Make Message.link Point to Thread View Where Possible (#3640)

telegram/_message.py

@@ -826,11 +826,20 @@ class Message(TelegramObject):
     def link(self) -> Optional[str]:
         """:obj:`str`: Convenience property. If the chat of the message is not
         a private chat or normal group, returns a t.me link of the message.
+
+            .. versionchanged:: NEXT.VERSION
+                For messages that are replies or part of a forum topic, the link now points
+                to the corresponding thread view.
         """
         if self.chat.type not in [Chat.PRIVATE, Chat.GROUP]:
             # the else block gets rid of leading -100 for supergroups:
             to_link = self.chat.username if self.chat.username else f"c/{str(self.chat.id)[4:]}"
-            return f"https://t.me/{to_link}/{self.message_id}"
+            baselink = f"https://t.me/{to_link}/{self.message_id}"
+
+            # adds the thread for topics and replies
+            if (self.is_topic_message and self.message_thread_id) or self.reply_to_message:
+                baselink = f"{baselink}?thread={self.message_thread_id}"
+            return baselink
         return None
 
     @classmethod

tests/test_message.py

@@ -791,6 +791,20 @@ class TestMessageWithoutRequest(TestMessageBase):
         # The leading - for group ids/ -100 for supergroup ids isn't supposed to be in the link
         assert message.link == f"https://t.me/c/{3}/{message.message_id}"
 
+    def test_link_with_topics(self, message):
+        message.chat.username = None
+        message.chat.id = -1003
+        message.is_topic_message = True
+        message.message_thread_id = 123
+        assert message.link == f"https://t.me/c/3/{message.message_id}?thread=123"
+
+    def test_link_with_reply(self, message):
+        message.chat.username = None
+        message.chat.id = -1003
+        message.reply_to_message = Message(7, self.from_user, self.date, self.chat, text="Reply")
+        message.message_thread_id = 123
+        assert message.link == f"https://t.me/c/3/{message.message_id}?thread=123"
+
     @pytest.mark.parametrize(("id_", "username"), argvalues=[(None, "username"), (-3, None)])
     def test_link_private_chats(self, message, id_, username):
         message.chat.type = Chat.PRIVATE