Gem::Commands::PushCommand#resolve_gem_name

# File tmp/rubies/ruby-4.1.0-preview1/lib/rubygems/commands/push_command.rb, line 112
def resolve_gem_name(names)
  platform = options[:platform] && Gem::Platform.new(options[:platform])
  ruby_abi = options[:ruby_abi]

  candidates = names.filter_map do |name|
    [name, Gem::Package.new(name).spec]
  rescue Gem::Package::FormatError => e
    alert_warning "Skipping #{name}: #{e.message}"
    nil
  end

  matches = candidates.select do |_, spec|
    (!platform || spec.platform == platform) &&
      (!ruby_abi || (Gem::ContentAddress.eligible?(spec) && spec.ruby_abi == ruby_abi))
  end

  raise Gem::CommandLineError, "No gem matched #{gem_name_selector_description}" if matches.empty?
  raise Gem::CommandLineError, multiple_matches_message(matches) if matches.length > 1

  matches.first.first
end