test

#code
def write_pid
  puts "writing pid"
  begin
     File.open(PID_FILE, ::File::CREAT | ::File::EXCL | ::File::WRONLY){|f| f.write("#{Process.pid}") }
       at_exit { File.delete(PID_FILE) if File.exist?(PID_FILE) }
  rescue Errno::EEXIST              
    check_status        
    retry
  end
end

#test

it "should raise Errno::EEXIST if PID_FILE already exists" do
  stub_const("MirrorSyncDaemon::PID_FILE", './testfile.pid')
  File.new(MirrorSyncDaemon::PID_FILE, 'w+')
  allow(mirrorsyncdaemon).to receive(:checkstatus) {} 
  expect(File).to receive(:open).with(MirrorSyncDaemon::PID_FILE, ::File::CREAT | ::Fil    e::EXCL | ::File::WRONLY).and_raise(Errno::EEXIST)
  mirrorsyncdaemon.write_pid
  FileUtils.rm(MirrorSyncDaemon::PID_FILE) if File.exist?(MirrorSyncDaemon::PID_FILE)
end