Headless CI on GitHub Actions

Continuous integration for program that plot or need a display can be tricky since CI systems in general may not have a display server. macOS can do headless testing using its built-in display server. Linux and Windows runners may require a virtual display server if graphical output is involved, say dumping plots to disk and comparing.

There are headless GitHub Action workflows like pyvista/setup-headless-display-action that enable Linux or Windows runners to run headless graphical tests.

- name: Run headless test
  uses: pyvista/setup-headless-display-action

Take note of the options that allow selecting Weston as the virtual display server.