Fix documentation generation

[kelson42]

Fixes #595

[codecov]

Codecov Report

Merging #598 (7d790eb) into master (855dfe0) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #598   +/-   ##
=======================================
  Coverage   82.78%   82.78%           
=======================================
  Files          91       91           
  Lines        3822     3822           
  Branches     1703     1703           
=======================================
  Hits         3164     3164           
  Misses        657      657           
  Partials        1        1           

Impacted Files	Coverage Δ
include/zim/search.h	100.00% <ø> (ø)
include/zim/search_iterator.h	100.00% <ø> (ø)

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[kelson42]

@mgautierfr Now it passes for me localy but it fails on the CI! Like stated earlier by @maneeshpm #574 (comment), my own research tends to lead to sphinx-doc/sphinx#9433 and breathe-doc/breathe#711

[kelson42]

I have tried to setup a .readthedocs.yml, without success. Looks like ReadTheDocs is using an old version of Doxygen and the problem might come from there.

[maneeshpm]

@kelson42 I believe you are correct. Can we try specifying the version of doxygen(the latest one) or the version of sphinx(the previous version) on our side?

[kelson42]

@maneeshpm I don't know how, not even sure this is possible