Gem::SpecFetcher#suggest_gems_from_name

# File tmp/rubies/ruby-3.2.0/lib/rubygems/spec_fetcher.rb, line 173
def suggest_gems_from_name(gem_name, type = :latest, num_results = 5)
  gem_name        = gem_name.downcase.tr("_-", "")
  max             = gem_name.size / 2
  names           = available_specs(type).first.values.flatten(1)

  matches = names.map do |n|
    next unless n.match_platform?
    [n.name, 0] if n.name.downcase.tr("_-", "").include?(gem_name)
  end.compact

  if matches.length < num_results
    matches += names.map do |n|
      next unless n.match_platform?
      distance = levenshtein_distance gem_name, n.name.downcase.tr("_-", "")
      next if distance >= max
      return [n.name] if distance == 0
      [n.name, distance]
    end.compact
  end

  matches = if matches.empty? && type != :prerelease
    suggest_gems_from_name gem_name, :prerelease
  else
    matches.uniq.sort_by {|name, dist| dist }
  end

  matches.map {|name, dist| name }.uniq.first(num_results)
end