readthedocs.org: Recent build failures for Godot Engine docs ("godot" project)

Details

• Project URL: https://readthedocs.org/projects/godot
• Build URL (if applicable):
  • Timeout: https://readthedocs.org/projects/godot/builds/6631323/
  • ImportError: no module named debug: https://readthedocs.org/projects/godot/builds/6631922/
  • IOError: [Errno 2] No such file or directory: '/home/docs/checkouts/readthedocs.org/user_builds/godot/envs/latest/local/lib/python2.7/site-packages/readthedocs_ext/_templates/readthedocs-insert.html.tmpl': https://readthedocs.org/projects/godot/builds/6631962/
• Read the Docs username (if applicable): Akien

Expected Result

Godot documentation should build successfully.

Actual Result

Godot has a pretty heavy documentation (GitHub repo) due to a very high number of pages (600-700 pages I think, including ~500 pages of API reference), many of those including images and hyperlinks to each other (especially in the API reference).

This seems to cause various issues, which are a bit hard to reproduce (at least each build seems to give me different errors today…):

• We already had random build issues due to flirting too much with the set timeout of 1800 s (sphinx-build takes ages), as shown in this build log. Lately it happens a lot more.
• Yesterday, I ran into several out of memory issues making the build abort. Strangely enough, today those error messages are no longer visible in the logs of those builds, which only report a build timeout…
• Today, I’m getting two new issues (so far):
  • ImportError: no module named debug: https://readthedocs.org/projects/godot/builds/6631922/
  • IOError: [Errno 2] No such file or directory: '/home/docs/checkouts/readthedocs.org/user_builds/godot/envs/latest/local/lib/python2.7/site-packages/readthedocs_ext/_templates/readthedocs-insert.html.tmpl': https://readthedocs.org/projects/godot/builds/6631962/

So I’m a bit at a loss here, any help welcome 😃 I’d gladly split the various issues mentioned above in separate tickets if relevant; as I had a hard time reproducing them I went for a bulk issue to start going further in debugging with your help.