Re: [w3c/ServiceWorker] Improve handling of extend lifetime promises (#1049)

annevk commented on this pull request.



>        : Output
       :: None
 
-      1. If |event|'s <a>extend lifetime promises</a> is empty, unset |event|'s <a>extensions allowed flag</a> and abort these steps.
-      1. Let |extendLifetimePromises| be an empty array.
-      1. Run the following substeps <a>in parallel</a>:
-          1. *SetupPromiseArray*: Set |extendLifetimePromises| to a copy of |event|'s <a>extend lifetime promises</a>.
-          1. Wait until all the <a>promises</a> in |extendLifetimePromises| settle.
-          1. If the length of |extendLifetimePromises| does not equal the length of |event|'s <a>extend lifetime promises</a>, jump to the step labeled *SetupPromiseArray*.
-          1. Unset |event|'s <a>extensions allowed flag</a>.
-
-      The user agent *should not* <a lt="terminate service worker">terminate</a> the [=/service worker=] associated with |event|'s <a>relevant settings object</a>'s [=environment settings object/global object=] until |event|'s <a>extensions allowed flag</a> is unset. However, the user agent *may* impose a time limit to this lifetime extension.
+      1. Wait, [=in parallel=], until |promise| is settled and |promise|'s <code>then</code> methods, if any, in the task where |promise| has been settled have executed.
+      2. [=Queue a microtask=], on |promise|'s [=relevant settings object=]'s [=responsible event loop=], to decrease |event|'s [=ExtendableEvent/pending promises count=] by one.

Just queue a task to decrease the thing. It doesn't have to be a microtask.

Queue a microtask from a parallel thread is racy as you say, since you don't know what task it ends up in. User agents only have the ability to queue tasks to get things into the main thread.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/w3c/ServiceWorker/pull/1049