Tighten conn.subscribe() argument checking

Author: Christopher Jones

lib/connection.js

@@ -325,27 +325,13 @@ pingPromisified = nodbUtil.promisify(ping);
 
 // create a subscription which can be used to get notifications of database
 // changes
-function subscribe(name, a2, a3) {
+function subscribe(name, options, subscribeCb) {
   var self = this;
-  var options = {};
-  var subscribeCb;
 
-  nodbUtil.assert(arguments.length >= 2 && arguments.length <= 3, 'NJS-009');
+  nodbUtil.assert(arguments.length == 3, 'NJS-009');
   nodbUtil.assert(typeof name === 'string', 'NJS-006', 1);
-
-  switch (arguments.length) {
-    case 2:
-      nodbUtil.assert(typeof a2 === 'function', 'NJS-006', 2);
-      subscribeCb = a2;
-      break;
-    case 3:
-      nodbUtil.assert(nodbUtil.isObject(a2), 'NJS-006', 2);
-      nodbUtil.assert(typeof a3 === 'function', 'NJS-006', 3);
-      options = a2;
-      subscribeCb = a3;
-      break;
-  }
-
+  nodbUtil.assert(nodbUtil.isObject(options), 'NJS-006', 2);
+  nodbUtil.assert(typeof subscribeCb === 'function', 'NJS-006', 3);
   self._subscribe.call(self, name, options, subscribeCb);
 }