class Bundler::CLI::Exec

def ruby_shebang?(file)
  possibilities = [
    "#!/usr/bin/env ruby\n",
    "#!/usr/bin/env jruby\n",
    "#!/usr/bin/env truffleruby\n",
    "#!#{Gem.ruby}\n",
  ]
  if File.zero?(file)
    Bundler.ui.warn "#{file} is empty"
    return false
  end
  first_line = File.open(file, "rb") {|f| f.read(possibilities.map(&:size).max) }
  possibilities.any? {|shebang| first_line.start_with?(shebang) }
end