Prevent AssertionError

[calve]

For ununderstood reasons, my sphinx tree fails to build with the following stacktrace. This patch prevent this. I do not really understand what happened here so any comment is welcomed : )

Please let me know if I can add information.

Not yet converged, rendering again...
100% [========================================] ETA 00:00 (00:53)

Exception occurred:
  File "/home/goudale/.virtualenvs/diplodocus3/lib/python3.5/site-packages/rinoh/document.py", line 458, in create_outlines
    assert section.level == current_level + 1
AssertionError
The full traceback has been saved in /tmp/sphinx-err-tyt5znkg.log, if you want to report the issue to the developers.
Please also report this if it was a user error, so that a better error message can be provided next time.
A bug report can be filed in the tracker at <https://github.com/sphinx-doc/sphinx/issues>. Thanks!
make: *** [Makefile:149: rinoh] Error 1

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All committers have signed the CLA.

[coveralls]

Coverage decreased (-39.3%) to 46.037% when pulling 05f0932 on calve:patch-1 into 3478f0b on brechtm:master.

[coveralls]

Coverage decreased (-39.3%) to 46.037% when pulling 05f0932 on calve:patch-1 into 3478f0b on brechtm:master.

[coveralls]

Coverage decreased (-39.3%) to 46.037% when pulling 05f0932 on calve:patch-1 into 3478f0b on brechtm:master.

[coveralls]

Coverage decreased (-39.3%) to 46.037% when pulling 05f0932 on calve:patch-1 into 3478f0b on brechtm:master.

[coveralls]

Coverage decreased (-39.3%) to 46.037% when pulling 05f0932 on calve:patch-1 into 3478f0b on brechtm:master.

[brechtm]

Thanks for the bug report and suggested fix!

The create_outlines function is responsible for creating the hierarchy of bookmarks in the PDF that link to each section. The assert statement you removed is in fact a sanity check; it assures that no levels are skipped. A section should not be directly followed by a sub-sub-section, for example.

Could you supply me with the Sphinx project that causes the crash? Or better yet, a minimal example that triggers the problem? I'd like to find the root cause of the problem.

BTW Please note that you need to accept the CLA before I can accept pull requests.

[calve]

Thanks for the update.

A section should not be directly followed by a sub-sub-section, for example.

Indeed, I have documents with multiple autogenerated-cross-inclusions which probably fall under this case. IMHO a warning should be raised but should not make the build fails.

I'll try to send you a minimal example in the next few days.

[brechtm]

@calve Have you had any time to construct a minimal example yet? If possible, I'd like to include a fix in the next release. If you can provide me with the full Sphinx project sources, that is fine too.

[calve]

@brechtm I just want to let you know that I aknowledge your request. I'm having some troubles to set up a minimal example reproducing the bug.
Also, sometimes that the bug does not occurs, depending how sphinx is invoqued, and more specifically it appear to depend of the internal sphinx _build/doctrees folder state . I need more investigation, and will keep you updated.

[brechtm]

Thanks for the update!

I understand this is not a trivial problem (and may reveal a Sphinx bug). I'll take your suggestion and issue a warning instead of crashing for the next release. The root cause can be solved at a later point.