Properly handle force-join presences by sending everything in return

fix #3305

src/bridge/bridge.cpp

@@ -166,8 +166,11 @@ IrcClient* Bridge::find_irc_client(const std::string& hostname) const
     }
 }
 
-bool Bridge::join_irc_channel(const Iid& iid, std::string nickname, const std::string& password,
+bool Bridge::join_irc_channel(const Iid& iid, std::string nickname,
-                              const std::string& resource, HistoryLimit history_limit)
+                              const std::string& password,
+                              const std::string& resource,
+                              HistoryLimit history_limit,
+                              const bool force_join)
 {
   const auto& hostname = iid.get_server();
 #ifdef USE_DATABASE
@@ -185,7 +188,8 @@ bool Bridge::join_irc_channel(const Iid& iid, std::string nickname, const std::s
     {
       irc->send_join_command(iid.get_local(), password);
       return true;
-    } else if (!res_in_chan) {
+    } else if (!res_in_chan || force_join) {
+      // See https://github.com/xsf/xeps/pull/499 for the force_join argument
       this->generate_channel_join_for_resource(iid, resource);
     }
   return false;

src/bridge/bridge.hpp

@@ -75,7 +75,11 @@ public:
    * Try to join an irc_channel, does nothing and return true if the channel
    * was already joined.
    */
-  bool join_irc_channel(const Iid& iid, std::string nickname, const std::string& password, const std::string& resource, HistoryLimit history_limit);
+  bool join_irc_channel(const Iid& iid, std::string nickname,
+                        const std::string& password,
+                        const std::string& resource,
+                        HistoryLimit history_limit,
+                        const bool force_join);
 
   void send_channel_message(const Iid& iid, const std::string& body, std::string id);
   void send_private_message(const Iid& iid, const std::string& body, const std::string& type="PRIVMSG");

src/xmpp/biboumi_component.cpp

@@ -181,7 +181,7 @@ void BiboumiComponent::handle_presence(const Stanza& stanza)
                 history_limit.stanzas = 0;
             }
           bridge->join_irc_channel(iid, to.resource, password ? password->get_inner(): "",
-                                   from.resource, history_limit);
+                                   from.resource, history_limit, x != nullptr);
         }
       else if (type == "unavailable")
         {

tests/end_to_end/__main__.py

@@ -706,6 +706,47 @@ if __name__ == '__main__':
                          ("/message[@from='#foo%{irc_server_one}'][@type='groupchat']/subject[not(text())]",),
                          ]),
                  ]),
+        Scenario("channel_force_join",
+                 [
+                     handshake_sequence(),
+                     # First user joins
+                     partial(send_stanza,
+                             "<presence from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}/{nick_one}'><x xmlns='http://jabber.org/protocol/muc'/></presence>"),
+                     connection_sequence("irc.localhost", '{jid_one}/{resource_one}'),
+                     partial(expect_stanza,
+                             "/message/body[text()='Mode #foo [+nt] by {irc_host_one}']"),
+                     partial(expect_stanza,
+                             ("/presence[@to='{jid_one}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_one}']/muc_user:x/muc_user:item[@affiliation='admin'][@jid='~nick@localhost'][@role='moderator']",
+                             "/presence/muc_user:x/muc_user:status[@code='110']")
+                             ),
+                     partial(expect_stanza, "/message[@from='#foo%{irc_server_one}'][@type='groupchat']/subject[not(text())]"),
+
+                     # Second user joins
+                     partial(send_stanza,
+                             "<presence from='{jid_two}/{resource_one}' to='#foo%{irc_server_one}/{nick_two}'><x xmlns='http://jabber.org/protocol/muc'/></presence>"),
+                     connection_sequence("irc.localhost", '{jid_two}/{resource_one}'),
+                     partial(expect_unordered, [
+                         ("/presence[@to='{jid_one}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_two}']/muc_user:x/muc_user:item[@affiliation='none'][@role='participant'][@jid='~bobby@localhost']",),
+                         ("/presence[@to='{jid_two}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_one}']/muc_user:x/muc_user:item[@affiliation='admin'][@role='moderator']",),
+                         ("/presence[@to='{jid_two}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_two}']/muc_user:x/muc_user:item[@affiliation='none'][@jid='~bobby@localhost'][@role='participant']",
+                         "/presence/muc_user:x/muc_user:status[@code='110']",),
+                         ("/message[@from='#foo%{irc_server_one}'][@type='groupchat']/subject[not(text())]",),
+                         ]),
+
+                     # Here we simulate a desynchronization of a client: The client thinks it’s
+                     # disconnected from the room, but biboumi still thinks it’s in the room. The
+                     # client thus sends a join presence, and biboumi should send everything
+                     # (user list, history, etc) in response
+                     partial(send_stanza,
+                             "<presence from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}/{nick_one}'><x xmlns='http://jabber.org/protocol/muc'/></presence>"),
+
+                     partial(expect_unordered, [
+                         ("/presence[@to='{jid_one}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_two}']/muc_user:x/muc_user:item[@affiliation='none'][@role='participant'][@jid='~bobby@localhost']",),
+                         ("/presence[@to='{jid_one}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_one}']/muc_user:x/muc_user:item[@affiliation='admin'][@role='moderator']",
+                          "/presence/muc_user:x/muc_user:status[@code='110']",),
+                         ("/message[@from='#foo%{irc_server_one}'][@type='groupchat']/subject[not(text())]",),
+                         ]),
+                 ]),
         Scenario("channel_join_with_password",
                  [
                      handshake_sequence(),