fix: "start" should wait for "stop" to remove the pid file(using Promise) (#1220)

bin/cli.js

@@ -48,7 +48,9 @@ program.parse(process.argv);
 
 
 function start(options) {
-  stop(options);
+  stop(options)
+    // wait for "stop" method to remove the pid file
+    .then(function () {
       var dataDir = options.dataDir || path.join(process.env.HOME, '.cnpmjs.org');
       mkdirp.sync(dataDir);
 
@@ -88,12 +90,17 @@ function start(options) {
       });
 
       fs.writeFileSync(path.join(dataDir, 'pid'), process.pid + '');
+    });
 }
 
 function stop(options) {
   var dataDir = options.dataDir || path.join(process.env.HOME, '.cnpmjs.org');
   var pidfile = path.join(dataDir, 'pid');
-  if (fs.existsSync(pidfile)) {
+  return new Promise(function (resolve) {
+    if (!fs.existsSync(pidfile)) {
+      resolve();
+      return;
+    }
     var pid = Number(fs.readFileSync(pidfile, 'utf8'));
     treekill(pid, function (err) {
       if (err) {
@@ -102,8 +109,9 @@ function stop(options) {
       }
       console.log('cnpmjs.org server:%d stop', pid);
       fs.unlinkSync(pidfile);
+      resolve();
+    });
   });
-  }
 }
 
 function initDatabase(callback) {