Fix missing group members on 2.5 clients

tests/ProtocolCryptoSelfTest.java

@@ -1,4 +1,5 @@
 import de.maxhenkel.voicechat.voice.common.Secret;
+import de.maxhenkel.voicechat.net.ProtocolChannelCompatibility;
 import java.nio.ByteBuffer;
 import java.security.SecureRandom;
 import java.util.Arrays;
@@ -9,6 +10,8 @@ import javax.crypto.spec.SecretKeySpec;
 
 public class ProtocolCryptoSelfTest {
     public static void main(String[] args) throws Exception {
+        testStateChannelCompatibility();
+
         byte[] key = new byte[16];
         for (int i = 0; i < key.length; i++) key[i] = (byte) (i * 13 + 7);
         UUID legacyKey = uuidFromBytes(key);
@@ -34,7 +37,23 @@ public class ProtocolCryptoSelfTest {
                 throw new AssertionError("Hybrid server AES-GCM round-trip failed");
             }
         }
-        System.out.println("PASS: 100 CBC client/server interop cycles and 100 GCM round-trips");
+        System.out.println("PASS: legacy state-channel mapping, 100 CBC interop cycles and 100 GCM round-trips");
+    }
+
+    private static void testStateChannelCompatibility() {
+        check("voicechat:player_state", ProtocolChannelCompatibility.outgoingChannel("voicechat:state", 18));
+        check("voicechat:player_states", ProtocolChannelCompatibility.outgoingChannel("voicechat:states", 18));
+        if (ProtocolChannelCompatibility.outgoingChannel("voicechat:remove_state", 18) != null) {
+            throw new AssertionError("The 2.5 client has no remove-state packet");
+        }
+        check("voicechat:state", ProtocolChannelCompatibility.outgoingChannel("voicechat:state", 20));
+        check("voicechat:states", ProtocolChannelCompatibility.outgoingChannel("voicechat:states", 20));
+    }
+
+    private static void check(String expected, String actual) {
+        if (!expected.equals(actual)) {
+            throw new AssertionError("Expected channel " + expected + ", got " + actual);
+        }
     }
 
     private static UUID uuidFromBytes(byte[] bytes) {