cog ignores events which occur in these channels
+    modlog_blacklist:
+        - *ADMINS
+        - *ADMINS_VOICE
+        - *ATTACH_LOG
+        - *MESSAGE_LOG
+        - *MOD_LOG
+        - *STAFF_VOICE
+
+    reminder_whitelist:
+        - *BOT_CMD
+        - *DEV_CONTRIB
 
     roles:
-        admin:             &ADMIN_ROLE      267628507062992896
-        announcements:                      463658397560995840
-        champion:                           430492892331769857
-        contributor:                        295488872404484098
-        core_developer:                     587606783669829632
-        helpers:                            267630620367257601
-        jammer:                             591786436651646989
-        moderator:         &MOD_ROLE        267629731250176001
-        muted:             &MUTED_ROLE      277914926603829249
-        owner:             &OWNER_ROLE      267627879762755584
-        partners:                           323426753857191936
-        rockstars:         &ROCKSTARS_ROLE  458226413825294336
-        team_leader:                        501324292341104650
-        verified:                           352427296948486144
+        announcements:                          463658397560995840
+        contributors:                           295488872404484098
+        muted:              &MUTED_ROLE         277914926603829249
+        partners:                               323426753857191936
+        python_community:   &PY_COMMUNITY_ROLE  458226413825294336
+
+        # This is the Developers role on PyDis, here named verified for readability reasons
+        verified:                               352427296948486144
+
+        # Staff
+        admins:             &ADMINS_ROLE    267628507062992896
+        core_developers:                    587606783669829632
+        helpers:            &HELPERS_ROLE   267630620367257601
+        moderators:         &MODS_ROLE      267629731250176001
+        owners:             &OWNERS_ROLE    267627879762755584
+
+        # Code Jam
+        jammers:        591786436651646989
+        team_leaders:   501324292341104650
+
+    moderation_roles:
+        - *OWNERS_ROLE
+        - *ADMINS_ROLE
+        - *MODS_ROLE
+
+    staff_roles:
+        - *OWNERS_ROLE
+        - *ADMINS_ROLE
+        - *MODS_ROLE
+        - *HELPERS_ROLE
 
     webhooks:
-        talent_pool:                        569145364800602132
-        big_brother:                        569133704568373283
-        reddit:                             635408384794951680
-        duck_pond:                          637821475327311927
-        dev_log:                            680501655111729222
+        talent_pool:    569145364800602132
+        big_brother:    569133704568373283
+        reddit:         635408384794951680
+        duck_pond:      637821475327311927
+        dev_log:        680501655111729222
 
 
 filter:
@@ -260,20 +317,19 @@ filter:
     # Censor doesn't apply to these
     channel_whitelist:
         - *ADMINS
-        - *MODLOG
+        - *MOD_LOG
         - *MESSAGE_LOG
-        - *DEVLOG
-        - *BBLOGS
+        - *DEV_LOG
+        - *BB_LOGS
         - *STAFF_LOUNGE
-        - *DEVTEST
         - *TALENT_POOL
         - *USER_EVENT_A
 
     role_whitelist:
-        - *ADMIN_ROLE
-        - *MOD_ROLE
-        - *OWNER_ROLE
-        - *ROCKSTARS_ROLE
+        - *ADMINS_ROLE
+        - *MODS_ROLE
+        - *OWNERS_ROLE
+        - *PY_COMMUNITY_ROLE
 
 
 keys:
@@ -441,7 +497,20 @@ sync:
 
 duck_pond:
     threshold: 5
-    custom_emojis: [*DUCKY_YELLOW, *DUCKY_BLURPLE, *DUCKY_CAMO, *DUCKY_DEVIL, *DUCKY_NINJA, *DUCKY_REGAL, *DUCKY_TUBE, *DUCKY_HUNT, *DUCKY_WIZARD, *DUCKY_PARTY, *DUCKY_ANGEL, *DUCKY_MAUL, *DUCKY_SANTA]
+    custom_emojis:
+        - *DUCKY_YELLOW
+        - *DUCKY_BLURPLE
+        - *DUCKY_CAMO
+        - *DUCKY_DEVIL
+        - *DUCKY_NINJA
+        - *DUCKY_REGAL
+        - *DUCKY_TUBE
+        - *DUCKY_HUNT
+        - *DUCKY_WIZARD
+        - *DUCKY_PARTY
+        - *DUCKY_ANGEL
+        - *DUCKY_MAUL
+        - *DUCKY_SANTA
 
 config:
     required_keys: ['bot.token']
diff --git a/tests/bot/cogs/sync/test_base.py b/tests/bot/cogs/sync/test_base.py
index e6a6f9688..c2e143865 100644
--- a/tests/bot/cogs/sync/test_base.py
+++ b/tests/bot/cogs/sync/test_base.py
@@ -84,7 +84,7 @@ class SyncerSendPromptTests(unittest.TestCase):
                 mock_()
                 await self.syncer._send_prompt()
 
-                method.assert_called_once_with(constants.Channels.devcore)
+                method.assert_called_once_with(constants.Channels.dev_core)
 
     @helpers.async_test
     async def test_send_prompt_returns_None_if_channel_fetch_fails(self):
@@ -135,7 +135,7 @@ class SyncerConfirmationTests(unittest.TestCase):
     def setUp(self):
         self.bot = helpers.MockBot()
         self.syncer = TestSyncer(self.bot)
-        self.core_dev_role = helpers.MockRole(id=constants.Roles.core_developer)
+        self.core_dev_role = helpers.MockRole(id=constants.Roles.core_developers)
 
     @staticmethod
     def get_message_reaction(emoji):
diff --git a/tests/bot/cogs/test_information.py b/tests/bot/cogs/test_information.py
index deae7ebad..8443cfe71 100644
--- a/tests/bot/cogs/test_information.py
+++ b/tests/bot/cogs/test_information.py
@@ -19,7 +19,7 @@ class InformationCogTests(unittest.TestCase):
 
     @classmethod
     def setUpClass(cls):
-        cls.moderator_role = helpers.MockRole(name="Moderator", id=constants.Roles.moderator)
+        cls.moderator_role = helpers.MockRole(name="Moderator", id=constants.Roles.moderators)
 
     def setUp(self):
         """Sets up fresh objects for each test."""
@@ -521,7 +521,7 @@ class UserCommandTests(unittest.TestCase):
         """A regular user should not be able to use this command outside of bot-commands."""
         constants.MODERATION_ROLES = [self.moderator_role.id]
         constants.STAFF_ROLES = [self.moderator_role.id]
-        constants.Channels.bot = 50
+        constants.Channels.bot_commands = 50
 
         ctx = helpers.MockContext(author=self.author, channel=helpers.MockTextChannel(id=100))
 
@@ -533,7 +533,7 @@ class UserCommandTests(unittest.TestCase):
     def test_regular_user_may_use_command_in_bot_commands_channel(self, create_embed, constants):
         """A regular user should be allowed to use `!user` targeting themselves in bot-commands."""
         constants.STAFF_ROLES = [self.moderator_role.id]
-        constants.Channels.bot = 50
+        constants.Channels.bot_commands = 50
 
         ctx = helpers.MockContext(author=self.author, channel=helpers.MockTextChannel(id=50))
 
@@ -546,7 +546,7 @@ class UserCommandTests(unittest.TestCase):
     def test_regular_user_can_explicitly_target_themselves(self, create_embed, constants):
         """A user should target itself with `!user` when a `user` argument was not provided."""
         constants.STAFF_ROLES = [self.moderator_role.id]
-        constants.Channels.bot = 50
+        constants.Channels.bot_commands = 50
 
         ctx = helpers.MockContext(author=self.author, channel=helpers.MockTextChannel(id=50))
 
@@ -559,7 +559,7 @@ class UserCommandTests(unittest.TestCase):
     def test_staff_members_can_bypass_channel_restriction(self, create_embed, constants):
         """Staff members should be able to bypass the bot-commands channel restriction."""
         constants.STAFF_ROLES = [self.moderator_role.id]
-        constants.Channels.bot = 50
+        constants.Channels.bot_commands = 50
 
         ctx = helpers.MockContext(author=self.moderator, channel=helpers.MockTextChannel(id=200))
 
diff --git a/tests/bot/cogs/test_snekbox.py b/tests/bot/cogs/test_snekbox.py
new file mode 100644
index 000000000..985bc66a1
--- /dev/null
+++ b/tests/bot/cogs/test_snekbox.py
@@ -0,0 +1,368 @@
+import asyncio
+import logging
+import unittest
+from functools import partial
+from unittest.mock import MagicMock, Mock, call, patch
+
+from bot.cogs import snekbox
+from bot.cogs.snekbox import Snekbox
+from bot.constants import URLs
+from tests.helpers import (
+    AsyncContextManagerMock, AsyncMock, MockBot, MockContext, MockMessage, MockReaction, MockUser, async_test
+)
+
+
+class SnekboxTests(unittest.TestCase):
+    def setUp(self):
+        """Add mocked bot and cog to the instance."""
+        self.bot = MockBot()
+
+        self.mocked_post = MagicMock()
+        self.mocked_post.json = AsyncMock()
+        self.bot.http_session.post = MagicMock(return_value=AsyncContextManagerMock(self.mocked_post))
+
+        self.cog = Snekbox(bot=self.bot)
+
+    @async_test
+    async def test_post_eval(self):
+        """Post the eval code to the URLs.snekbox_eval_api endpoint."""
+        self.mocked_post.json.return_value = {'lemon': 'AI'}
+
+        self.assertEqual(await self.cog.post_eval("import random"), {'lemon': 'AI'})
+        self.bot.http_session.post.assert_called_once_with(
+            URLs.snekbox_eval_api,
+            json={"input": "import random"},
+            raise_for_status=True
+        )
+
+    @async_test
+    async def test_upload_output_reject_too_long(self):
+        """Reject output longer than MAX_PASTE_LEN."""
+        result = await self.cog.upload_output("-" * (snekbox.MAX_PASTE_LEN + 1))
+        self.assertEqual(result, "too long to upload")
+
+    @async_test
+    async def test_upload_output(self):
+        """Upload the eval output to the URLs.paste_service.format(key="documents") endpoint."""
+        key = "RainbowDash"
+        self.mocked_post.json.return_value = {"key": key}
+
+        self.assertEqual(
+            await self.cog.upload_output("My awesome output"),
+            URLs.paste_service.format(key=key)
+        )
+        self.bot.http_session.post.assert_called_once_with(
+            URLs.paste_service.format(key="documents"),
+            data="My awesome output",
+            raise_for_status=True
+        )
+
+    @async_test
+    async def test_upload_output_gracefully_fallback_if_exception_during_request(self):
+        """Output upload gracefully fallback if the upload fail."""
+        self.mocked_post.json.side_effect = Exception
+        log = logging.getLogger("bot.cogs.snekbox")
+        with self.assertLogs(logger=log, level='ERROR'):
+            await self.cog.upload_output('My awesome output!')
+
+    @async_test
+    async def test_upload_output_gracefully_fallback_if_no_key_in_response(self):
+        """Output upload gracefully fallback if there is no key entry in the response body."""
+        self.mocked_post.json.return_value = {}
+        self.assertEqual((await self.cog.upload_output('My awesome output!')), None)
+
+    def test_prepare_input(self):
+        cases = (
+            ('print("Hello world!")', 'print("Hello world!")', 'non-formatted'),
+            ('`print("Hello world!")`', 'print("Hello world!")', 'one line code block'),
+            ('```\nprint("Hello world!")```', 'print("Hello world!")', 'multiline code block'),
+            ('```py\nprint("Hello world!")```', 'print("Hello world!")', 'multiline python code block'),
+        )
+        for case, expected, testname in cases:
+            with self.subTest(msg=f'Extract code from {testname}.'):
+                self.assertEqual(self.cog.prepare_input(case), expected)
+
+    def test_get_results_message(self):
+        """Return error and message according to the eval result."""
+        cases = (
+            ('ERROR', None, ('Your eval job has failed', 'ERROR')),
+            ('', 128 + snekbox.SIGKILL, ('Your eval job timed out or ran out of memory', '')),
+            ('', 255, ('Your eval job has failed', 'A fatal NsJail error occurred'))
+        )
+        for stdout, returncode, expected in cases:
+            with self.subTest(stdout=stdout, returncode=returncode, expected=expected):
+                actual = self.cog.get_results_message({'stdout': stdout, 'returncode': returncode})
+                self.assertEqual(actual, expected)
+
+    @patch('bot.cogs.snekbox.Signals', side_effect=ValueError)
+    def test_get_results_message_invalid_signal(self, mock_Signals: Mock):
+        self.assertEqual(
+            self.cog.get_results_message({'stdout': '', 'returncode': 127}),
+            ('Your eval job has completed with return code 127', '')
+        )
+
+    @patch('bot.cogs.snekbox.Signals')
+    def test_get_results_message_valid_signal(self, mock_Signals: Mock):
+        mock_Signals.return_value.name = 'SIGTEST'
+        self.assertEqual(
+            self.cog.get_results_message({'stdout': '', 'returncode': 127}),
+            ('Your eval job has completed with return code 127 (SIGTEST)', '')
+        )
+
+    def test_get_status_emoji(self):
+        """Return emoji according to the eval result."""
+        cases = (
+            (' ', -1, ':warning:'),
+            ('Hello world!', 0, ':white_check_mark:'),
+            ('Invalid beard size', -1, ':x:')
+        )
+        for stdout, returncode, expected in cases:
+            with self.subTest(stdout=stdout, returncode=returncode, expected=expected):
+                actual = self.cog.get_status_emoji({'stdout': stdout, 'returncode': returncode})
+                self.assertEqual(actual, expected)
+
+    @async_test
+    async def test_format_output(self):
+        """Test output formatting."""
+        self.cog.upload_output = AsyncMock(return_value='https://testificate.com/')
+
+        too_many_lines = (
+            '001 | v\n002 | e\n003 | r\n004 | y\n005 | l\n006 | o\n'
+            '007 | n\n008 | g\n009 | b\n010 | e\n011 | a\n... (truncated - too many lines)'
+        )
+        too_long_too_many_lines = (
+            "\n".join(
+                f"{i:03d} | {line}" for i, line in enumerate(['verylongbeard' * 10] * 15, 1)
+            )[:1000] + "\n... (truncated - too long, too many lines)"
+        )
+
+        cases = (
+            ('', ('[No output]', None), 'No output'),
+            ('My awesome output', ('My awesome output', None), 'One line output'),
+            ('<@', ("<@\u200B", None), r'Convert <@ to <@\u200B'),
+            ('<!@', ("<!@\u200B", None), r'Convert <!@ to <!@\u200B'),
+            (
+                '\u202E\u202E\u202E',
+                ('Code block escape attempt detected; will not output result', None),
+                'Detect RIGHT-TO-LEFT OVERRIDE'
+            ),
+            (
+                '\u200B\u200B\u200B',
+                ('Code block escape attempt detected; will not output result', None),
+                'Detect ZERO WIDTH SPACE'
+            ),
+            ('long\nbeard', ('001 | long\n002 | beard', None), 'Two line output'),
+            (
+                'v\ne\nr\ny\nl\no\nn\ng\nb\ne\na\nr\nd',
+                (too_many_lines, 'https://testificate.com/'),
+                '12 lines output'
+            ),
+            (
+                'verylongbeard' * 100,
+                ('verylongbeard' * 76 + 'verylongbear\n... (truncated - too long)', 'https://testificate.com/'),
+                '1300 characters output'
+            ),
+            (
+                ('verylongbeard' * 10 + '\n') * 15,
+                (too_long_too_many_lines, 'https://testificate.com/'),
+                '15 lines, 1965 characters output'
+            ),
+        )
+        for case, expected, testname in cases:
+            with self.subTest(msg=testname, case=case, expected=expected):
+                self.assertEqual(await self.cog.format_output(case), expected)
+
+    @async_test
+    async def test_eval_command_evaluate_once(self):
+        """Test the eval command procedure."""
+        ctx = MockContext()
+        response = MockMessage()
+        self.cog.prepare_input = MagicMock(return_value='MyAwesomeFormattedCode')
+        self.cog.send_eval = AsyncMock(return_value=response)
+        self.cog.continue_eval = AsyncMock(return_value=None)
+
+        await self.cog.eval_command.callback(self.cog, ctx=ctx, code='MyAwesomeCode')
+        self.cog.prepare_input.assert_called_once_with('MyAwesomeCode')
+        self.cog.send_eval.assert_called_once_with(ctx, 'MyAwesomeFormattedCode')
+        self.cog.continue_eval.assert_called_once_with(ctx, response)
+
+    @async_test
+    async def test_eval_command_evaluate_twice(self):
+        """Test the eval and re-eval command procedure."""
+        ctx = MockContext()
+        response = MockMessage()
+        self.cog.prepare_input = MagicMock(return_value='MyAwesomeFormattedCode')
+        self.cog.send_eval = AsyncMock(return_value=response)
+        self.cog.continue_eval = AsyncMock()
+        self.cog.continue_eval.side_effect = ('MyAwesomeCode-2', None)
+
+        await self.cog.eval_command.callback(self.cog, ctx=ctx, code='MyAwesomeCode')
+        self.cog.prepare_input.has_calls(call('MyAwesomeCode'), call('MyAwesomeCode-2'))
+        self.cog.send_eval.assert_called_with(ctx, 'MyAwesomeFormattedCode')
+        self.cog.continue_eval.assert_called_with(ctx, response)
+
+    @async_test
+    async def test_eval_command_reject_two_eval_at_the_same_time(self):
+        """Test if the eval command rejects an eval if the author already have a running eval."""
+        ctx = MockContext()
+        ctx.author.id = 42
+        ctx.author.mention = '@LemonLemonishBeard#0042'
+        ctx.send = AsyncMock()
+        self.cog.jobs = (42,)
+        await self.cog.eval_command.callback(self.cog, ctx=ctx, code='MyAwesomeCode')
+        ctx.send.assert_called_once_with(
+            "@LemonLemonishBeard#0042 You've already got a job running - please wait for it to finish!"
+        )
+
+    @async_test
+    async def test_eval_command_call_help(self):
+        """Test if the eval command call the help command if no code is provided."""
+        ctx = MockContext()
+        ctx.invoke = AsyncMock()
+        await self.cog.eval_command.callback(self.cog, ctx=ctx, code='')
+        ctx.invoke.assert_called_once_with(self.bot.get_command("help"), "eval")
+
+    @async_test
+    async def test_send_eval(self):
+        """Test the send_eval function."""
+        ctx = MockContext()
+        ctx.message = MockMessage()
+        ctx.send = AsyncMock()
+        ctx.author.mention = '@LemonLemonishBeard#0042'
+        ctx.typing = MagicMock(return_value=AsyncContextManagerMock(None))
+        self.cog.post_eval = AsyncMock(return_value={'stdout': '', 'returncode': 0})
+        self.cog.get_results_message = MagicMock(return_value=('Return code 0', ''))
+        self.cog.get_status_emoji = MagicMock(return_value=':yay!:')
+        self.cog.format_output = AsyncMock(return_value=('[No output]', None))
+
+        await self.cog.send_eval(ctx, 'MyAwesomeCode')
+        ctx.send.assert_called_once_with(
+            '@LemonLemonishBeard#0042 :yay!: Return code 0.\n\n```py\n[No output]\n```'
+        )
+        self.cog.post_eval.assert_called_once_with('MyAwesomeCode')
+        self.cog.get_status_emoji.assert_called_once_with({'stdout': '', 'returncode': 0})
+        self.cog.get_results_message.assert_called_once_with({'stdout': '', 'returncode': 0})
+        self.cog.format_output.assert_called_once_with('')
+
+    @async_test
+    async def test_send_eval_with_paste_link(self):
+        """Test the send_eval function with a too long output that generate a paste link."""
+        ctx = MockContext()
+        ctx.message = MockMessage()
+        ctx.send = AsyncMock()
+        ctx.author.mention = '@LemonLemonishBeard#0042'
+        ctx.typing = MagicMock(return_value=AsyncContextManagerMock(None))
+        self.cog.post_eval = AsyncMock(return_value={'stdout': 'Way too long beard', 'returncode': 0})
+        self.cog.get_results_message = MagicMock(return_value=('Return code 0', ''))
+        self.cog.get_status_emoji = MagicMock(return_value=':yay!:')
+        self.cog.format_output = AsyncMock(return_value=('Way too long beard', 'lookatmybeard.com'))
+
+        await self.cog.send_eval(ctx, 'MyAwesomeCode')
+        ctx.send.assert_called_once_with(
+            '@LemonLemonishBeard#0042 :yay!: Return code 0.'
+            '\n\n```py\nWay too long beard\n```\nFull output: lookatmybeard.com'
+        )
+        self.cog.post_eval.assert_called_once_with('MyAwesomeCode')
+        self.cog.get_status_emoji.assert_called_once_with({'stdout': 'Way too long beard', 'returncode': 0})
+        self.cog.get_results_message.assert_called_once_with({'stdout': 'Way too long beard', 'returncode': 0})
+        self.cog.format_output.assert_called_once_with('Way too long beard')
+
+    @async_test
+    async def test_send_eval_with_non_zero_eval(self):
+        """Test the send_eval function with a code returning a non-zero code."""
+        ctx = MockContext()
+        ctx.message = MockMessage()
+        ctx.send = AsyncMock()
+        ctx.author.mention = '@LemonLemonishBeard#0042'
+        ctx.typing = MagicMock(return_value=AsyncContextManagerMock(None))
+        self.cog.post_eval = AsyncMock(return_value={'stdout': 'ERROR', 'returncode': 127})
+        self.cog.get_results_message = MagicMock(return_value=('Return code 127', 'Beard got stuck in the eval'))
+        self.cog.get_status_emoji = MagicMock(return_value=':nope!:')
+        self.cog.format_output = AsyncMock()  # This function isn't called
+
+        await self.cog.send_eval(ctx, 'MyAwesomeCode')
+        ctx.send.assert_called_once_with(
+            '@LemonLemonishBeard#0042 :nope!: Return code 127.\n\n```py\nBeard got stuck in the eval\n```'
+        )
+        self.cog.post_eval.assert_called_once_with('MyAwesomeCode')
+        self.cog.get_status_emoji.assert_called_once_with({'stdout': 'ERROR', 'returncode': 127})
+        self.cog.get_results_message.assert_called_once_with({'stdout': 'ERROR', 'returncode': 127})
+        self.cog.format_output.assert_not_called()
+
+    @async_test
+    async def test_continue_eval_does_continue(self):
+        """Test that the continue_eval function does continue if required conditions are met."""
+        ctx = MockContext(message=MockMessage(add_reaction=AsyncMock(), clear_reactions=AsyncMock()))
+        response = MockMessage(delete=AsyncMock())
+        new_msg = MockMessage(content='!e NewCode')
+        self.bot.wait_for.side_effect = ((None, new_msg), None)
+
+        actual = await self.cog.continue_eval(ctx, response)
+        self.assertEqual(actual, 'NewCode')
+        self.bot.wait_for.has_calls(
+            call('message_edit', partial(snekbox.predicate_eval_message_edit, ctx), timeout=10),
+            call('reaction_add', partial(snekbox.predicate_eval_emoji_reaction, ctx), timeout=10)
+        )
+        ctx.message.add_reaction.assert_called_once_with(snekbox.REEVAL_EMOJI)
+        ctx.message.clear_reactions.assert_called_once()
+        response.delete.assert_called_once()
+
+    @async_test
+    async def test_continue_eval_does_not_continue(self):
+        ctx = MockContext(message=MockMessage(clear_reactions=AsyncMock()))
+        self.bot.wait_for.side_effect = asyncio.TimeoutError
+
+        actual = await self.cog.continue_eval(ctx, MockMessage())
+        self.assertEqual(actual, None)
+        ctx.message.clear_reactions.assert_called_once()
+
+    def test_predicate_eval_message_edit(self):
+        """Test the predicate_eval_message_edit function."""
+        msg0 = MockMessage(id=1, content='abc')
+        msg1 = MockMessage(id=2, content='abcdef')
+        msg2 = MockMessage(id=1, content='abcdef')
+
+        cases = (
+            (msg0, msg0, False, 'same ID, same content'),
+            (msg0, msg1, False, 'different ID, different content'),
+            (msg0, msg2, True, 'same ID, different content')
+        )
+        for ctx_msg, new_msg, expected, testname in cases:
+            with self.subTest(msg=f'Messages with {testname} return {expected}'):
+                ctx = MockContext(message=ctx_msg)
+                actual = snekbox.predicate_eval_message_edit(ctx, ctx_msg, new_msg)
+                self.assertEqual(actual, expected)
+
+    def test_predicate_eval_emoji_reaction(self):
+        """Test the predicate_eval_emoji_reaction function."""
+        valid_reaction = MockReaction(message=MockMessage(id=1))
+        valid_reaction.__str__.return_value = snekbox.REEVAL_EMOJI
+        valid_ctx = MockContext(message=MockMessage(id=1), author=MockUser(id=2))
+        valid_user = MockUser(id=2)
+
+        invalid_reaction_id = MockReaction(message=MockMessage(id=42))
+        invalid_reaction_id.__str__.return_value = snekbox.REEVAL_EMOJI
+        invalid_user_id = MockUser(id=42)
+        invalid_reaction_str = MockReaction(message=MockMessage(id=1))
+        invalid_reaction_str.__str__.return_value = ':longbeard:'
+
+        cases = (
+            (invalid_reaction_id, valid_user, False, 'invalid reaction ID'),
+            (valid_reaction, invalid_user_id, False, 'invalid user ID'),
+            (invalid_reaction_str, valid_user, False, 'invalid reaction __str__'),
+            (valid_reaction, valid_user, True, 'matching attributes')
+        )
+        for reaction, user, expected, testname in cases:
+            with self.subTest(msg=f'Test with {testname} and expected return {expected}'):
+                actual = snekbox.predicate_eval_emoji_reaction(valid_ctx, reaction, user)
+                self.assertEqual(actual, expected)
+
+
+class SnekboxSetupTests(unittest.TestCase):
+    """Tests setup of the `Snekbox` cog."""
+
+    def test_setup(self):
+        """Setup of the extension should call add_cog."""
+        bot = MockBot()
+        snekbox.setup(bot)
+        bot.add_cog.assert_called_once()
diff --git a/tests/bot/test_converters.py b/tests/bot/test_converters.py
index b2b78d9dd..1e5ca62ae 100644
--- a/tests/bot/test_converters.py
+++ b/tests/bot/test_converters.py
@@ -68,7 +68,7 @@ class ConverterTests(unittest.TestCase):
             ('👋', "Don't be ridiculous, you can't use that character!"),
             ('', "Tag names should not be empty, or filled with whitespace."),
             ('  ', "Tag names should not be empty, or filled with whitespace."),
-            ('42', "Tag names can't be numbers."),
+            ('42', "Tag names must contain at least one letter."),
             ('x' * 128, "Are you insane? That's way too long!"),
         )
 
diff --git a/tests/bot/test_utils.py b/tests/bot/test_utils.py
index 58ae2a81a..d7bcc3ba6 100644
--- a/tests/bot/test_utils.py
+++ b/tests/bot/test_utils.py
@@ -35,18 +35,3 @@ class CaseInsensitiveDictTests(unittest.TestCase):
         instance = utils.CaseInsensitiveDict()
         instance.update({'FOO': 'bar'})
         self.assertEqual(instance['foo'], 'bar')
-
-
-class ChunkTests(unittest.TestCase):
-    """Tests the `chunk` method."""
-
-    def test_empty_chunking(self):
-        """Tests chunking on an empty iterable."""
-        generator = utils.chunks(iterable=[], size=5)
-        self.assertEqual(list(generator), [])
-
-    def test_list_chunking(self):
-        """Tests chunking a non-empty list."""
-        iterable = [1, 2, 3, 4, 5]
-        generator = utils.chunks(iterable=iterable, size=2)
-        self.assertEqual(list(generator), [[1, 2], [3, 4], [5]])
diff --git a/tests/helpers.py b/tests/helpers.py
index 9d9dd5da6..6f50f6ae3 100644
--- a/tests/helpers.py
+++ b/tests/helpers.py
@@ -128,6 +128,18 @@ class AsyncMock(CustomMockMixin, unittest.mock.MagicMock):
         return super().__call__(*args, **kwargs)
 
 
+class AsyncContextManagerMock(unittest.mock.MagicMock):
+    def __init__(self, return_value: Any):
+        super().__init__()
+        self._return_value = return_value
+
+    async def __aenter__(self):
+        return self._return_value
+
+    async def __aexit__(self, *args):
+        pass
+
+
 class AsyncIteratorMock:
     """
     A class to mock asynchronous iterators.