Provide stub MODE replies

Clients often expect MODE to be implemented

Author: progval

lib/irc/handler.ex

@@ -1128,6 +1128,43 @@ defmodule M51.IrcConn.Handler do
             close_connection(sup_pid)
         end
 
+      {"MODE", [target]} ->
+        # TODO: check channel exists, and return the appropriate error if it does not
+        case target do
+          << ?#, _::binary >> ->
+            # RPL_CHANNELMODEIS
+            send_numeric.("324", [target, "+nt"])
+          << ?!, _::binary >> ->
+            # RPL_CHANNELMODEIS
+            send_numeric.("324", [target, "+nt"])
+          ^nick ->
+            # RPL_UMODEIS
+            send_numeric.("221", ["+i"])
+          _ ->
+            # ERR_USERSDONTMATCH
+            send_numeric.("502", ["Can't view mode of other users"])
+        end
+
+      {"MODE", [target, _modestring | _]} ->
+        case target do
+          << ?#, _::binary >> ->
+            # ERR_CHANOPRIVSNEEDED
+            send_numeric.("482", [target, "You're not a channel operator"])
+          << ?!, _ ::binary>> ->
+            # ERR_CHANOPRIVSNEEDED
+            send_numeric.("482", [target, "You're not a channel operator"])
+          ^nick ->
+            # ERR_UMODEUNKNOWNFLAG (kind of abusing the meaning, but it's the best I
+            # could find)
+            send_numeric.("501", ["Setting user modes are not supported"])
+          _ ->
+            # ERR_USERSDONTMATCH
+            send_numeric.("502", ["Can't set mode of other users"])
+        end
+
+      {"MODE", []} ->
+        send_needmoreparams.()
+
       {"BATCH", _} ->
         send_needmoreparams.()
 

test/irc/handler_test.exs

@@ -826,6 +826,62 @@ defmodule M51.IrcConn.HandlerTest do
     assert_line("BATCH :-#{batch_id}\r\n")
   end
 
+  test "MODE on user", %{handler: handler} do
+    do_connection_registration(handler)
+
+    send(handler, cmd("@label=l1 MODE unknown_user:example.com"))
+
+    assert_line(
+      "@label=l1 :server. 502 foo:example.org :Can't view mode of other users\r\n"
+    )
+
+    send(handler, cmd("@label=l2 MODE foo:example.org"))
+
+    assert_line(
+      "@label=l2 :server. 221 foo:example.org :+i\r\n"
+    )
+
+    send(handler, cmd("@label=l3 MODE unknown_user:example.com +i"))
+
+    assert_line(
+      "@label=l3 :server. 502 foo:example.org :Can't set mode of other users\r\n"
+    )
+
+    send(handler, cmd("@label=l4 MODE foo:example.org +i"))
+
+    assert_line(
+      "@label=l4 :server. 501 foo:example.org :Setting user modes are not supported\r\n"
+    )
+  end
+
+  test "MODE on channel", %{handler: handler} do
+    do_connection_registration(handler)
+
+    send(handler, cmd("@label=l1 MODE #unknown_channel:example.com"))
+
+    assert_line(
+      "@label=l1 :server. 324 foo:example.org #unknown_channel:example.com :+nt\r\n"
+    )
+
+    send(handler, cmd("@label=l2 MODE !unknown_channel:example.com"))
+
+    assert_line(
+      "@label=l2 :server. 324 foo:example.org !unknown_channel:example.com :+nt\r\n"
+    )
+
+    send(handler, cmd("@label=l3 MODE #unknown_channel:example.com +i"))
+
+    assert_line(
+      "@label=l3 :server. 482 foo:example.org #unknown_channel:example.com :You're not a channel operator\r\n"
+    )
+
+    send(handler, cmd("@label=l4 MODE !unknown_channel:example.com +i"))
+
+    assert_line(
+      "@label=l4 :server. 482 foo:example.org !unknown_channel:example.com :You're not a channel operator\r\n"
+    )
+  end
+
   test "CHATHISTORY AROUND", %{handler: handler} do
     do_connection_registration(handler, ["message-tags"])