Add support for CHGHOST

CHANGELOG

  * Added support for batches
    * All events in a batch are buffered until the batch is finished
    * The events are then published together in a single `BatchReceived` event
+ * Added support for CHGHOST messages
  * (Internal) Introduced event mutators
    * Event mutators are now responsible for handling changing events in response to state
      e.g. ChannelFanOutMutator creates Channel* events for global quits/nick changes/etc

src/main/kotlin/com/dmdirc/ktirc/events/Events.kt

 /** Raised when a user changes nickname. */
 class UserNickChanged(metadata: EventMetadata, val user: User, val newNick: String) : IrcEvent(metadata)
 
+/** Raised when a user changes hostname. */
+class UserHostChanged(metadata: EventMetadata, val user: User, val newIdent: String, val newHost: String) : IrcEvent(metadata)
+
 /**
  * Raised when a user's account changes (i.e., they auth'd or deauth'd with services).
  *

src/main/kotlin/com/dmdirc/ktirc/events/handlers/UserStateHandler.kt

             is ChannelNamesReceived -> handleNamesReceived(client, event)
             is UserAccountChanged -> handleAccountChanged(client, event)
             is UserNickChanged -> handleNickChanged(client, event)
+            is UserHostChanged -> handleHostChanged(client, event)
             is UserQuit -> handleQuit(client.userState, event)
         }
     }
         }
     }
 
+    private fun handleHostChanged(client: IrcClient, event: UserHostChanged) {
+        client.userState[event.user]?.details?.let {
+            it.ident = event.newIdent
+            it.hostname = event.newHost
+        }
+    }
+
     private fun handleQuit(state: UserState, event: UserQuit) {
         state -= event.user
     }

src/main/kotlin/com/dmdirc/ktirc/messages/ChangeHostProcessor.kt

+package com.dmdirc.ktirc.messages
+
+import com.dmdirc.ktirc.events.UserHostChanged
+import com.dmdirc.ktirc.model.IrcMessage
+
+internal class ChangeHostProcessor : MessageProcessor {
+
+    override fun process(message: IrcMessage) = message.sourceUser?.let {
+        listOf(UserHostChanged(message.metadata, it, String(message.params[0]), String(message.params[1])))
+    } ?: emptyList()
+
+    override val commands = arrayOf("CHGHOST")
+
+}

src/main/kotlin/com/dmdirc/ktirc/messages/MessageProcessor.kt

         AuthenticationProcessor(),
         BatchProcessor(),
         CapabilityProcessor(),
+        ChangeHostProcessor(),
         ISupportProcessor(),
         JoinProcessor(),
         KickProcessor(),

src/test/kotlin/com/dmdirc/ktirc/events/handlers/UserStateHandlerTest.kt

         assertNull(userState["AcidBurn"])
         assertEquals("acid~", userState["acid~"]?.details?.nickname)
     }
+
+    @Test
+    fun `updates details for remote host changes`() {
+        val user = User("acidBurn", "libby", "root.localhost")
+        userState += User("AcidBurn")
+
+        handler.processEvent(ircClient, UserHostChanged(EventMetadata(TestConstants.time), user, "burn", "root.gibson"))
+
+        assertEquals("burn", userState["acidBurn"]?.details?.ident)
+        assertEquals("root.gibson", userState["acidBurn"]?.details?.hostname)
+    }
+
 }

src/test/kotlin/com/dmdirc/ktirc/messages/ChangeHostProcessorTest.kt

+package com.dmdirc.ktirc.messages
+
+import com.dmdirc.ktirc.model.IrcMessage
+import com.dmdirc.ktirc.model.User
+import com.dmdirc.ktirc.params
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+
+internal class ChangeHostProcessorTest {
+
+    private val processor = ChangeHostProcessor()
+
+    @Test
+    fun `does nothing if no prefix is supplied`() {
+        val events = processor.process(IrcMessage(emptyMap(), null, "CHGHOST", emptyList()))
+        assertTrue(events.isEmpty())
+    }
+
+    @Test
+    fun `raises event when chghost is received`() {
+        val events = processor.process(IrcMessage(emptyMap(), "acidBurn".toByteArray(), "CHGHOST", params("libby", "root.gibson")))
+        assertEquals(1, events.size)
+        assertEquals(User("acidBurn"), events[0].user)
+        assertEquals("libby", events[0].newIdent)
+        assertEquals("root.gibson", events[0].newHost)
+    }
+
+}