Error message from `desktop-file-validate`

[tsujan]

A Gentoo user told me about the error message of desktop-file-validate with the LXQt category here. I can reproduce it with the desktop files of LXQt config; for example:

$ desktop-file-validate /usr/share/applications/lxqt-config.desktop
/usr/share/applications/lxqt-config.desktop: error: value "Settings;DesktopSettings;Qt;LXQt;" for key "Categories" in group "Desktop Entry" contains an unregistered value "LXQt"; values extending the format should start with "X-"

In short, it says that we should have used X-LXQt instead of LXQt. I haven't encountered any problem about it but I think that it deserves mentioning.

Any idea?

[hmollercl]

That happens on debian with lintian too. https://lintian.debian.org/tags/desktop-entry-invalid-category.html According to lintian, the categories should be one of this: https://specifications.freedesktop.org/menu-spec/latest/apas02.html And giving that X-LXQt wll produce the same result. I wonder how can LXQt enter in the freedesktop categories.

[tsujan]

And giving that X-LXQt wll produce the same result

No, it won't, with desktop-file-validate (in Arch). When I replace LXQt with X-LXQt in a test file, there's no error.

[tsujan]

A way of looking at it: This is a "double standard" — KDE creates no error, for example — so, stick with LXQt until they recognize it.

[hmollercl]

I tried and in Ubuntu also X-LXQt solves de lintian issue.

[darkshram]

Here is my opinion regarding this issue.

First it's important to highlight 'LXQt' is supported by desktop-file-utils since version 0.23 (released on 2016-06-19):

============
Version 0.23
============

 desktop-file-validate
  - Accept version 1.1 desktop files (Matthias Clasen).
  - Add Cinnamon, EDE and LXQt to the list of registered desktop environments
    (fdo#73497, fdo#56353, fdo#79561) (Michael Webster, David Faure,
    Jauhien Piatlicki).
  - Allow multipart/related MIME type; it's used for MHTML (fdo#93376)
    (Hans Petter Jansson).
  - Ensure DBusActivatable filenames conform to reverse-DNS notation
    (fdo#66904) (Hans Petter Jansson).
  - Downgrade trailing semicolons to optional (fdo#76902) (Jerome Leclanche).
  - Fix buffer over-read (fdo#94303) (Hans Petter Jansson; reported by
    Hanno Boeck and Agostino Sarubbo).

Specifically with this piece of code from src/validate.c:

/* This should be the same list as in xdg-specs/menu/menu-spec.xml */
static const char *show_in_registered[] = {
    "GNOME", "GNOME-Classic", "GNOME-Flashback", "KDE", "LXDE", "LXQt", "MATE", "Razor", "ROX", "TDE", "Unity", "XFCE", "EDE", "Cinnamon", "Pantheon", "Budgie", "Enlightenment", "Deepin", "Old"
};

So using if desktop-file-utils fails to validate desktop files using 'LXQt' and can only Ok the desktop files with 'X-LXQt', means the OS uses desktop-file-utils < 0.23 (version 0.22 dates from 2013-08-29), and most likely needs to upgrade desktop-file-utils.

Gentoo has available desktop-file-utils 0.24 and 0.25, both versions support 'LXQt. ArchLinux has 0.26 available (latest version). So the Gentoo user should check the installed version of desktop-file-utils and upgrade if needed.

Packagers from OSs and users building from source using desktop-file-tuils < 0.23 may do the following to fix this issue:

desktop-file-edit \
   --remove-only-show-in=LXQt \
   --add-only-show-in=X-LXQt \
    any-desktop-file-from-lxqt.desktop

My suggestion would be to check for desktop-file-utils >= 0.23 and simply warns users about desktop-file-utils < 0.23 and ask them to edit desktop files.

[Chiitoo]

For Gentoo, 's/0.25/0.26/'. :]

In any case, to my understanding, the fix was only for 'OnlyShowIn', or at least the issue with the category has still been there after said fix.

Some more history:

• https://github.com/lxqt/lxqt/issues/155
• https://bugs.gentoo.org/512074
• https://bugs.freedesktop.org/show_bug.cgi?id=79561
• https://bugs.freedesktop.org/show_bug.cgi?id=79562