Recycle existing User objects in names event

This is required to keep lastMessage correct. This will also be useful for the away tracking PR.

src/models/user.js

@@ -12,13 +12,15 @@ function User(attr, prefixLookup) {
 		lastMessage: 0,
 	});
 
-	// irc-framework sets character mode, but lounge works with symbols
-	this.modes = this.modes.map((mode) => prefixLookup[mode]);
+	this.setModes(this.modes, prefixLookup);
+}
 
-	if (this.modes[0]) {
-		this.mode = this.modes[0];
-	}
-}
+User.prototype.setModes = function(modes, prefixLookup) {
+	// irc-framework sets character mode, but lounge works with symbols
+	this.modes = modes.map((mode) => prefixLookup[mode]);
+
+	this.mode = this.modes[0] || "";
+};
 
 User.prototype.toJSON = function() {
 	return {

src/plugins/irc-events/names.js

@@ -1,19 +1,39 @@
 "use strict";
 
-var User = require("../../models/user");
+const User = require("../../models/user");
 
 module.exports = function(irc, network) {
-	var client = this;
+	const client = this;
+
 	irc.on("userlist", function(data) {
-		var chan = network.getChannel(data.channel);
+		const chan = network.getChannel(data.channel);
 		if (typeof chan === "undefined") {
 			return;
 		}
 
-		chan.users = data.users.map((user) => new User({
+		// Create lookup map of current users,
+		// as we need to keep certain properties
+		// and we can recycle existing User objects
+		const oldUsers = new Map();
+
+		chan.users.forEach((user) => {
+			oldUsers.set(user.nick, user);
+		});
+
+		chan.users = data.users.map((user) => {
+			const oldUser = oldUsers.get(user.nick);
+
+			// For existing users, we only need to update mode
+			if (oldUser) {
+				oldUser.setModes(user.modes, network.prefixLookup);
+				return oldUser;
+			}
+
+			return new User({
 				nick: user.nick,
 				modes: user.modes,
-		}, network.prefixLookup));
+			}, network.prefixLookup);
+		});
 
 		chan.sortUsers(irc);