kde4support: kstandarddirs_unittest fix

[Alex Merry]

On 21/12/13 11:23, Alex Merry wrote:
> KStandardDirs does not add directories that do not exist, UNLESS they
> are the directory returned by installPrefix().  kde4support does not
> install anything in share/applications, therefore if you install
> kde4support in its own prefix, $PREFIX/share/applications does not get
> added to the resource dirs regardless of what you might set
> XDG_DATA_DIRS to.

Ah, it turns out to be more complicated than that.  While I fixed
Jenkins, I broke the test for people who install everything to the same
location (ie: pretty much everyone).

If $PREFIX/share/applications does not exist, KStandardDirs will not add
it.  It will then notice that nothing matching the installation prefix
was added, and add installPath("xdgdata-apps"), which is
$PREFIX/share/applications/kde5/.

However, if $PREFIX/share/applications *does* exist, it will add it
(regardless of XDG_DATA_DIRS, because it *always* considers
installPath("kdedir")/share - as well as each $KDEDIRS/share - to be in
XDG_DATA_DIRS), and then *not* add installPath("xdgdata-apps"), because
it determines the installation prefix to have already been dealt with.

Now, a comment in kstandarddirs.cpp (line 1870) says that the latter
case is the correct behaviour; I'm guessing that when you wrote that
(2008), you didn't anticipate the possibility that the installation
directory might not contain share/applications, since KIO installs a
couple of desktop files.

I guess a possible solution is to change the return value of
installPath("xdgdata-apps") to not include the trailing kde5.

Actually, I think we should just install application files directly in
share/applications. (ie: change the value of XDG_APPS_INSTALL_DIR in
KDEInstallDirs.cmake).  It makes everyone's lives more difficult to have
subdirectories (as I discovered while creating and implementing the
MPRIS2 spec - how do you tell applications how to find Amarok's desktop
file: "amarok.desktop" won't work, because it's not in
share/applications, but "kde4-amarok.desktop" or "kde/amarok.desktop"
requires knowing something about the buildsystem magic that installs the
desktop file).

Alex