def changeset
      @changeset ||= git_diff.map do |diff_file|
        file_diff = FileDiff.new(diff_file)
        file_diff unless FormattingChecker.pure_formatting?(file_diff)
      end.compact
    end
def changeset
      @changeset ||= git_diff.map do |diff_file|
        file_diff = FileDiff.new(diff_file)
        file_diff unless FormattingChecker.pure_formatting?(file_diff)
      end.compact
    end
TODO: Include untracked to changeset