Adapt @show_special to fallback to the dispatch without mime-type...

[lgoettgens]

...if not applicable

Furthermore some doc fixes and enhancements.

cc @fingolfin

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.58%. Comparing base (a49b43f) to head (9ab4b6a).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1663      +/-   ##
==========================================
- Coverage   86.92%   86.58%   -0.35%     
==========================================
  Files         115      116       +1     
  Lines       29692    29673      -19     
==========================================
- Hits        25810    25691     -119     
- Misses       3882     3982     +100     

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[fingolfin]

Is the Hecke doctest failure genuine (and perhaps due to this PR "fixing" something?), or a fluke, or something else?!

[lgoettgens]

Is the Hecke doctest failure genuine (and perhaps due to this PR "fixing" something?), or a fluke, or something else?!

Yes, this is "fixing" some printing in Hecke and Oscar. So let's wait with this for the larger printing changes. I'll split off the documentation fixes into a separate PR. I had a mistake in calling applicable here, that should now fix the tests. The printing changes in the failed doctests are something we potentially want to have, but that should be changed downstream in the round of breaking releases.

[lgoettgens]

The one failure is oscar-system/Oscar.jl#3576.

[fingolfin]

OscarCI#release test failing due to

Starting tests for /home/runner/.julia/packages/Oscar/59YCS/test/Aqua.jl
WARNING: Method definition number_of_generators(AbstractAlgebra.PolyRing{T} where T) in module AbstractAlgebra at /home/runner/work/AbstractAlgebra.jl/AbstractAlgebra.jl/src/Poly.jl:201 overwritten in module Oscar at /home/runner/.julia/packages/Oscar/59YCS/src/Rings/mpoly-affine-algebras.jl:241.
ERROR: Method overwriting is not permitted during Module precompilation. Use `__precompile__(false)` to opt-out of precompilation.

which I believe is not caused by this PR. So merging anyway.