class Test::Unit::Diff::UnifiedDiffer

def same_content?(groups)
  return false if groups.size != 1
  group = groups[0]
  return false if group.size != 1
  tag, from_start, from_end, to_start, to_end = group[0]
  tag == :equal and [from_start, from_end] == [to_start, to_end]
end