From bbc2e9de0d99102ba5ce20fb4f54a697beb7cda8 Mon Sep 17 00:00:00 2001
From: Valentin Lorentz <progval+git@progval.net>
Date: Sat, 13 Mar 2021 19:00:41 +0100
Subject: [PATCH] irclib: 'lift' message tags to the batch when sending a
 multiline batch

---
 src/callbacks.py       | 18 +++++++++++++---
 test/test_callbacks.py | 49 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/src/callbacks.py b/src/callbacks.py
index b7128750b..1326d1a0a 100644
--- a/src/callbacks.py
+++ b/src/callbacks.py
@@ -1114,19 +1114,31 @@ class NestedCommandsIrcProxy(ReplyIrcProxy):
         # It's not optimal, but close enough and simplifies the code.
         messages_per_batch = max_bytes_per_batch // allowedLength
 
+        # "Clients MUST NOT send tags other than draft/multiline-concat and
+        # batch on messages within the batch. In particular, all client-only
+        # tags associated with the message must be sent attached to the initial
+        # BATCH command."
+        # -- <https://ircv3.net/specs/extensions/multiline>
+        # So we copy the tags of the first message, discard the tags of all
+        # other messages, and apply the tags to the opening BATCH
+        server_tags = msgs[0].server_tags
+
         for batch_msgs in utils.iter.grouper(msgs, messages_per_batch):
             # TODO: should use sendBatch instead of queueBatch if
             # sendImmediately is True
             batch_name = ircutils.makeLabel()
             batch = []
-            batch.append(ircmsgs.IrcMsg(command='BATCH', args=(
-                '+' + batch_name, 'draft/multiline', target)))
+            batch.append(ircmsgs.IrcMsg(command='BATCH',
+                args=('+' + batch_name, 'draft/multiline', target),
+                server_tags=server_tags))
 
             for (i, batch_msg) in enumerate(batch_msgs):
                 if batch_msg is None:
                     continue  # 'grouper' generates None at the end
                 assert 'batch' not in batch_msg.server_tags
-                batch_msg.server_tags['batch'] = batch_name
+
+                # Discard the existing tags, and add the batch ones.
+                batch_msg.server_tags = {'batch': batch_name}
                 if concat and i > 0:
                     # Tell clients not to add a newline after this
                     batch_msg.server_tags['draft/multiline-concat'] = None
diff --git a/test/test_callbacks.py b/test/test_callbacks.py
index bfb1d0e15..7d1c9239a 100644
--- a/test/test_callbacks.py
+++ b/test/test_callbacks.py
@@ -699,9 +699,15 @@ class MultilinePrivmsgTestCase(ChannelPluginTestCase):
 
     def setUp(self):
         super().setUp()
+
+        # Enable multiline
         self.irc.state.capabilities_ack.add('batch')
         self.irc.state.capabilities_ack.add('draft/multiline')
         self.irc.state.capabilities_ls['draft/multiline'] = 'max-bytes=4096'
+
+        # Enable msgid and +draft/reply
+        self.irc.state.capabilities_ack.add('message-tags')
+
         conf.supybot.protocols.irc.experimentalExtensions.setValue(True)
 
     def tearDown(self):
@@ -871,6 +877,49 @@ class MultilinePrivmsgTestCase(ChannelPluginTestCase):
             m, ircmsgs.IrcMsg(command='BATCH', args=(
                 '-' + batch_name,)))
 
+    def testReplyInstantBatchTags(self):
+        """check a message's tags are 'lifted' to the initial BATCH
+        command."""
+        self.assertIsNone(self.irc.takeMsg())
+
+        conf.supybot.reply.mores.instant.setValue(2)
+        m = ircmsgs.privmsg(
+            self.channel, "@eval 'foo '*300", prefix=self.prefix)
+        m.server_tags['msgid'] = 'initialmsgid'
+        self.irc.feedMsg(m)
+
+        # First message opens the batch
+        m = self.irc.takeMsg()
+        self.assertEqual(m.command, 'BATCH', m)
+        batch_name = m.args[0][1:]
+        self.assertEqual(
+            m, ircmsgs.IrcMsg(command='BATCH',
+                args=('+' + batch_name,
+                    'draft/multiline', self.channel),
+                server_tags={'+draft/reply': 'initialmsgid'}))
+
+        # Second message, first PRIVMSG
+        m = self.irc.takeMsg()
+        self.assertEqual(
+            m, ircmsgs.IrcMsg(command='PRIVMSG',
+                args=(self.channel, "test: '" + "foo " * 110),
+                server_tags={'batch': batch_name}))
+
+        # Third message, last PRIVMSG
+        m = self.irc.takeMsg()
+        self.assertEqual(
+            m, ircmsgs.IrcMsg(command='PRIVMSG',
+                args=(self.channel,
+                    "test: " + "foo " * 111 + "\x02(1 more message)\x02"),
+                server_tags={'batch': batch_name,
+                    'draft/multiline-concat': None}))
+
+        # Last message, closes the batch
+        m = self.irc.takeMsg()
+        self.assertEqual(
+            m, ircmsgs.IrcMsg(command='BATCH', args=(
+                '-' + batch_name,)))
+
 
 class PluginRegexpTestCase(PluginTestCase):
     plugins = ()