Unit test Dispatcher's use of WorkerPool

js/util/dispatcher.js

@@ -19,7 +19,7 @@ function Dispatcher(length, parent) {
     this.currentActor = 0;
     this.id = util.uniqueId();
     var workers = Dispatcher.workerPool.acquire(this.id, length);
-    for (var i = 0; i < length; i++) {
+    for (var i = 0; i < workers.length; i++) {
         var worker = workers[i];
         var actor = new Actor(worker, parent, this.id);
         actor.name = "Worker " + i;

test/js/util/dispatcher.test.js

@@ -0,0 +1,39 @@
+'use strict';
+
+var test = require('tap').test;
+var Dispatcher = require('../../../js/util/dispatcher');
+var WebWorker = require('../../../js/util/web_worker');
+var originalWorkerPool = Dispatcher.workerPool;
+
+test('Dispatcher', function (t) {
+    t.test('requests and releases workers from pool', function (t) {
+        var dispatcher;
+        var workers = [new WebWorker(), new WebWorker()];
+
+        var releaseCalled = [];
+        Dispatcher.workerPool = {
+            acquire: function (id, count) {
+                t.equal(count, 2);
+                return workers;
+            },
+            release: function (id) {
+                releaseCalled.push(id);
+            }
+        };
+
+        dispatcher = new Dispatcher(2, {});
+        t.same(dispatcher.actors.map(function (actor) { return actor.target; }), workers);
+        dispatcher.remove();
+        t.equal(dispatcher.actors.length, 0, 'actors discarded');
+        t.same(releaseCalled, [dispatcher.id]);
+        t.end();
+    });
+
+    t.end();
+});
+
+test('after', function (t) {
+    Dispatcher.workerPool = originalWorkerPool;
+    t.end();
+});
+