global

def analyze_patchset(patchset, depth = 0)

whether the patchset represents changes to be made.
Diff::LCS::Change objects to the object form of same) and detection of
single-pass normalization (conversion of the array form of
This method will analyze the provided patchset to provide a 
def analyze_patchset(patchset, depth = 0)
  raise "Patchset too complex" if depth > 1
  has_changes = false
  # Format:
  # [ # patchset
  #   # hunk (change)
  #   [ # hunk
  #     # change
  #   ]
  # ]
  patchset = patchset.map do |hunk|
    case hunk
    when Diff::LCS::Change
      has_changes ||= !hunk.unchanged?
      hunk
    when Array
      # Detect if the 'hunk' is actually an array-format
      # Change object.
      if Diff::LCS::Change.valid_action? hunk[0]
        hunk = Diff::LCS::Change.from_a(hunk)
        has_changes ||= !hunk.unchanged?
        hunk
      else
        with_changes, hunk = analyze_patchset(hunk, depth + 1)
        has_changes ||= with_changes
        hunk.flatten
      end
    else
      raise ArgumentError, "Cannot normalise a hunk of class #{hunk.class}."
    end
  end
  [ has_changes, patchset.flatten(1) ]
end