Merge branch 'master' into redis_persistence

11 files changed, 154 insertions, 80 deletions

diff --git a/bot/cogs/error_handler.py b/bot/cogs/error_handler.py
index 77d16c051..5de961116 100644
--- a/bot/cogs/error_handler.py
+++ b/bot/cogs/error_handler.py
@@ -9,7 +9,7 @@ from bot.api import ResponseCodeError
 from bot.bot import Bot
 from bot.constants import Channels
 from bot.converters import TagNameConverter
-from bot.decorators import InWhitelistCheckFailure
+from bot.utils.checks import InWhitelistCheckFailure
 
 log = logging.getLogger(__name__)
 
diff --git a/bot/cogs/information.py b/bot/cogs/information.py
index ef2f308ca..f0eb3a1ea 100644
--- a/bot/cogs/information.py
+++ b/bot/cogs/information.py
@@ -12,9 +12,9 @@ from discord.utils import escape_markdown
 
 from bot import constants
 from bot.bot import Bot
-from bot.decorators import InWhitelistCheckFailure, in_whitelist, with_role
+from bot.decorators import in_whitelist, with_role
 from bot.pagination import LinePaginator
-from bot.utils.checks import cooldown_with_role_bypass, with_role_check
+from bot.utils.checks import InWhitelistCheckFailure, cooldown_with_role_bypass, with_role_check
 from bot.utils.time import time_since
 
 log = logging.getLogger(__name__)
diff --git a/bot/cogs/moderation/management.py b/bot/cogs/moderation/management.py
index 7af3df463..c39c7f3bc 100644
--- a/bot/cogs/moderation/management.py
+++ b/bot/cogs/moderation/management.py
@@ -12,7 +12,7 @@ from bot.bot import Bot
 from bot.converters import Expiry, InfractionSearchQuery, allowed_strings, proxy_user
 from bot.pagination import LinePaginator
 from bot.utils import time
-from bot.utils.checks import in_channel_check, with_role_check
+from bot.utils.checks import in_whitelist_check, with_role_check
 from . import utils
 from .infractions import Infractions
 from .modlog import ModLog
@@ -283,10 +283,16 @@ class ModManagement(commands.Cog):
 
     # This cannot be static (must have a __func__ attribute).
     def cog_check(self, ctx: Context) -> bool:
-        """Only allow moderators from moderator channels to invoke the commands in this cog."""
+        """Only allow moderators inside moderator channels to invoke the commands in this cog."""
         checks = [
             with_role_check(ctx, *constants.MODERATION_ROLES),
-            in_channel_check(ctx, *constants.MODERATION_CHANNELS)
+            in_whitelist_check(
+                ctx,
+                channels=constants.MODERATION_CHANNELS,
+                categories=[constants.Categories.modmail],
+                redirect=None,
+                fail_silently=True,
+            )
         ]
         return all(checks)
 
diff --git a/bot/cogs/verification.py b/bot/cogs/verification.py
index 77e8b5706..99be3cdaa 100644
--- a/bot/cogs/verification.py
+++ b/bot/cogs/verification.py
@@ -9,8 +9,8 @@ from discord.ext.commands import Cog, Context, command
 from bot import constants
 from bot.bot import Bot
 from bot.cogs.moderation import ModLog
-from bot.decorators import InWhitelistCheckFailure, in_whitelist, without_role
-from bot.utils.checks import without_role_check
+from bot.decorators import in_whitelist, without_role
+from bot.utils.checks import InWhitelistCheckFailure, without_role_check
 
 log = logging.getLogger(__name__)
 
diff --git a/bot/constants.py b/bot/constants.py
index eae083ab4..b31a9c99e 100644
--- a/bot/constants.py
+++ b/bot/constants.py
@@ -623,13 +623,10 @@ PROJECT_ROOT = os.path.abspath(os.path.join(BOT_DIR, os.pardir))
 MODERATION_ROLES = Guild.moderation_roles
 STAFF_ROLES = Guild.staff_roles
 
-# Roles combinations
+# Channel combinations
 STAFF_CHANNELS = Guild.staff_channels
-
-# Default Channel combinations
 MODERATION_CHANNELS = Guild.moderation_channels
 
-
 # Bot replies
 NEGATIVE_REPLIES = [
     "Noooooo!!",
diff --git a/bot/decorators.py b/bot/decorators.py
index 3c904cf7c..500197c89 100644
--- a/bot/decorators.py
+++ b/bot/decorators.py
@@ -9,37 +9,21 @@ from weakref import WeakValueDictionary
 from discord import Colour, Embed, Member
 from discord.errors import NotFound
 from discord.ext import commands
-from discord.ext.commands import CheckFailure, Cog, Context
+from discord.ext.commands import Cog, Context
 
 from bot.constants import Channels, ERROR_REPLIES, RedirectOutput
-from bot.utils.checks import with_role_check, without_role_check
+from bot.utils.checks import in_whitelist_check, with_role_check, without_role_check
 
 log = logging.getLogger(__name__)
 
 
-class InWhitelistCheckFailure(CheckFailure):
-    """Raised when the `in_whitelist` check fails."""
-
-    def __init__(self, redirect_channel: Optional[int]) -> None:
-        self.redirect_channel = redirect_channel
-
-        if redirect_channel:
-            redirect_message = f" here. Please use the <#{redirect_channel}> channel instead"
-        else:
-            redirect_message = ""
-
-        error_message = f"You are not allowed to use that command{redirect_message}."
-
-        super().__init__(error_message)
-
-
 def in_whitelist(
     *,
     channels: Container[int] = (),
     categories: Container[int] = (),
     roles: Container[int] = (),
     redirect: Optional[int] = Channels.bot_commands,
-
+    fail_silently: bool = False,
 ) -> Callable:
     """
     Check if a command was issued in a whitelisted context.
@@ -54,36 +38,9 @@ def in_whitelist(
     redirected to the `redirect` channel that was passed (default: #bot-commands) or simply
     told that they're not allowed to use this particular command (if `None` was passed).
     """
-    if redirect and redirect not in channels:
-        # It does not make sense for the channel whitelist to not contain the redirection
-        # channel (if applicable). That's why we add the redirection channel to the `channels`
-        # container if it's not already in it. As we allow any container type to be passed,
-        # we first create a tuple in order to safely add the redirection channel.
-        #
-        # Note: It's possible for the redirect channel to be in a whitelisted category, but
-        # there's no easy way to check that and as a channel can easily be moved in and out of
-        # categories, it's probably not wise to rely on its category in any case.
-        channels = tuple(channels) + (redirect,)
-
     def predicate(ctx: Context) -> bool:
-        """Check if a command was issued in a whitelisted context."""
-        if channels and ctx.channel.id in channels:
-            log.trace(f"{ctx.author} may use the `{ctx.command.name}` command as they are in a whitelisted channel.")
-            return True
-
-        # Only check the category id if we have a category whitelist and the channel has a `category_id`
-        if categories and hasattr(ctx.channel, "category_id") and ctx.channel.category_id in categories:
-            log.trace(f"{ctx.author} may use the `{ctx.command.name}` command as they are in a whitelisted category.")
-            return True
-
-        # Only check the roles whitelist if we have one and ensure the author's roles attribute returns
-        # an iterable to prevent breakage in DM channels (for if we ever decide to enable commands there).
-        if roles and any(r.id in roles for r in getattr(ctx.author, "roles", ())):
-            log.trace(f"{ctx.author} may use the `{ctx.command.name}` command as they have a whitelisted role.")
-            return True
-
-        log.trace(f"{ctx.author} may not use the `{ctx.command.name}` command within this context.")
-        raise InWhitelistCheckFailure(redirect)
+        """Check if command was issued in a whitelisted context."""
+        return in_whitelist_check(ctx, channels, categories, roles, redirect, fail_silently)
 
     return commands.check(predicate)
 
diff --git a/bot/utils/checks.py b/bot/utils/checks.py
index db56c347c..f0ef36302 100644
--- a/bot/utils/checks.py
+++ b/bot/utils/checks.py
@@ -1,12 +1,94 @@
 import datetime
 import logging
-from typing import Callable, Iterable
+from typing import Callable, Container, Iterable, Optional
 
-from discord.ext.commands import BucketType, Cog, Command, CommandOnCooldown, Context, Cooldown, CooldownMapping
+from discord.ext.commands import (
+    BucketType,
+    CheckFailure,
+    Cog,
+    Command,
+    CommandOnCooldown,
+    Context,
+    Cooldown,
+    CooldownMapping,
+)
+
+from bot import constants
 
 log = logging.getLogger(__name__)
 
 
+class InWhitelistCheckFailure(CheckFailure):
+    """Raised when the `in_whitelist` check fails."""
+
+    def __init__(self, redirect_channel: Optional[int]) -> None:
+        self.redirect_channel = redirect_channel
+
+        if redirect_channel:
+            redirect_message = f" here. Please use the <#{redirect_channel}> channel instead"
+        else:
+            redirect_message = ""
+
+        error_message = f"You are not allowed to use that command{redirect_message}."
+
+        super().__init__(error_message)
+
+
+def in_whitelist_check(
+    ctx: Context,
+    channels: Container[int] = (),
+    categories: Container[int] = (),
+    roles: Container[int] = (),
+    redirect: Optional[int] = constants.Channels.bot_commands,
+    fail_silently: bool = False,
+) -> bool:
+    """
+    Check if a command was issued in a whitelisted context.
+
+    The whitelists that can be provided are:
+
+    - `channels`: a container with channel ids for whitelisted channels
+    - `categories`: a container with category ids for whitelisted categories
+    - `roles`: a container with with role ids for whitelisted roles
+
+    If the command was invoked in a context that was not whitelisted, the member is either
+    redirected to the `redirect` channel that was passed (default: #bot-commands) or simply
+    told that they're not allowed to use this particular command (if `None` was passed).
+    """
+    if redirect and redirect not in channels:
+        # It does not make sense for the channel whitelist to not contain the redirection
+        # channel (if applicable). That's why we add the redirection channel to the `channels`
+        # container if it's not already in it. As we allow any container type to be passed,
+        # we first create a tuple in order to safely add the redirection channel.
+        #
+        # Note: It's possible for the redirect channel to be in a whitelisted category, but
+        # there's no easy way to check that and as a channel can easily be moved in and out of
+        # categories, it's probably not wise to rely on its category in any case.
+        channels = tuple(channels) + (redirect,)
+
+    if channels and ctx.channel.id in channels:
+        log.trace(f"{ctx.author} may use the `{ctx.command.name}` command as they are in a whitelisted channel.")
+        return True
+
+    # Only check the category id if we have a category whitelist and the channel has a `category_id`
+    if categories and hasattr(ctx.channel, "category_id") and ctx.channel.category_id in categories:
+        log.trace(f"{ctx.author} may use the `{ctx.command.name}` command as they are in a whitelisted category.")
+        return True
+
+    # Only check the roles whitelist if we have one and ensure the author's roles attribute returns
+    # an iterable to prevent breakage in DM channels (for if we ever decide to enable commands there).
+    if roles and any(r.id in roles for r in getattr(ctx.author, "roles", ())):
+        log.trace(f"{ctx.author} may use the `{ctx.command.name}` command as they have a whitelisted role.")
+        return True
+
+    log.trace(f"{ctx.author} may not use the `{ctx.command.name}` command within this context.")
+
+    # Some commands are secret, and should produce no feedback at all.
+    if not fail_silently:
+        raise InWhitelistCheckFailure(redirect)
+    return False
+
+
 def with_role_check(ctx: Context, *role_ids: int) -> bool:
     """Returns True if the user has any one of the roles in role_ids."""
     if not ctx.guild:  # Return False in a DM
@@ -38,14 +120,6 @@ def without_role_check(ctx: Context, *role_ids: int) -> bool:
     return check
 
 
-def in_channel_check(ctx: Context, *channel_ids: int) -> bool:
-    """Checks if the command was executed inside the list of specified channels."""
-    check = ctx.channel.id in channel_ids
-    log.trace(f"{ctx.author} tried to call the '{ctx.command.name}' command. "
-              f"The result of the in_channel check was {check}.")
-    return check
-
-
 def cooldown_with_role_bypass(rate: int, per: float, type: BucketType = BucketType.default, *,
                               bypass_roles: Iterable[int]) -> Callable:
     """
diff --git a/config-default.yml b/config-default.yml
index bb66890a3..2c85f5ef3 100644
--- a/config-default.yml
+++ b/config-default.yml
@@ -296,6 +296,7 @@ filter:
         - 81384788765712384   # Discord API
         - 613425648685547541  # Discord Developers
         - 185590609631903755  # Blender Hub
+        - 420324994703163402  # /r/FlutterDev
 
     domain_blacklist:
         - pornhub.com
diff --git a/tests/bot/cogs/test_information.py b/tests/bot/cogs/test_information.py
index b5f928dd6..aca6b594f 100644
--- a/tests/bot/cogs/test_information.py
+++ b/tests/bot/cogs/test_information.py
@@ -7,10 +7,9 @@ import discord
 
 from bot import constants
 from bot.cogs import information
-from bot.decorators import InWhitelistCheckFailure
+from bot.utils.checks import InWhitelistCheckFailure
 from tests import helpers
 
-
 COG_PATH = "bot.cogs.information.Information"
 
 
diff --git a/tests/bot/test_decorators.py b/tests/bot/test_decorators.py
index a17dd3e16..3d450caa0 100644
--- a/tests/bot/test_decorators.py
+++ b/tests/bot/test_decorators.py
@@ -3,10 +3,10 @@ import unittest
 import unittest.mock
 
 from bot import constants
-from bot.decorators import InWhitelistCheckFailure, in_whitelist
+from bot.decorators import in_whitelist
+from bot.utils.checks import InWhitelistCheckFailure
 from tests import helpers
 
-
 InWhitelistTestCase = collections.namedtuple("WhitelistedContextTestCase", ("kwargs", "ctx", "description"))
 
 
diff --git a/tests/bot/utils/test_checks.py b/tests/bot/utils/test_checks.py
index 9610771e5..de72e5748 100644
--- a/tests/bot/utils/test_checks.py
+++ b/tests/bot/utils/test_checks.py
@@ -1,6 +1,8 @@
 import unittest
+from unittest.mock import MagicMock
 
 from bot.utils import checks
+from bot.utils.checks import InWhitelistCheckFailure
 from tests.helpers import MockContext, MockRole
 
 
@@ -42,10 +44,48 @@ class ChecksTests(unittest.TestCase):
         self.ctx.author.roles.append(MockRole(id=role_id))
         self.assertTrue(checks.without_role_check(self.ctx, role_id + 10))
 
-    def test_in_channel_check_for_correct_channel(self):
-        self.ctx.channel.id = 42
-        self.assertTrue(checks.in_channel_check(self.ctx, *[42]))
+    def test_in_whitelist_check_correct_channel(self):
+        """`in_whitelist_check` returns `True` if `Context.channel.id` is in the channel list."""
+        channel_id = 3
+        self.ctx.channel.id = channel_id
+        self.assertTrue(checks.in_whitelist_check(self.ctx, [channel_id]))
 
-    def test_in_channel_check_for_incorrect_channel(self):
-        self.ctx.channel.id = 42 + 10
-        self.assertFalse(checks.in_channel_check(self.ctx, *[42]))
+    def test_in_whitelist_check_incorrect_channel(self):
+        """`in_whitelist_check` raises InWhitelistCheckFailure if there's no channel match."""
+        self.ctx.channel.id = 3
+        with self.assertRaises(InWhitelistCheckFailure):
+            checks.in_whitelist_check(self.ctx, [4])
+
+    def test_in_whitelist_check_correct_category(self):
+        """`in_whitelist_check` returns `True` if `Context.channel.category_id` is in the category list."""
+        category_id = 3
+        self.ctx.channel.category_id = category_id
+        self.assertTrue(checks.in_whitelist_check(self.ctx, categories=[category_id]))
+
+    def test_in_whitelist_check_incorrect_category(self):
+        """`in_whitelist_check` raises InWhitelistCheckFailure if there's no category match."""
+        self.ctx.channel.category_id = 3
+        with self.assertRaises(InWhitelistCheckFailure):
+            checks.in_whitelist_check(self.ctx, categories=[4])
+
+    def test_in_whitelist_check_correct_role(self):
+        """`in_whitelist_check` returns `True` if any of the `Context.author.roles` are in the roles list."""
+        self.ctx.author.roles = (MagicMock(id=1), MagicMock(id=2))
+        self.assertTrue(checks.in_whitelist_check(self.ctx, roles=[2, 6]))
+
+    def test_in_whitelist_check_incorrect_role(self):
+        """`in_whitelist_check` raises InWhitelistCheckFailure if there's no role match."""
+        self.ctx.author.roles = (MagicMock(id=1), MagicMock(id=2))
+        with self.assertRaises(InWhitelistCheckFailure):
+            checks.in_whitelist_check(self.ctx, roles=[4])
+
+    def test_in_whitelist_check_fail_silently(self):
+        """`in_whitelist_check` test no exception raised if `fail_silently` is `True`"""
+        self.assertFalse(checks.in_whitelist_check(self.ctx, roles=[2, 6], fail_silently=True))
+
+    def test_in_whitelist_check_complex(self):
+        """`in_whitelist_check` test with multiple parameters"""
+        self.ctx.author.roles = (MagicMock(id=1), MagicMock(id=2))
+        self.ctx.channel.category_id = 3
+        self.ctx.channel.id = 5
+        self.assertTrue(checks.in_whitelist_check(self.ctx, channels=[1], categories=[8], roles=[2]))