Default to manual mode, prevent multiple #starts

Additionally adds #halt/#disconnect to built-in loopback/ping

lib/robot.js

@@ -120,7 +120,7 @@ var Robot = module.exports = function Robot(opts) {
     this.commands = opts.commands;
   }
 
-  var mode = Utils.fetch(Config, 'mode', 'auto');
+  var mode = Utils.fetch(Config, 'mode', 'manual');
 
   if (mode === 'auto') {
     // run on the next tick, to allow for 'work' event handlers to be set up
@@ -235,6 +235,10 @@ Robot.prototype.initDevices = function(devices) {
 //
 // Returns the result of the work
 Robot.prototype.start = function() {
+  if (this.running) {
+    return;
+  }
+
   var begin = function(callback) {
     Logger.info('Working.');
 
@@ -255,6 +259,7 @@ Robot.prototype.start = function() {
       Logger.fatal(err);
     }
   });
+
   return this;
 };
 
@@ -329,6 +334,8 @@ Robot.prototype.halt = function(callback) {
 
     Async.parallel(fns, callback);
   }.bind(this));
+
+  this.running = false;
 };
 
 // Public: Initialize an adaptor and adds it to @robot.adaptors

lib/test/loopback.js

@@ -23,4 +23,8 @@ Loopback.prototype.connect = function(callback) {
   callback();
 };
 
+Loopback.prototype.disconnect = function(callback) {
+  callback();
+};
+
 Loopback.adaptor = function(opts) { return new Loopback(opts); };

lib/test/ping.js

@@ -30,6 +30,10 @@ Ping.prototype.start = function(callback) {
   callback();
 };
 
+Ping.prototype.halt = function(callback) {
+  callback();
+};
+
 Ping.driver = function(opts) {
   return new Ping(opts);
 };