Add reference to Slave in Instance

Add a reference to the Slave that's running the given instance in order
for it to be able to access the slave config.

slave.js

@@ -58,9 +58,10 @@ const instanceFactorioAutosaveSize = new prometheus.Gauge(
  * Keeps track of the runtime parameters of an instance
  */
 class Instance extends link.Link{
-	constructor(connector, dir, factorioDir, instanceConfig) {
+	constructor(slave, connector, dir, factorioDir, instanceConfig) {
 		super('instance', 'slave', connector);
 		link.attachAllMessages(this);
+		this._slave = slave;
 		this._dir = dir;
 
 		this.plugins = new Map();
@@ -141,21 +142,21 @@ class Instance extends link.Link{
 		console.log(`Clusterio | Loaded plugin ${pluginInfo.name} in ${Date.now() - pluginLoadStarted}ms`);
 	}
 
-	async init(pluginInfos, slave) {
+	async init(pluginInfos) {
 		await this.server.init();
 
 		// load plugins
 		for (let pluginInfo of pluginInfos) {
 			if (
 				!pluginInfo.instanceEntrypoint
-				|| !slave.serverPlugins.has(pluginInfo.name)
+				|| !this._slave.serverPlugins.has(pluginInfo.name)
 				|| !this.config.group(pluginInfo.name).get("enabled")
 			) {
 				continue;
 			}
 
 			try {
-				await this._loadPlugin(pluginInfo, slave);
+				await this._loadPlugin(pluginInfo, this._slave);
 			} catch (err) {
 				this.notifyExit();
 				throw err;
@@ -801,9 +802,9 @@ class Slave extends link.Link {
 		let [connectionClient, connectionServer] = link.VirtualConnector.makePair();
 		let instanceConnection = new InstanceConnection(connectionServer, this, instanceId);
 		let instance = new Instance(
-			connectionClient, instanceInfo.path, this.config.get("slave.factorio_directory"), instanceInfo.config
+			this, connectionClient, instanceInfo.path, this.config.get("slave.factorio_directory"), instanceInfo.config
 		);
-		await instance.init(this.pluginInfos, this);
+		await instance.init(this.pluginInfos);
 
 		// XXX: race condition on multiple simultanious calls
 		this.instanceConnections.set(instanceId, instanceConnection);

test/slave.js

@@ -17,7 +17,7 @@ describe("Slave testing", function() {
 			let instanceConfig = new config.InstanceConfig();
 			await instanceConfig.init();
 			instanceConfig.set("instance.name", "foo");
-			instance = new slave._Instance(new link.VirtualConnector(), "dir", "factorioDir", instanceConfig);
+			instance = new slave._Instance({}, new link.VirtualConnector(), "dir", "factorioDir", instanceConfig);
 		});
 
 		describe(".name", function() {
@@ -109,7 +109,7 @@ describe("Slave testing", function() {
 			await instanceConfig.init();
 			instanceConfig.set("instance.name", "test");
 			instance = new slave._Instance(
-				new link.VirtualConnector(), path.join(testDir, "instance"), "factorioDir", instanceConfig
+				{}, new link.VirtualConnector(), path.join(testDir, "instance"), "factorioDir", instanceConfig
 			);
 			await fs.outputFile(instance.path("mods", "mod_i.zip"), "i");
 		});