QtQuick V4 Date.Parse() does not support RFC2822 date format

            var datestring = "Wed, 18 Sep 2013 07:00:51 -0700"
            console.log("Date.parse: ", Date.parse(datestring))

console output: Date.parse: NaN

this code works fine with v8 js engine in Qt 5.0.2 but fail with v4 js engine in Qt 5.2

I had a conversation with a dev in Qt project, he said this issue will be fixed in Qt 5.3

https://bugreports.qt-project.org/browse/QTBUG-38011 - link to upstream qt bug

Hope that Qt 5.3 will be available in time
01 апр. 2014 г. 12:45 пользователь "Joey Chan" <email address hidden> написал:
>
> var datestring = "Wed, 18 Sep 2013 07:00:51 -0700"
> console.log("Date.parse: ", Date.parse(datestring))
>
> console output: Date.parse: NaN
>
> this code works fine with v8 js engine in Qt 5.0.2 but fail with v4 js
> engine in Qt 5.2
>
> I had a conversation with a dev in Qt project, he said this issue will
> be fixed in Qt 5.3
>
> --
> You received this bug notification because you are a member of Ubuntu
> RSS Feed Reader Developers, which is subscribed to Ubuntu RSS Feed
> Reader App.
> Matching subscriptions: Ubuntu RSS Reader Bugmail
> https://bugs.launchpad.net/bugs/1298978
>
> Title:
> Articles are missing dates
>
> Status in RSS Feed Reader application for Ubuntu devices:
> Confirmed
>
> Bug description:
> I'm seeing no dates on articles, and this in the log a lot:-
>
>
file:///usr/share/click/preinstalled/com.ubuntu.shorts/0.2.179/RssFeedPage.qml:338:
> ReferenceError: pubdate is not defined
>
> To manage notifications about this bug go to:
>
https://bugs.launchpad.net/ubuntu-rssreader-app/+bug/1298978/+subscriptions

Looks like the same issue in our bitcoin-app:
  We get dates in the form of "Sat, 15 Mar 2014 16:40:20 +0000", and pass that into new Date(). In the current promoted image (250?), this results in 'Invalid Date'.

Need to test if QDateTime::fromString() can handle this format
https://qt-project.org/doc/qt-5.0/qtcore/qdatetime.html

Looking at the parsing code there is not case for this, it seems to not be either JS std or Qt std
https://qt.gitorious.org/qt/qtdeclarative/source/722dcd2c315acc2bab1cfa9072986ca66a5bba88:src/qml/jsruntime/qv4dateobject.cpp

If QtDateTIme can handle it we may simply need to add a case for the other formats.

I think the fix is adding these lines
if (!dt.isValid())
        dt = QDateTime::fromString(s, Qt::RFC2822Date);

to qv4dateobject.cpp

Hope that works ...

Pat's suggested fix seems to work. The fix is now testable from https://launchpad.net/~ci-train-ppa-service/+archive/landing-008

In other words, to test:
adb shell
apt-add-repository ppa:ci-train-ppa-service/landing-008
apt-get update
apt-get upgrade

Qt Declarative's own test suite passed fine. I'll run our autopilot suites also to check if there are any regressions. If there are none I'll submit the fix to upstream and publish the fix after it has seen some sort of approval.

Note that the shorts app caches the entries, so the time will only be displayed for new ones or if the database is removed. On desktop one can do rm -rf .local/share/com.ubuntu.shorts/ for simple with/without testing.

thanks Timo for your work

But I can't do any "apt-get upgrade" on r250 which will cause "black screen" after reboot

or can I just replace some .so file ?

Joey: you're right, if you're not using latest trusty-proposed you probably shouldn't experiment with apt-get upgrade.

So, instead, you can try the following:
adb shell
apt-add-repository ppa:ci-train-ppa-service/landing-008
apt-get update
apt-get install libqt5qml5 libqt5quick5 libqt5quickparticles5 qmlscene qtdeclarative5-folderlistmodel-plugin qtdeclarative5-localstorage-plugin qtdeclarative5-particles-plugin qtdeclarative5-qtquick2-plugin qtdeclarative5-window-plugin qtdeclarative5-xmllistmodel-plugin

That only updates the Qt Declarative parts. To restore the old version, you can run:
apt-get install ppa-purge
ppa-purge ppa:ci-train-ppa-service/landing-008

Oh yeah !!! everything works just like before :D

Thanks Timo for your effort

Another good news is, this bug in Qt upstream has been closed and marked done hours ago

Thanks Joey for the confirmation :) Since there were also zero regressions in AP test runs, I published the qtdeclarative. It'll take some time for it to pass through the queues.

This bug was fixed in the package qtdeclarative-opensource-src - 5.2.1-3ubuntu13

---------------
qtdeclarative-opensource-src (5.2.1-3ubuntu13) trusty; urgency=medium

  * debian/patches/Support-RFC2822Date-date-format-similar-to-V8.patch
    - Support RFC 2822 format (LP: #1298978)
 -- Timo Jyrinki <email address hidden> Thu, 03 Apr 2014 05:55:24 +0000

Now this bug appears again in my utopic r106

sth wrong with Qt ?

I found UT has upgraded its Qt to 5.3.0, but I remember this bug had been fixed in upstream, why it happened again ?

I downloaded official 5.3.1 , this bug has been fixed in this version

Pls upgrade to 5.3.1 ASAP, thx

I'll upload a fixed Qt Declarative 5.3.0 with the patch again included.

Upstream believed this was fixed in 5.3.0 even without the patch. However, I see the problem in both Ubuntu's Qt 5.3.0 and Debian's Qt 5.3.1 with the attached test.qml, but it works with the patch.

I'm not sure if it's a local vs system-wide install issue, if using upstream installer gives a working functionality?

Thx Timo for your remind, official Qt 5.3.1 do not fix this bug, I just used the wrong qmlscene to execute the qml file

Now I can confirm that both Ubuntu's 5.3.0 and Digia's 5.3.1 can reproduce this bug.

Now fixed again in qtdeclarative-opensource-src 5.3.0-3ubuntu7, which is included on phone image #122 (and above).

lol THX Timo