CI: the VideoOut display tests never run on Linux or Windows; under Xvfb they run in 10 s and caught the EOP flip regression #6899

What

17 VideoOut tests skip on the Linux CI job, and Windows CI skips them as well: video_out_flip_{controls,eop,eop_aftergpu,eop_main,labels,labels_main,lifetime,overlay,reopen,unopened}, video_out_frame_dump_queue, video_out_hdr_present and guest_video_out_{hdr,high_frame_rate,output_mode,resolution_status,wqhd_detection}. They use SDL_VIDEODRIVER=offscreen (the ANYPS5_VIDEO_OUT_TEST_DRIVER default from #3810), and SDL2's offscreen driver has no Vulkan surface, so each one reports no display or Vulkan device. tools/check_skips.py accepts that reason, so the job stays green.

This hides real regressions. #1202 (pipelined draws on by default) broke presentation of EOP flips from #5539: video_out_flip_eop and _eop_main fail and _eop_aftergpu times out. CI could not see it; it was found by running the tests by hand and bisecting. The fix is #6616.

Running them under Xvfb

On Ubuntu 24.04 with lavapipe (Mesa 25.2.8):

Xvfb :99 -screen 0 1920x1080x24 -nolisten tcp &
cmake -S . -B build -DANYPS5_VIDEO_OUT_TEST_DRIVER=x11
DISPLAY=:99 ANYPS5_GPU=llvmpipe ctest --test-dir build -R video_out

On main plus #6616, 16 of the 17 run and pass, in 9.9 s for all 21 video_out tests. guest_video_out_high_frame_rate still skips, because Xvfb offers no 120 Hz mode. check_skips.py already accepts that reason. On main without #6616, the three EOP tests fail as described above.

A hardware Vulkan driver cannot present on Xvfb, which has no DRI3: Intel ANV fails with No DRI3 support detected. So this works with lavapipe, which is what the Linux job already uses.

Suggestion

On the self-hosted Linux runner: install xvfb, configure with -DANYPS5_VIDEO_OUT_TEST_DRIVER=x11, and run the ctest step under xvfb-run -a (or with a started Xvfb and DISPLAY set). Once that is in place, check_skips.py could stop accepting no display on the Linux job, so a lost display shows up as a failure instead of a skip. The runner is yours to configure, so I have not opened a workflow PR. I'm happy to send one if this direction is wanted.

AI-assisted: yes.