To be precise, it strips from each line a number of spaces equal to the minimal indentation of the string as a whole (disregarding the indentation of empty lines).

How do I enable a systemd service? I'm trying to write an additional installer test and added this:

extraInstallerConfig = {
      environment.systemPackages = [ pkgs.stratis-cli ];
      systemd.packages = [ pkgs.stratisd ];
    };

But I'm getting an error:

machine # Execution failed:
machine # It appears that there is no stratisd process running.

machine # [    7.637952] systemd[1]: Started Stratis daemon.
(finished: must succeed: systemctl start stratisd, in 0.42 seconds)
machine: must succeed: stratis pool create my-pool /dev/vda
machine # [    7.655736] systemd[1]: Finished Permit User Sessions.
machine # [    7.682901] systemd[1]: Started Getty on tty1.
machine # [    7.684328] systemd[1]: Reached target Login Prompts.
machine # [    7.743384] dhcpcd[649]: eth0: soliciting an IPv6 router
machine # Execution failed:
machine # It appears that there is no stratisd process running.
machine # 

It prints this:

machine: Terminal is ready (there is no initial prompt):
2023/05/07 10:24:47 socat[35] E tcgetattr(0, 0x5555555f9ac0): Inappropriate ioctl for device
(finished: subtest: Create the NixOS configuration, in 1.14 seconds)

Now I'm getting an error during nixos-install:

machine # copying path '/nix/store/bhhb91angi23wsr42apz1in1n9b9ilg3-glibc-2.37-8-dev' to 'local'...
machine # warning: error: unable to download 'https://ftpmirror.gnu.org/bash/bash-5.2-patches/bash52-002': Couldn't resolve host name (6); retrying in 2149 ms
machine # error: unable to download 'https://ftpmirror.gnu.org/autoconf/autoconf-2.71.tar.xz': Couldn't resolve host name (6)
machine # error: filesystem error: cannot rename: Invalid cross-device link [/mnt/nix/store/c99ihlhb2lh875spzsl6rnc4058grxvn-autoconf-2.71.tar.xz.drv.chroot/nix/store/g3pzpdicszf700d5xffyk939jzxa4r2k-autoconf-2.71.tar.xz] [/nix/store/g3pzpdicszf700d5xffyk939jzxa4r2k-autoconf-2.71.tar.xz]
machine: output: 
Test "Perform the installation" failed with error: "command `nixos-install < /dev/null >&2` failed (exit code 1)"
cleanup
kill machine (pid 5)
machine # qemu-kvm: terminating on signal 15 from pid 4 (/nix/store/6jx4nc20v3cfphlbypqid30q41i5vh5x-python3-3.10.11/bin/python3.10)
(finished: cleanup, in 0.12 seconds)

It appears completely unrelated to what I'm doing 🤷‍♂️