Gem::Command#show_lookup_failure

# File tmp/rubies/ruby-3.1.3/lib/rubygems/command.rb, line 158
def show_lookup_failure(gem_name, version, errors, suppress_suggestions = false, required_by = nil)
  gem = "'#{gem_name}' (#{version})"
  msg = String.new "Could not find a valid gem #{gem}"

  if errors && !errors.empty?
    msg << ", here is why:\n"
    errors.each {|x| msg << "          #{x.wordy}\n" }
  else
    if required_by && gem != required_by
      msg << " (required by #{required_by}) in any repository"
    else
      msg << " in any repository"
    end
  end

  alert_error msg

  unless suppress_suggestions
    suggestions = Gem::SpecFetcher.fetcher.suggest_gems_from_name(gem_name, :latest, 10)
    unless suggestions.empty?
      alert_error "Possible alternatives: #{suggestions.join(", ")}"
    end
  end
end