Browser side of ServiceWorker requestSyncEvents() function

content/test/data/service_worker/sync.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var code = 404;

[jsbell, 2014/04/03 21:47:34]

The test would be clearer if the global state was `var sawSyncEvent` to avoid
conflating the test's state (was sync fired?) with the signaling mechanism (200
vs 404)

[jkarlin, 2014/04/04 11:59:09]

Done.

+var fetchCount = 0;
+
+// onfetch is a state machine:
+// 1st call returns 404 and calls requestSyncEvents()
+// .. expect sync call here ..
+// 2nd call returns 200 because sync ran and calls requestSyncEvents(false)
+// .. sync doesn't fire ..
+// 3rd call returns 404 and calls requestSyncEvents(true)
+// .. expect sync call here ..
+// 4th call returns 200 because sync ran
 
 this.onfetch = function(event) {
+    if (fetchCount == 0) {

[jsbell, 2014/04/03 21:47:34]

Since the sync event won't fire until after the event.respondWith() is handled
anyway, IMHO it would be clearer to move this all to the end of the function.
Then the function reads in order with (1) respond with previous state, (2) set
up test for the next state.

(Assuming I'm reading it correctly.)

[jkarlin, 2014/04/04 11:59:09]

Done.  Great suggestions, thanks.

+        requestSyncEvents();
+    } else if (fetchCount == 1) {
+        requestSyncEvents(false);
+    } else if (fetchCount == 2) {
+        requestSyncEvents(true);
+    }
+
+    fetchCount += 1;
+
     response = new Response({
         statusCode: code,

[jsbell, 2014/04/03 21:47:34]

And this would be sawSyncEvent ? 200 : 404;

[jkarlin, 2014/04/04 11:59:09]

Done.

         statusText: 'OK',
         method: 'GET',
         headers: {
             'Content-Language': 'fi',

[jsbell, 2014/04/03 21:47:34]

Just for kicks? :)

[jkarlin, 2014/04/04 11:59:09]

Why not :)

             'Content-Type': 'text/html; charset=UTF-8'
         }
     });
 
+    code = 404;
+
     event.respondWith(new Promise(function(r) {
         setTimeout(function() { r(response); }, 5);
     }));
 };
 
 this.onsync = function(event) {
     code = 200;
 };