Re: [whatwg] Navigation triggered from unload
On 06/12/2012 08:56 PM, Boris Zbarsky wrote: On 6/12/12 6:30 AM, James Graham wrote: Based on some tests ([1]-[5]), it seems that WebKit seems to cancel the navigation in the unload handler always, Opera seems to always carry out the navigation in the unload handler, and Gecko seems to follow WebKit in the cross-origin case and Opera in the same-origin case. In all cases the unload handler is only called once. [1] http://hoppipolla.co.uk/tests/navigation/003.html [2] http://hoppipolla.co.uk/tests/navigation/004.html [3] http://hoppipolla.co.uk/tests/navigation/005.html [4] http://hoppipolla.co.uk/tests/navigation/006.html [5] http://hoppipolla.co.uk/tests/navigation/007.html For what it's worth, we initially tried to do what you say WebKit does but ran into web compat issues. See https://bugzilla.mozilla.org/show_bug.cgi?id=371360 for the original bug where we blocked all navigation during unload and https://bugzilla.mozilla.org/show_bug.cgi?id=409888 for the bug where we changed to the current behavior. I believe the spec says what it says based on our implementation experience here... Hmm, so I wonder if the WebKit people consider it a problem that they don't pass the tests in those bug reports. I couldn't find any of the original sites still responding, so it's hard to know if there is still a compat. problem here. If there isn't, the greater conceptual simplicity of the WebKit model is quite appealing. P.S. Opera's behavior is not quite as simple as you describe: as far as I can tell it depends on whether the unload is happening due to the user typing something in the url bar or due to the user clicking a link, say. That seems to be true. On the other hand it appears that gecko will still respect navigation from unload even if the unload was triggered by explicit user interaction (e.g. by editing the address bar), as long as all the origins match, so you can end up at a different page to the one you expected. That is very surprising behaviour (although I see that you can argue that it is possible in other ways).
Re: [whatwg] Navigation triggered from unload
On 6/12/12 6:30 AM, James Graham wrote: Based on some tests ([1]-[5]), it seems that WebKit seems to cancel the navigation in the unload handler always, Opera seems to always carry out the navigation in the unload handler, and Gecko seems to follow WebKit in the cross-origin case and Opera in the same-origin case. In all cases the unload handler is only called once. [1] http://hoppipolla.co.uk/tests/navigation/003.html [2] http://hoppipolla.co.uk/tests/navigation/004.html [3] http://hoppipolla.co.uk/tests/navigation/005.html [4] http://hoppipolla.co.uk/tests/navigation/006.html [5] http://hoppipolla.co.uk/tests/navigation/007.html For what it's worth, we initially tried to do what you say WebKit does but ran into web compat issues. See https://bugzilla.mozilla.org/show_bug.cgi?id=371360 for the original bug where we blocked all navigation during unload and https://bugzilla.mozilla.org/show_bug.cgi?id=409888 for the bug where we changed to the current behavior. I believe the spec says what it says based on our implementation experience here... -Boris P.S. Opera's behavior is not quite as simple as you describe: as far as I can tell it depends on whether the unload is happening due to the user typing something in the url bar or due to the user clicking a link, say.
[whatwg] Navigation triggered from unload
What is the expected behaviour of navigation triggered from unload handlers? In particular, what stops such navigations from re-triggering the unload handler, and thus starting yet another navigation? It looks like the spec tries to make a distinction between navigations that are cross-origin and those that are not (step 4 in the "navigating across documents" algorithm); I'm not sure why this inconsistency is desirable rather than using the cross-origin approach always. Based on some tests ([1]-[5]), it seems that WebKit seems to cancel the navigation in the unload handler always, Opera seems to always carry out the navigation in the unload handler, and Gecko seems to follow WebKit in the cross-origin case and Opera in the same-origin case. In all cases the unload handler is only called once. [1] http://hoppipolla.co.uk/tests/navigation/003.html [2] http://hoppipolla.co.uk/tests/navigation/004.html [3] http://hoppipolla.co.uk/tests/navigation/005.html [4] http://hoppipolla.co.uk/tests/navigation/006.html [5] http://hoppipolla.co.uk/tests/navigation/007.html
