The default session might be found in `extraSessionFilePackages`, but it's not
viable to detect at evaluation time, so emit a warning.
In LightDM instead of checking `defaultSessionName` against
`displayManager.session.names` we rely on the assertions in
`desktopManager` and `windowMananger` and just check that there's at least one
default set. The second assertion could never actually be triggered.
This makes it easier to support a wider variety of .desktop session files. In
particular this makes it possible to use both the «legacy» sessions and upstream
session files.
We separate `xsession` into two parts, `xsessionWrapper` and `xsession`.
`xsessionWrapper` sets up the correct environment and then lauches the session's
Exec command (from the .desktop file), falling back to launching the default
window/desktopManager through the `xsession` script (required by at least some
nixos tests).
`xsession` then _only_ handles launching desktop-managers/window-managers defined
through `services.xserver.desktopManager.session`.
TryExec needs absolute path too, otherwise the desktop file will be ignored
unless gnome-session is in PATH, in which case, we would not need to patch
Exec.
Pass gnome-session to extraSessionFilePackages, remove unnecessary environment variables, move the rest out of old session option, and then drop the option.
GPaste GNOME Shell extension uses GPaste library generated via introspection. Previously, we added the gpaste package to services.xserver.desktopManager.gnome3.sessionPath option, which
added its typelib directory to GI_TYPELIB_PATH environment variable globally, in order for GNOME Shell to be able to find it. This is not very Nix-y, though, so we have decided to patch the code to
append the path to the GI repository search path.
Additionally, the code relies on GPaste’s GSettings schemas, so we had to hard-code the paths to them as well. We ignored the GNOME Shell’s schemas, since they will already be available for the
extension inside GNOME Shell program.
Previously, the mkDesktops function produced a flat package containing
session files in the top level. As a preparation for introduction of
Wayland sessions, the files will now be placed to $out/share/xsessions.
It seems like Gitlab doesn't pick up GITLAB_UPLOADS_PATH. The internal uploads
folder is already symlinked to /run/gitlab/uploads by the gitlab package. Here
we symlink this further to ${statePath}/uploads, since /run is (usually) a tmpfs.
Lack of 32bit support led to the creation
of an overlay to add it back again,
but since it at least builds and seems to work
don't see why we'd disallow it here :).
