Dependency rdoc missing for installation of gollum gem

[salexan2001]

Describe the bug

• I installed gollum using "gem install gollum".
• Afterwards I started gollum and received the following error message:

$ gollum
<internal:/usr/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require': cannot load such file -- rdoc (LoadError)
	from <internal:/usr/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'

Installing rdoc using: "gem install rdoc" fixed the problem and let gollum start without errors.

To Reproduce
Already described in bug description.

Expected behavior
I expected "gem install gollum" to fetch all dependencies, including rdoc. I checked the issue tracker and README.md for a note on manual installation of rdoc, but it seems like the dependency is just missing.

Environment Info

$ gollum --versions
Gollum 5.2.3
Running on: x86_64-linux with Ruby version 3.0.3
Using:
rugged 1.1.1
gollum-rugged_adapter 1.1.2
gollum-lib 5.1.3
Markdown rendering gem: kramdown
Other renderering gems:
none

I am running an up-to-date archlinux as OS.

[benjaminwil]

Thanks for reporting. I don't think that rdoc should be a dependency, so I will investigate why that might be and then resolve the issue.

[dometto]

Problems with rdoc on arch have been reported before: #1342

My hunch is arch just does not require the ruby-rdoc package as part of a standard ruby installation, whereas most on most other environments rdoc is at least de facto treated and installed as part of the ruby standard lib. I wonder if it hurts just adding rdoc to the Gemfile.

[benjaminwil]

Ah I see. No, that would not hurt. Perhaps I will add it in the gemspec along with a comment about why we're explicitly adding it as a dependency.

[benjaminwil]

This issue will be resolved in the next released version of the gem.

[dometto]

Released in v5.3.0.