Demi Marie Obenour <demiobenour@gmail.com> writes:

> Due to a systemd bug [1], building systemd-sysupdate does not require
> that systemd-pull is built as well.  However, systemd-sysupdate has a
> run-time dependency on systemd-pull.  Therefore, override the systemd
> derivation so that systemd-pull is built.  Confusingly, this requires
> enabling systemd-importd.
>
> If systemd-pull or systemd-sysupdate is not built, the resulting image
> will be broken and users will not be able to recover without either a
> reinstall or reverting to the previous version.  Therefore, add a check
> to ensure that both are in fact built.  Use 'cat' rather than just
> 'stat' to catch broken symlinks and the like.
>
> The override can be removed once
> https://github.com/NixOS/nixpkgs/pull/461277 is merged, which builds
> systemd-importd by default on musl.  The tests will be preserved to
> catch any regressions.
>
> [1]: https://github.com/systemd/systemd/issues/39635
>
> Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
> ---
> Changes since v2:
>
> - Add link to upstream Nixpkgs issue.
> ---
>  host/rootfs/default.nix | 24 ++++++++++++++++++++++--
>  1 file changed, 22 insertions(+), 2 deletions(-)

We now have the Nixpkgs fix.  Given that there's also an upstream fix in
systemd, I don't think this is likely to regress, so my plan is to just
skip this patch.

(Hopefully we end up with an integration test for updates, which would
catch this anyway.)