mobile safari triggers Router.run twice on initial page load

[bmcmahen]

I haven't had too much time to test this in other contexts, but within my app I've noticed that on the initial page load Router.run is triggered twice on the initial page load -- both times with the same state / route information. I haven't noticed this happening in any other browsers. As a quick fix, I've stored the current route information and done the relevant checks to determine if it has, indeed, changed.

[ryanflorence]

interesting, let us know if you discover anything else.

[mjackson]

I think this is a WebKit bug. See

https://bugs.webkit.org/show_bug.cgi?id=93506
https://bugs.webkit.org/show_bug.cgi?id=80697

@bmcmahen Are you using HistoryLocation by any chance? That bug is specific to using the HTML5 history API.

Also, Twitter worked around this bug by ignoring popstate events when the state property is undefined.

[bmcmahen]

Yep, I was using HistoryLocation. I haven't been able to explore the issue all that much more, but I have only encountered it while using mobile safari with HistoryLocation.

[mjackson]

@bmcmahen Thanks for confirming. I'm just going to assume we're running into the same bug that Twitter was for now. Please let us know if you still see this behavior when using 3d8a883.

[dlindenkreuz]

Still getting onPopState event on initial page load with Safari 8.0.6.

Check should be changed from if (event.state === undefined) to if (event.state === null). Apparently, the state property is never undefined.

[ryanzec]

I think this needs to be re-opened as I am still seeing this issue. Following @dlindenkreuz suggestion, I changes that if to:

if (event.state === undefined || event.state === null) {
 return;
}

and it seems to work in safari after that.