1 files changed, 159 insertions, 0 deletions
diff --git a/tests/bot/cogs/test_antimalware.py b/tests/bot/cogs/test_antimalware.py
new file mode 100644
index 000000000..f219fc1ba
--- /dev/null
+++ b/tests/bot/cogs/test_antimalware.py
@@ -0,0 +1,159 @@
+import unittest
+from unittest.mock import AsyncMock, Mock, patch
+
+from discord import NotFound
+
+from bot.cogs import antimalware
+from bot.constants import AntiMalware as AntiMalwareConfig, Channels, STAFF_ROLES
+from tests.helpers import MockAttachment, MockBot, MockMessage, MockRole
+
+MODULE = "bot.cogs.antimalware"
+
+
+@patch(f"{MODULE}.AntiMalwareConfig.whitelist", new=[".first", ".second", ".third"])
+class AntiMalwareCogTests(unittest.IsolatedAsyncioTestCase):
+    """Test the AntiMalware cog."""
+
+    def setUp(self):
+        """Sets up fresh objects for each test."""
+        self.bot = MockBot()
+        self.cog = antimalware.AntiMalware(self.bot)
+        self.message = MockMessage()
+
+    async def test_message_with_allowed_attachment(self):
+        """Messages with allowed extensions should not be deleted"""
+        attachment = MockAttachment(filename=f"python{AntiMalwareConfig.whitelist[0]}")
+        self.message.attachments = [attachment]
+
+        await self.cog.on_message(self.message)
+        self.message.delete.assert_not_called()
+
+    async def test_message_without_attachment(self):
+        """Messages without attachments should result in no action."""
+        await self.cog.on_message(self.message)
+        self.message.delete.assert_not_called()
+
+    async def test_direct_message_with_attachment(self):
+        """Direct messages should have no action taken."""
+        attachment = MockAttachment(filename="python.disallowed")
+        self.message.attachments = [attachment]
+        self.message.guild = None
+
+        await self.cog.on_message(self.message)
+
+        self.message.delete.assert_not_called()
+
+    async def test_message_with_illegal_extension_gets_deleted(self):
+        """A message containing an illegal extension should send an embed."""
+        attachment = MockAttachment(filename="python.disallowed")
+        self.message.attachments = [attachment]
+
+        await self.cog.on_message(self.message)
+
+        self.message.delete.assert_called_once()
+
+    async def test_message_send_by_staff(self):
+        """A message send by a member of staff should be ignored."""
+        staff_role = MockRole(id=STAFF_ROLES[0])
+        self.message.author.roles.append(staff_role)
+        attachment = MockAttachment(filename="python.disallowed")
+        self.message.attachments = [attachment]
+
+        await self.cog.on_message(self.message)
+
+        self.message.delete.assert_not_called()
+
+    async def test_python_file_redirect_embed_description(self):
+        """A message containing a .py file should result in an embed redirecting the user to our paste site"""
+        attachment = MockAttachment(filename="python.py")
+        self.message.attachments = [attachment]
+        self.message.channel.send = AsyncMock()
+
+        await self.cog.on_message(self.message)
+        self.message.channel.send.assert_called_once()
+        args, kwargs = self.message.channel.send.call_args
+        embed = kwargs.pop("embed")
+
+        self.assertEqual(embed.description, antimalware.PY_EMBED_DESCRIPTION)
+
+    async def test_txt_file_redirect_embed_description(self):
+        """A message containing a .txt file should result in the correct embed."""
+        attachment = MockAttachment(filename="python.txt")
+        self.message.attachments = [attachment]
+        self.message.channel.send = AsyncMock()
+        antimalware.TXT_EMBED_DESCRIPTION = Mock()
+        antimalware.TXT_EMBED_DESCRIPTION.format.return_value = "test"
+
+        await self.cog.on_message(self.message)
+        self.message.channel.send.assert_called_once()
+        args, kwargs = self.message.channel.send.call_args
+        embed = kwargs.pop("embed")
+        cmd_channel = self.bot.get_channel(Channels.bot_commands)
+
+        self.assertEqual(embed.description, antimalware.TXT_EMBED_DESCRIPTION.format.return_value)
+        antimalware.TXT_EMBED_DESCRIPTION.format.assert_called_with(cmd_channel_mention=cmd_channel.mention)
+
+    async def test_other_disallowed_extention_embed_description(self):
+        """Test the description for a non .py/.txt disallowed extension."""
+        attachment = MockAttachment(filename="python.disallowed")
+        self.message.attachments = [attachment]
+        self.message.channel.send = AsyncMock()
+        antimalware.DISALLOWED_EMBED_DESCRIPTION = Mock()
+        antimalware.DISALLOWED_EMBED_DESCRIPTION.format.return_value = "test"
+
+        await self.cog.on_message(self.message)
+        self.message.channel.send.assert_called_once()
+        args, kwargs = self.message.channel.send.call_args
+        embed = kwargs.pop("embed")
+        meta_channel = self.bot.get_channel(Channels.meta)
+
+        self.assertEqual(embed.description, antimalware.DISALLOWED_EMBED_DESCRIPTION.format.return_value)
+        antimalware.DISALLOWED_EMBED_DESCRIPTION.format.assert_called_with(
+            blocked_extensions_str=".disallowed",
+            meta_channel_mention=meta_channel.mention
+        )
+
+    async def test_removing_deleted_message_logs(self):
+        """Removing an already deleted message logs the correct message"""
+        attachment = MockAttachment(filename="python.disallowed")
+        self.message.attachments = [attachment]
+        self.message.delete = AsyncMock(side_effect=NotFound(response=Mock(status=""), message=""))
+
+        with self.assertLogs(logger=antimalware.log, level="INFO"):
+            await self.cog.on_message(self.message)
+        self.message.delete.assert_called_once()
+
+    async def test_message_with_illegal_attachment_logs(self):
+        """Deleting a message with an illegal attachment should result in a log."""
+        attachment = MockAttachment(filename="python.disallowed")
+        self.message.attachments = [attachment]
+
+        with self.assertLogs(logger=antimalware.log, level="INFO"):
+            await self.cog.on_message(self.message)
+
+    async def test_get_disallowed_extensions(self):
+        """The return value should include all non-whitelisted extensions."""
+        test_values = (
+            ([], []),
+            (AntiMalwareConfig.whitelist, []),
+            ([".first"], []),
+            ([".first", ".disallowed"], [".disallowed"]),
+            ([".disallowed"], [".disallowed"]),
+            ([".disallowed", ".illegal"], [".disallowed", ".illegal"]),
+        )
+
+        for extensions, expected_disallowed_extensions in test_values:
+            with self.subTest(extensions=extensions, expected_disallowed_extensions=expected_disallowed_extensions):
+                self.message.attachments = [MockAttachment(filename=f"filename{extension}") for extension in extensions]
+                disallowed_extensions = self.cog.get_disallowed_extensions(self.message)
+                self.assertCountEqual(disallowed_extensions, expected_disallowed_extensions)
+
+
+class AntiMalwareSetupTests(unittest.TestCase):
+    """Tests setup of the `AntiMalware` cog."""
+
+    def test_setup(self):
+        """Setup of the extension should call add_cog."""
+        bot = MockBot()
+        antimalware.setup(bot)
+        bot.add_cog.assert_called_once()