Support multi-prefix

See http://ircv3.net/specs/extensions/multi-prefix-3.1.html
ref #3103

src/irc/irc_client.cpp

@@ -151,6 +151,9 @@ void IrcClient::on_connected()
         }
     }
 
+  this->send_message({"CAP", {"REQ", "multi-prefix"}});
+  this->send_message({"CAP", {"END"}});
+
 #ifdef USE_DATABASE
   auto options = Database::get_irc_server_options(this->bridge.get_bare_jid(),
                                                   this->get_hostname());

src/irc/irc_user.cpp

@@ -7,8 +7,20 @@ IrcUser::IrcUser(const std::string& name,
 {
   if (name.empty())
     return ;
-  const std::map<char, char>::const_iterator prefix = prefix_to_mode.find(name[0]);
+
-  const std::string::size_type name_begin = prefix == prefix_to_mode.end()? 0: 1;
+  // One or more prefix (with multi-prefix support) may come before the
+  // actual nick
+  std::string::size_type name_begin = 0;
+  while (name_begin != name.size())
+    {
+      const auto prefix = prefix_to_mode.find(name[name_begin]);
+      // This is not a prefix
+      if (prefix == prefix_to_mode.end())
+        break;
+      this->modes.insert(prefix->second);
+      name_begin++;
+    }
+
   const std::string::size_type sep = name.find("!", name_begin);
   if (sep == std::string::npos)
     this->nick = name.substr(name_begin);
@@ -17,8 +29,6 @@ IrcUser::IrcUser(const std::string& name,
       this->nick = name.substr(name_begin, sep-name_begin);
       this->host = name.substr(sep+1);
     }
-  if (prefix != prefix_to_mode.end())
-    this->modes.insert(prefix->second);
 }
 
 IrcUser::IrcUser(const std::string& name):

tests/iid.cpp

@@ -8,7 +8,6 @@
 TEST_CASE("Irc user parsing")
 {
   const std::map<char, char> prefixes{{'!', 'a'}, {'@', 'o'}};
-
   IrcUser user1("!nick!~some@host.bla", prefixes);
   CHECK(user1.nick == "nick");
   CHECK(user1.host == "~some@host.bla");
@@ -22,6 +21,15 @@ TEST_CASE("Irc user parsing")
   CHECK(user2.modes.find('a') == user2.modes.end());
 }
 
+TEST_CASE("multi-prefix")
+{
+  const std::map<char, char> prefixes{{'!', 'a'}, {'@', 'o'}, {'~', 'f'}};
+  IrcUser user("!@~nick", prefixes);
+  CHECK(user.nick == "nick");
+  CHECK(user.modes.size() == 3);
+  CHECK(user.modes.find('f') != user.modes.end());
+}
+
 /**
  * Let Catch know how to display Iid objects
  */