1 files changed, 93 insertions, 0 deletions
diff --git a/tests/bot/rules/test_links.py b/tests/bot/rules/test_links.py
new file mode 100644
index 000000000..f71a8e6bb
--- /dev/null
+++ b/tests/bot/rules/test_links.py
@@ -0,0 +1,93 @@
+import unittest
+from typing import List, NamedTuple, Tuple
+
+from bot.rules import links
+from tests.helpers import async_test
+
+
+class FakeMessage(NamedTuple):
+    author: str
+    content: str
+
+
+class Case(NamedTuple):
+    recent_messages: List[FakeMessage]
+    relevant_messages: Tuple[FakeMessage]
+    culprit: Tuple[str]
+    total_links: int
+
+
+def msg(author: str, total_links: int) -> FakeMessage:
+    """Makes a message with `total_links` links."""
+    content = " ".join(["https://pydis.com"] * total_links)
+    return FakeMessage(author=author, content=content)
+
+
+class LinksTests(unittest.TestCase):
+    """Tests applying the `links` rule."""
+
+    def setUp(self):
+        self.config = {
+            "max": 2,
+            "interval": 10
+        }
+
+    @async_test
+    async def test_links_within_limit(self):
+        """Messages with an allowed amount of links."""
+        cases = (
+            [msg("bob", 0)],
+            [msg("bob", 2)],
+            [msg("bob", 3)],
+            [msg("bob", 3), msg("alice", 3)]
+        )
+
+        for recent_messages in cases:
+            last_message = recent_messages[0]
+            with self.subTest(
+                last_message=last_message,
+                recent_messages=recent_messages,
+                config=self.config
+            ):
+                self.assertIsNone(
+                    await links.apply(last_message, recent_messages, self.config)
+                )
+
+    @async_test
+    async def test_links_exceeding_limit(self):
+        """Messages with a a higher than allowed amount of links."""
+        cases = (
+            Case(
+                [msg("bob", 1), msg("bob", 2)],
+                (msg("bob", 1), msg("bob", 2)),
+                ("bob",),
+                3
+            ),
+            Case(
+                [msg("alice", 2), msg("bob", 3), msg("alice", 1)],
+                (msg("alice", 2), msg("alice", 1)),
+                ("alice",),
+                3
+            )
+        )
+
+        for recent_messages, relevant_messages, culprit, total_links in cases:
+            last_message = recent_messages[0]
+
+            with self.subTest(
+                last_message=last_message,
+                recent_messages=recent_messages,
+                relevant_messages=relevant_messages,
+                culprit=culprit,
+                total_links=total_links,
+                config=self.config
+            ):
+                desired_output = (
+                    f"sent {total_links} links in {self.config['interval']}s",
+                    culprit,
+                    relevant_messages
+                )
+                self.assertTupleEqual(
+                    await links.apply(last_message, recent_messages, self.config),
+                    desired_output
+                )