Bug 431292 - Language KCM should install language-pack-${LANG} and then run "sudo apt install `check-language-support`" on debian-based distro to complete language support
Summary: Language KCM should install language-pack-${LANG} and then run "sudo apt inst...
Alias: None
Product: systemsettings
Classification: Applications
Component: kcm_language (show other bugs)
Version: 5.19.5
Platform: Other Linux
: NOR wishlist
Target Milestone: ---
Assignee: Eike Hein
: 430803 (view as bug list)
Depends on:
Reported: 2021-01-08 08:43 UTC by soredake
Modified: 2022-07-02 09:30 UTC (History)
7 users (show)

See Also:
Latest Commit:
Version Fixed In:


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Description soredake 2021-01-08 08:43:16 UTC
check-language-support on ubuntu will install missing languages/dictionaries for selected language/format.

1. Got formats/language kcm.
2. Change language.
3. No `check-language-support` is run after selecting another language/format.

No `check-language-support` is run after selecting another language/format.

`check-language-support` is run after selecting another language/format.

Linux/KDE Plasma: Kubuntu 20.10
(available in About System)
KDE Plasma Version: 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.14.2

Comment 1 soredake 2021-01-08 08:45:22 UTC
Gnome doing this already https://launchpadlibrarian.net/345780979/Language%20Support%20Not%20Installed.png
Comment 2 soredake 2021-01-09 09:46:06 UTC

As i know now, check-language-support relies on language-pack-${LANG} package to install missing languages for apps, so after user switches language kde needs to do two things:

1. install package language-pack-${LANG} to selected by user language
2. ask to run check-language-support to actually install missing language packs for apps
Comment 3 soredake 2021-01-09 09:46:35 UTC
And locales for selected language needs to be generated, too.
Comment 4 soredake 2021-01-09 09:47:47 UTC
For locales there are report https://bugs.kde.org/show_bug.cgi?id=384451
Comment 5 soredake 2021-01-09 10:01:30 UTC
Actually, kcm does not need to generate locales, to generate locales it only needs to pull language-pack-ru, which itself pulls language-pack-ru-base, which itself generates locales in postinst using "/usr/share/locales/install-language-pack" command
Comment 6 soredake 2021-01-09 10:08:58 UTC
Gnome has utility to to all of this (installing language-pack-${LANG}, and running `check-language-support`), https://packages.ubuntu.com/groovy/language-selector-gnome
Comment 7 David Edmundson 2021-01-09 18:02:28 UTC
Can you provide an upstream link of where "check-language-support" comes from?
And what bug this solves
Comment 8 soredake 2021-01-10 08:58:56 UTC

For example, initially my system was set to english, and now i'm switching language/locales to ukrainian, this creates two problems:

1. locales for selected formats/language is not generated, which causes LC_* env to fallback to 
"C.UTF-8" which creates problems like ark not opening archives correctly and other bugs, see https://bugs.kde.org/show_bug.cgi?id=384451 https://bugs.kde.org/show_bug.cgi?id=430803
2. language packs and dictionaries (you can see it if you run `check-language-support --show-installed`) such as "firefox-locale-uk gimp-help-uk hunspell-uk and other" are not installed, leaving user with incomplete language support after switching.

Installing `language-pack-${LANG}` after switching to corresponding language will fix problem one as this package generates locales, and user will have properly translated (instead of C.UTF-8) and working system (no ark problems or crashes related to C.UTF-8).

Running `check-language-support` after switch to another language will install missing language packs and dictionaries.

As you see, these two things can fix problems and make users happy, including me, who faced problems after switching language and locales.
Comment 9 Bug Janitor Service 2021-01-25 04:33:13 UTC
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
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If you have already provided the requested information, please
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Comment 10 soredake 2021-01-25 13:13:40 UTC
I provided needed info.
Comment 11 soredake 2021-04-30 13:33:26 UTC
Fedora has similar package https://pagure.io/system-config-language
Comment 12 Harald Sitter 2021-05-03 11:45:07 UTC
Related: https://invent.kde.org/plasma/plasma-workspace/-/merge_requests/560

I'm not quite sure how the Formats KCM factors into this though.

It doesn't really need language-support, what it needs is locale definitions and I believe those only need compiling via locale-gen (which in turn is simply a wrapper for localedef). Someone would need to do research how all this ought to __actually__ work. Like, currently the formats KCM models QLocale's locale list but I'm sure that internally relies on Qt's embedded locale data not the system's theoretically generatable ones (/usr/share/i18n/locales). Then the locales need generating if they don't already exist (locale -a). Once the locale is generated it'd need adding to some file in /etc presumably (locale.gen?)


From glancing over the documention I don't expect the formats KCM needs distro specific code at all, it just needs to actually wire into the system-level locale infrastructure properly via a privileged kauth helper.
Comment 13 Nate Graham 2021-09-30 17:52:54 UTC
*** Bug 430803 has been marked as a duplicate of this bug. ***
Comment 14 hanyoung 2022-07-02 09:30:51 UTC
Git commit 134e2d5c989c36ac0e985ee0ae382996c6b7b56e by Han Young.
Committed on 02/07/2022 at 09:29.
Pushed by hanyoung into branch 'master'.

merge Language and Formats
Related: bug 192019, bug 341235, bug 344588, bug 394477, bug 397974, bug 397975, bug 403580, bug 417564, bug 420268, bug 429474, bug 444772, bug 446785, bug 447787, bug 448324, bug 448355, bug 451919, bug 451944, bug 454991

closes https://invent.kde.org/plasma/plasma-workspace/-/issues/23

M  +1    -0    .kde-ci.yml
M  +52   -8    CMakeLists.txt
M  +2    -1    config-workspace.h.cmake
D  +0    -2    doc/kcontrol/formats/CMakeLists.txt
D  +0    -63   doc/kcontrol/formats/index.docbook
R  +1    -1    doc/kcontrol/region_language/CMakeLists.txt [from: doc/kcontrol/translations/CMakeLists.txt - 063% similarity]
R  +-    --    doc/kcontrol/region_language/go-top.png [from: doc/kcontrol/translations/go-top.png - 100% similarity]
R  +36   -23   doc/kcontrol/region_language/index.docbook [from: doc/kcontrol/translations/index.docbook - 050% similarity]
A  +-    --    doc/kcontrol/region_language/list-remove.png
D  +-    --    doc/kcontrol/translations/list-remove.png
M  +1    -2    kcms/CMakeLists.txt
D  +0    -30   kcms/formats/CMakeLists.txt
D  +0    -5    kcms/formats/Messages.sh
D  +0    -61   kcms/formats/formatssettings.kcfg
D  +0    -80   kcms/formats/kcmformats.cpp
D  +0    -34   kcms/formats/kcmformats.h
D  +0    -183  kcms/formats/localelistmodel.cpp
D  +0    -140  kcms/formats/optionsmodel.cpp
D  +0    -126  kcms/formats/package/contents/ui/main.qml
A  +75   -0    kcms/region_language/CMakeLists.txt
A  +8    -0    kcms/region_language/Messages.sh
R  +2    -27   kcms/region_language/exampleutility.cpp [from: kcms/formats/exampleutility.cpp - 052% similarity]
A  +22   -0    kcms/region_language/exampleutility.h     [License: GPL(v2.0+)]
A  +82   -0    kcms/region_language/kcm_regionandlang.desktop [TRAILING SPACE] ** [TRAILING SPACE] **
R  +4    -4    kcms/region_language/kcm_regionandlang.json [from: kcms/formats/kcm_formats.json - 098% similarity]
A  +250  -0    kcms/region_language/kcmregionandlang.cpp     [License: GPL(v2.0+)]
A  +58   -0    kcms/region_language/kcmregionandlang.h     [License: GPL(v2.0+)]
A  +372  -0    kcms/region_language/languagelistmodel.cpp     [License: GPL(v2.0+)]
A  +100  -0    kcms/region_language/languagelistmodel.h     [License: GPL(v2.0+)]
A  +30   -0    kcms/region_language/localegenerator.cpp     [License: LGPL(v2.0+)]
A  +17   -0    kcms/region_language/localegenerator.h     [License: LGPL(v2.0+)]
A  +19   -0    kcms/region_language/localegeneratorbase.cpp     [License: GPL(v2.0+)]
A  +23   -0    kcms/region_language/localegeneratorbase.h     [License: GPL(v2.0+)]
A  +32   -0    kcms/region_language/localegeneratorglibc.cpp     [License: GPL(v2.0+)]
A  +24   -0    kcms/region_language/localegeneratorglibc.h     [License: GPL(v2.0+)]
A  +101  -0    kcms/region_language/localegeneratorubuntu.cpp     [License: GPL(v2.0+)]
A  +27   -0    kcms/region_language/localegeneratorubuntu.h     [License: GPL(v2.0+)]
A  +36   -0    kcms/region_language/localegenhelper/CMakeLists.txt
A  +187  -0    kcms/region_language/localegenhelper/localegenhelper.cpp     [License: GPL(v2.0+)]
A  +46   -0    kcms/region_language/localegenhelper/localegenhelper.h     [License: GPL(v2.0+)]
A  +20   -0    kcms/region_language/localegenhelper/org.kde.localegenhelper.conf
A  +21   -0    kcms/region_language/localegenhelper/org.kde.localegenhelper.policy
A  +8    -0    kcms/region_language/localegenhelper/org.kde.localegenhelper.service.in
A  +158  -0    kcms/region_language/localelistmodel.cpp     [License: GPL (v2+)]
R  +22   -22   kcms/region_language/localelistmodel.h [from: kcms/formats/localelistmodel.h - 060% similarity]
A  +197  -0    kcms/region_language/optionsmodel.cpp     [License: GPL(v2.0+)]
R  +21   -11   kcms/region_language/optionsmodel.h [from: kcms/formats/optionsmodel.h - 054% similarity]
A  +204  -0    kcms/region_language/package/contents/ui/AdvancedLanguageSelectPage.qml     [License: LGPL(v3.0+)]
A  +238  -0    kcms/region_language/package/contents/ui/main.qml     [License: LGPL(v3.0+)]
A  +64   -0    kcms/region_language/regionandlangsettings.cpp     [License: GPL(v2.0+)]
A  +21   -0    kcms/region_language/regionandlangsettings.h     [License: GPL(v2.0+)]
A  +37   -0    kcms/region_language/regionandlangsettingsbase.kcfg
R  +2    -2    kcms/region_language/regionandlangsettingsbase.kcfgc [from: kcms/formats/formatssettings.kcfgc - 055% similarity]
A  +17   -0    kcms/region_language/settingtype.h     [License: GPL(v2.0+)]
D  +0    -49   kcms/translations/CMakeLists.txt
D  +0    -2    kcms/translations/Messages.sh
D  +0    -191  kcms/translations/language.cpp
D  +0    -32   kcms/translations/language.h
D  +0    -312  kcms/translations/package/contents/ui/main.qml
D  +0    -86   kcms/translations/translations.cpp
D  +0    -53   kcms/translations/translations.h
D  +0    -193  kcms/translations/translationsmodel.cpp
D  +0    -72   kcms/translations/translationsmodel.h
D  +0    -27   kcms/translations/translationssettings.cpp
D  +0    -24   kcms/translations/translationssettings.h
D  +0    -28   kcms/translations/translationssettingsbase.kcfg
D  +0    -6    kcms/translations/translationssettingsbase.kcfgc

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