plugins.rules: ignore messages tagged as coming from a bot

Only PRIVMSG and NOTICE messages from bots are filtered out, so this
change doesn't affect Sopel's user tracking. JOINs, PARTs, etc. can be
included later, once there exists a decorator that event handlers can
use to turn this `bot` filter off.

Currently supports the `draft/bot` tag AND the `bot` tag that will be
used when the relevant IRCv3 extension leaves draft status.

It seems like the future-proofing is of minimal risk here.

sopel/plugins/rules.py

@@ -959,6 +959,13 @@ def match_preconditions(self, bot, pretrigger):
         event = pretrigger.event
         intent = pretrigger.tags.get('intent')
         nick = pretrigger.nick
+        is_bot_message = (
+            (
+                'draft/bot' in pretrigger.tags or  # can be removed...someday
+                'bot' in pretrigger.tags
+            ) and
+            event in ["PRIVMSG", "NOTICE"]
+        )
         is_echo_message = (
             nick.lower() == bot.nick.lower() and
             event in ["PRIVMSG", "NOTICE"]
@@ -967,6 +974,7 @@ def match_preconditions(self, bot, pretrigger):
         return (
             self.match_event(event) and
             self.match_intent(intent) and
+            (not is_bot_message or (is_echo_message and self.allow_echo())) and
             (not is_echo_message or self.allow_echo())
         )
 

test/plugins/test_plugins_rules.py

@@ -654,6 +654,23 @@ def test_rule_match_privmsg_action(mockbot):
     assert not list(rule.match(mockbot, pretrigger))
 
 
+def test_rule_match_privmsg_bot_tag(mockbot):
+    regex = re.compile(r'.*')
+    rule = rules.Rule([regex])
+
+    line = '@draft/bot :TestBot!sopel@example.com PRIVMSG #sopel :Hi!'
+    pretrigger = trigger.PreTrigger(mockbot.nick, line)
+    assert not list(rule.match(mockbot, pretrigger)), (
+        'Line with `draft/bot` tag must be ignored'
+    )
+
+    line = '@bot :TestBot!sopel@example.com PRIVMSG #sopel :Hi!'
+    pretrigger = trigger.PreTrigger(mockbot.nick, line)
+    assert not list(rule.match(mockbot, pretrigger)), (
+        'Line with final/ratified `bot` tag must be ignored'
+    )
+
+
 def test_rule_match_privmsg_echo(mockbot):
     line = ':TestBot!sopel@example.com PRIVMSG #sopel :Hi!'
     pretrigger = trigger.PreTrigger(mockbot.nick, line)