}

// lineRetractLess returns whether li should be sorted before lj for lines in
// a "retract" block. It treats each line as a version interval. Single versions
// are compared as if they were intervals with the same low and high version.
// Intervals are sorted in descending order, first by low version, then by
// high version, using semver.Compare.
func lineRetractLess(li, lj *Line) bool {