++ mktemp -d
+ checkout=/tmp/tmp.KUSxNtydZS
+ trap 'rm -rf "$checkout"' EXIT
+ cp -R /var/lib/ci-tron/sources/b3ba4f1c73ea999b/. /tmp/tmp.KUSxNtydZS
+ cd /tmp/tmp.KUSxNtydZS
+ nix develop --command python3 scripts/headless_test.py
GC Warning: Could not open /proc/stat
headless_test: building term...
headless_test: starting headless sway...
Traceback (most recent call last):
  File "/tmp/tmp.KUSxNtydZS/scripts/headless_test.py", line 582, in <module>
    sys.exit(main(sys.argv[1:]))
             ~~~~^^^^^^^^^^^^^^
  File "/tmp/tmp.KUSxNtydZS/scripts/headless_test.py", line 530, in main
    sway_proc, host_tool_env = start_sway(workdir)
                               ~~~~~~~~~~^^^^^^^^^
  File "/tmp/tmp.KUSxNtydZS/scripts/headless_test.py", line 243, in start_sway
    proc = subprocess.Popen(["sway"], env=sway_env, stdout=sway_log, stderr=subprocess.STDOUT)
  File "/nix/store/vm6nxpp97fxgczw00bwkxdqdm2an3n95-python3-3.13.12/lib/python3.13/subprocess.py", line 1039, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
    ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                        pass_fds, cwd, env,
                        ^^^^^^^^^^^^^^^^^^^
    ...<5 lines>...
                        gid, gids, uid, umask,
                        ^^^^^^^^^^^^^^^^^^^^^^
                        start_new_session, process_group)
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/vm6nxpp97fxgczw00bwkxdqdm2an3n95-python3-3.13.12/lib/python3.13/subprocess.py", line 1991, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'sway'
+ rm -rf /tmp/tmp.KUSxNtydZS