Gem::Commands::CleanupCommand#get_primary_gems

# File tmp/rubies/ruby-3.4.1/lib/rubygems/commands/cleanup_command.rb, line 140
def get_primary_gems
  @primary_gems = {}

  Gem::Specification.each do |spec|
    if @primary_gems[spec.name].nil? ||
       @primary_gems[spec.name].version < spec.version
      @primary_gems[spec.name] = spec
    end
  end
end