Currently, this is not possible, though your workaround is a nice solution.
Tip: The entry to
gems: array need not be named
jekyll-*. i.e. if your theme is called
.rb file need not be named
omega-jekyll will do just as fine.
In future, if you do plan to release the plugins collection as a rubygem, there's a PR slated for Jekyll v3.5 that will automatically
runtime_dependencies of gem-based themes. With that in place, end-users of theme-gems need not add the plugins required by the theme to their config-file's
Gem::Specification.new do |spec|
spec.name = "omega-jekyll"
spec.version = "0.1.0"
spec.authors = ["John Doe", "Jane Doe"]
spec.add_runtime_dependency "jekyll", "~> 3.5"
spec.add_runtime_dependency "jekyll-sitemap", "~> 1.0"
spec.add_runtime_dependency "omega-jekyll-plugins", "~> 0.1"
Building a site with above will have all the 3 plugins activated.