diff --git a/lib/utils/locker.js b/lib/utils/locker.js
index 82f6fb20..05b88605 100644
--- a/lib/utils/locker.js
+++ b/lib/utils/locker.js
@@ -33,8 +33,7 @@ function Locker(parent, add) {
   this.pendingMap = {};
   this.add = add;
 
-  this._unlock = this.unlock.bind(this);
-  this._unlocker = this.unlocker.bind(this);
+  this.unlocker = this.unlock.bind(this);
 }
 
 utils.inherits(Locker, EventEmitter);
@@ -90,28 +89,18 @@ Locker.prototype.lock = function lock(arg1, arg2) {
   }
 
   if (this.busy) {
+    if (object) {
+      this.pending.push(object);
+      this.pendingMap[object.hash('hex')] = true;
+    }
     return new Promise(function(resolve, reject) {
-      if (object) {
-        self.pending.push(object);
-        self.pendingMap[object.hash('hex')] = true;
-      }
       self.jobs.push([resolve, object]);
     });
   }
 
   this.busy = true;
 
-  return new Promise(this._unlock);
-};
-
-/**
- * Unlock callback to resolve a promise.
- * @param {Function} resolve
- * @param {Function} reject
- */
-
-Locker.prototype.unlock = function unlock(resolve, reject) {
-  resolve(this._unlocker);
+  return Promise.resolve(this.unlocker);
 };
 
 /**
@@ -119,7 +108,7 @@ Locker.prototype.unlock = function unlock(resolve, reject) {
  * @private
  */
 
-Locker.prototype.unlocker = function unlocker() {
+Locker.prototype.unlock = function unlock() {
   var item, resolve, object;
 
   this.busy = false;
@@ -141,7 +130,7 @@ Locker.prototype.unlocker = function unlocker() {
 
   this.busy = true;
 
-  resolve(this._unlocker);
+  resolve(this.unlocker);
 };
 
 /**
@@ -233,9 +222,7 @@ MappedLock.prototype.lock = function lock(key, force) {
 
   this.busy[key] = true;
 
-  return new Promise(function(resolve, reject) {
-    resolve(self.unlock(key));
-  });
+  return Promise.resolve(this.unlock(key));
 };
 
 /**
@@ -247,7 +234,7 @@ MappedLock.prototype.lock = function lock(key, force) {
 
 MappedLock.prototype.unlock = function unlock(key) {
   var self = this;
-  return function unlock() {
+  return function unlocker() {
     var jobs = self.jobs[key];
     var resolve;
 
@@ -264,7 +251,7 @@ MappedLock.prototype.unlock = function unlock(key) {
 
     self.busy[key] = true;
 
-    resolve(unlock);
+    resolve(unlocker);
   };
 };