> In general, calling `Polymer.dom.flush` provides a guarantee that these tasks complete synchronously.
sorry to dig up an old thread, but I was poking around in Polymer 1.0.4 today and discovered that `Polymer.dom.flush` didn't guarantee `dom-if` template rendering after changing the `if` property. Instead, Polymer.Async was necessary to ensure the `if` took effect <http://jsfiddle.net/mnqpcqqd/1/>. `Polymer.dom.flush` does seem to work in recent versions of Polymer, but the fact that it was insufficient in a previous 1.0 release worries me. We rely on this in tests to avoid excessive async functions. I just wanted to clarify whether we can consider `Polymer.dom.flush` sufficient to stamp the template nowadays, or if it's just an implementation detail that may revert to 1.0.4 behavior at any time. On Mon, Jul 27, 2015 at 10:30 AM Steve Orvell <[email protected]> wrote: > For efficiency, Polymer queues dynamic changes that provoke Shady DOM > distribution (changes that fill insertion points, e.g. <content>) and > template rendering (e.g. `dom-if` and `dom-repeat`) and processes them at > microtask timing. In addition, the Custom Elements polyfill processes > dynamic dom changes (upgrading elements and calling attached/detached) at > microtask timing. > > In general, calling `Polymer.dom.flush` provides a guarantee that these > tasks complete synchronously. > > On Thu, Jul 16, 2015 at 7:25 PM, Michael Giuffrida <[email protected] > > wrote: > >> It would be really nice if anyone could provide a more detailed answer to >> this and similar questions: It's not clear what operations are supposed to >> be synchronous or asynchronous (and when async operations are at task level >> vs. microtask level), which affects tests but also some more complicated UI >> logic. >> >> I started a thread last week which didn't get any responses. I would >> appreciate even a simple "we make no guarantees" response if that's the >> case, because it would help knowing how defensive our code should be. >> >> Michael >> >> On Thu, Jul 16, 2015 at 4:02 PM, 'Daniel Freedman' via Polymer < >> [email protected]> wrote: >> >>> Generally you can get away with not using flush. >>> >>> You may still need flush for testing element lifecycle callbacks in >>> polyfilled browsers, or measuring DOM, but I expect very few cornercases >>> like that. >>> >>> On Thu, Jul 16, 2015 at 10:46 AM, <[email protected]> wrote: >>> >>>> With Polymer 1.0, observers are now evaluated synchronously. If I have >>>> an element whose behavior is driven by observers on attributes, and >>>> everything appears to work in synchronous tests, is there any reason to >>>> call flush()? That is, is it necessary that I call it before/after each >>>> test? >>>> >>>> Follow Polymer on Google+: plus.google.com/107187849809354688692 >>>> --- >>>> You received this message because you are subscribed to the Google >>>> Groups "Polymer" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/polymer-dev/adc4db0a-459d-4abf-ab8f-6453dae62213%40googlegroups.com >>>> <https://groups.google.com/d/msgid/polymer-dev/adc4db0a-459d-4abf-ab8f-6453dae62213%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> Follow Polymer on Google+: plus.google.com/107187849809354688692 >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "Polymer" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/polymer-dev/CAAUAVAhtWUNOMEw8Zm2Nq5JVA0Q4ihDEtgPJ4pDjRVqZHk1ENA%40mail.gmail.com >>> <https://groups.google.com/d/msgid/polymer-dev/CAAUAVAhtWUNOMEw8Zm2Nq5JVA0Q4ihDEtgPJ4pDjRVqZHk1ENA%40mail.gmail.com?utm_medium=email&utm_source=footer> >>> . >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> Follow Polymer on Google+: plus.google.com/107187849809354688692 >> --- >> You received this message because you are subscribed to the Google Groups >> "Polymer" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/polymer-dev/CACi5S_1DeF4B%2BkgPzwpW8rt%3DH1dw%2B2%3D1C_BbGqgdzuD5ZtPpQw%40mail.gmail.com >> <https://groups.google.com/d/msgid/polymer-dev/CACi5S_1DeF4B%2BkgPzwpW8rt%3DH1dw%2B2%3D1C_BbGqgdzuD5ZtPpQw%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . > > >> For more options, visit https://groups.google.com/d/optout. >> > Follow Polymer on Google+: plus.google.com/107187849809354688692 --- You received this message because you are subscribed to the Google Groups "Polymer" group. 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