module Bundler::RubyDsl

def normalize_ruby_file(filename)

Loads the file relative to the dirname of the Gemfile itself.

Intentionally does not support `3.2.1@gemset` since rvm recommends using .ruby-gemset instead

ruby 2.5.1# close comment and extra spaces doesn't confuse
ruby 2.5.1 # comment is ignored

Also supports .tool-versions files for asdf. Lines not starting with "ruby" are ignored.

ruby-3.2.2
3.2.2

Support the various file formats found in .ruby-version files. 
def normalize_ruby_file(filename)
  file_content = Bundler.read_file(gemfile.dirname.join(filename))
  # match "ruby-3.2.2" or "ruby   3.2.2" capturing version string up to the first space or comment
  if /^ruby(-|\s+)([^\s#]+)/.match(file_content)
    $2
  else
    file_content.strip
  end
end

def ruby(*ruby_version) 

def ruby(*ruby_version)
  options = ruby_version.pop if ruby_version.last.is_a?(Hash)
  ruby_version.flatten!
  if options
    patchlevel = options[:patchlevel]
    engine = options[:engine]
    engine_version = options[:engine_version]
    raise GemfileError, "Please define :engine_version" if engine && engine_version.nil?
    raise GemfileError, "Please define :engine" if engine_version && engine.nil?
    if options[:file]
      raise GemfileError, "Do not pass version argument when using :file option" unless ruby_version.empty?
      ruby_version << normalize_ruby_file(options[:file])
    end
    if engine == "ruby" && engine_version && ruby_version != Array(engine_version)
      raise GemfileEvalError, "ruby_version must match the :engine_version for MRI"
    end
  end
  @ruby_version = RubyVersion.new(ruby_version, patchlevel, engine, engine_version)
end