We spent a whole afternoon debugging this, because upstream has very
bad software quality and the error messages were incredibly
misleading.
So let’s document it for the sanity of other people.
Btw, I think the implementation of our module is pretty brittle,
especially the part about diffing tokens to check whether they
changed. We should rather just request a new builder registration
every time, it’s not that much overhead, and always set `replace` so
it is idempotent.
zsh-autosuggestions supports having fallback strategies expressed
through the ZSH_AUTOSUGGEST_STRATEGY array. For example,
`ZSH_AUTOSUGGEST_STRATEGY=(history completion)`. We should also support
this.
In issue #157787 @martined wrote:
Trying to use confinement on packages providing their systemd units
with systemd.packages, for example mpd, fails with the following
error:
system-units> ln: failed to create symbolic link
'/nix/store/...-system-units/mpd.service': File exists
This is because systemd-confinement and mpd both provide a mpd.service
file through systemd.packages. (mpd got updated that way recently to
use upstream's service file)
To address this, we now place the unit file containing the bind-mounted
paths of the Nix closure into a drop-in directory instead of using the
name of a unit file directly.
This does come with the implication that the options set in the drop-in
directory won't apply if the main unit file is missing. In practice
however this should not happen for two reasons:
* The systemd-confinement module already sets additional options via
systemd.services and thus we should get a main unit file
* In the unlikely event that we don't get a main unit file regardless
of the previous point, the unit would be a no-op even if the options
of the drop-in directory would apply
Another thing to consider is the order in which those options are
merged, since systemd loads the files from the drop-in directory in
alphabetical order. So given that we have confinement.conf and
overrides.conf, the confinement options are loaded before the NixOS
overrides.
Since we're only setting the BindReadOnlyPaths option, the order isn't
that important since all those paths are merged anyway and we still
don't lose the ability to reset the option since overrides.conf comes
afterwards.
Fixes: https://github.com/NixOS/nixpkgs/issues/157787
Signed-off-by: aszlig <aszlig@nix.build>