Add comprehensive tests for role middleware and fix package dependencies

node_modules/mysql2/lib/commands/register_slave.js

@@ -0,0 +1,27 @@
+'use strict';
+
+const Command = require('./command');
+const Packets = require('../packets');
+
+class RegisterSlave extends Command {
+  constructor(opts, callback) {
+    super();
+    this.onResult = callback;
+    this.opts = opts;
+  }
+
+  start(packet, connection) {
+    const newPacket = new Packets.RegisterSlave(this.opts);
+    connection.writePacket(newPacket.toPacket(1));
+    return RegisterSlave.prototype.registerResponse;
+  }
+
+  registerResponse() {
+    if (this.onResult) {
+      process.nextTick(this.onResult.bind(this));
+    }
+    return null;
+  }
+}
+
+module.exports = RegisterSlave;