class RSpec::Core::ExampleStatusPersister

def persist
  RSpec::Support::DirectoryMaker.mkdir_p(File.dirname(@file_name))
  File.open(@file_name, File::RDWR | File::CREAT) do |f|
    # lock the file while reading / persisting to avoid a race
    # condition where parallel or unrelated spec runs race to
    # update the same file
    f.flock(File::LOCK_EX)
    unparsed_previous_runs = f.read
    f.rewind
    f.write(dump_statuses(unparsed_previous_runs))
    f.flush
    f.truncate(f.pos)
  end
end