Bug #122881 for WWW-Mechanize-Chrome: After ->get_set_value the $mech object blows up on next call to ->current_form->get

Wed Aug 23 10:09:51 2017 ANDK [...] cpan.org - Ticket created

Subject:

After ->get_set_value the $mech object blows up on next call to ->current_form->get_text

Hi Max, I'd like to ask for some guidance once again and hope you can provide some. In my commit https://github.com/andk/WWW-Mechanize-Chrome/commit/52fe3007336b56604366d8a903bac8e1d1669fa7 I have added tests to t/50-form2.t that illustrate what the subject line says. When I run 50-form2.t after this commit, it consistently dies after "ok 13 - The objectId still matches /injectedScriptId/". The diagnostics that follow say: : Could not find node with given id : : -32000 at /home/andk/src/WWW-Mechanize-Chrome/blib/lib/Chrome/DevToolsProtocol.pm line 302 : # Looks like you planned 22 tests but ran 13. : Dubious, test returned 255 (wstat 65280, 0xff00) : Failed 9/22 subtests When I trace the program I stumble over an 'Ignored message' that is about 'method' => 'DOM.attributeModified' which may or may not be a hint that on_response is required to do something when the message arrives. Do you have a suggestion what to try to get this internal state adjusted?

Wed Aug 23 13:09:20 2017 corion [...] corion.net - Correspondence added

Subject:	Re: [rt.cpan.org #122881] After ->get_set_value the $mech object blows up on next call to ->current_form->get_text
Date:	Wed, 23 Aug 2017 19:09:02 +0200
To:	bug-WWW-Mechanize-Chrome [...] rt.cpan.org
From:	Max Maischein <corion [...] corion.net>

Hello Andreas, thank you very much for trying out W:M:Chrome and for providing me with so good test cases! Show quoted text

> Hi Max, I'd like to ask for some guidance once again and hope you can provide some. > > In my commit https://github.com/andk/WWW-Mechanize-Chrome/commit/52fe3007336b56604366d8a903bac8e1d1669fa7 I have added tests to t/50-form2.t that illustrate what the subject line says. > > When I run 50-form2.t after this commit, it consistently dies after "ok 13 - The objectId still matches /injectedScriptId/". The diagnostics that follow say: > > : Could not find node with given id > : > : -32000 at /home/andk/src/WWW-Mechanize-Chrome/blib/lib/Chrome/DevToolsProtocol.pm line 302 > : # Looks like you planned 22 tests but ran 13. > : Dubious, test returned 255 (wstat 65280, 0xff00) > : Failed 9/22 subtests > > When I trace the program I stumble over an 'Ignored message' that is about 'method' => 'DOM.attributeModified' which may or may not be a hint that on_response is required to do something when the message arrives. > > Do you have a suggestion what to try to get this internal state adjusted? >

No, I don't have a good idea what causes this and how to best remedy this. In theory, the opaque objectId of the form should stay the same even if elements of it are modified, but it seems that Chrome forgets the objectId of the FORM element. Maybe a workaround is to clear all objectIds when seeing a DOM.attributeModified message, but that strikes me as a very rough approach. Also, this is not documented anywhere in the DOM.attributeModified message. But as it clearly depends on $mech->field('id', 99); getting called, the objectId somehow gets lost between calls. This is unfortunate, but maybe I have to find a way to tell Chrome to keep some of those references alive... -max

Wed Aug 23 13:09:20 2017 The RT System itself - Status changed from 'new' to 'open'

Wed Aug 23 16:58:08 2017 corion [...] corion.net - Correspondence added

Subject:	Re: [rt.cpan.org #122881] After ->get_set_value the $mech object blows up on next call to ->current_form->get_text
Date:	Wed, 23 Aug 2017 22:57:27 +0200
To:	bug-WWW-Mechanize-Chrome [...] rt.cpan.org
From:	Max Maischein <corion [...] corion.net>

Hello again, I've pushed a preliminary fix/workaround to github at https://github.com/Corion/WWW-Mechanize-Chrome/commit/3e383913c5d992646e43d2498de5c4fa28889926 This really slows down the tests until I get to implementing a DOM nodeId cache and invalidating that cache, likely whenever the attributeModified message is received. If that change works for you (or fails for you), please tell me! Thanks again for your diagnosis and testing, -max

Thu Aug 24 04:51:25 2017 ANDK [...] cpan.org - Correspondence added

That's awesome, Max, thanks a lot! All tests pass and I can go on experimenting with other form interactions. Stay tuned!

Fri Jul 06 13:26:13 2018 corion [...] cpan.org - Status changed from 'open' to 'resolved'

Fri Jul 06 13:26:14 2018 corion [...] cpan.org - Fixed in 0.07 added

Bug #122881 for WWW-Mechanize-Chrome: After ->get_set_value the $mech object blows up on next call to ->current_form->get_text