1 files changed, 23 insertions, 10 deletions
diff --git a/lib/internal/queue.js b/lib/internal/queue.js
index 479eaf8..1a3f4cb 100644
--- a/lib/internal/queue.js
+++ b/lib/internal/queue.js
@@ -1,7 +1,6 @@
 import indexOf from 'lodash/_baseIndexOf';
 import isArray from 'lodash/isArray';
 import noop from 'lodash/noop';
-import rest from './rest';
 
 import onlyOnce from './onlyOnce';
 import setImmediate from './setImmediate';
@@ -20,6 +19,7 @@ export default function queue(worker, concurrency, payload) {
     var numRunning = 0;
     var workersList = [];
 
+    var processingScheduled = false;
     function _insert(data, insertAtFront, callback) {
         if (callback != null && typeof callback !== 'function') {
             throw new Error('task callback must be a function');
@@ -47,24 +47,34 @@ export default function queue(worker, concurrency, payload) {
                 q._tasks.push(item);
             }
         }
-        setImmediate(q.process);
+
+        if (!processingScheduled) {
+            processingScheduled = true;
+            setImmediate(function() {
+                processingScheduled = false;
+                q.process();
+            });
+        }
     }
 
     function _next(tasks) {
-        return rest(function(args){
+        return function(err){
             numRunning -= 1;
 
             for (var i = 0, l = tasks.length; i < l; i++) {
                 var task = tasks[i];
+
                 var index = indexOf(workersList, task, 0);
-                if (index >= 0) {
-                    workersList.splice(index)
+                if (index === 0) {
+                    workersList.shift();
+                } else if (index > 0) {
+                    workersList.splice(index, 1);
                 }
 
-                task.callback.apply(task, args);
+                task.callback.apply(task, arguments);
 
-                if (args[0] != null) {
-                    q.error(args[0], task.data);
+                if (err != null) {
+                    q.error(err, task.data);
                 }
             }
 
@@ -76,7 +86,7 @@ export default function queue(worker, concurrency, payload) {
                 q.drain();
             }
             q.process();
-        });
+        };
     }
 
     var isProcessing = false;
@@ -102,6 +112,9 @@ export default function queue(worker, concurrency, payload) {
         unshift: function (data, callback) {
             _insert(data, true, callback);
         },
+        remove: function (testFn) {
+            q._tasks.remove(testFn);
+        },
         process: function () {
             // Avoid trying to start too many processing operations. This can occur
             // when callbacks resolve synchronously (#1267).
@@ -116,11 +129,11 @@ export default function queue(worker, concurrency, payload) {
                 for (var i = 0; i < l; i++) {
                     var node = q._tasks.shift();
                     tasks.push(node);
+                    workersList.push(node);
                     data.push(node.data);
                 }
 
                 numRunning += 1;
-                workersList.push(tasks[0]);
 
                 if (q._tasks.length === 0) {
                     q.empty();