Add a reverse complement worker

pkg/obiiter/workers.go

@@ -196,3 +196,11 @@ func SliceWorkerPipe(worker SeqSliceWorker, sizes ...int) Pipeable {
 
 	return f
 }
+
+func ReverseComplementWorker(inplace bool) SeqWorker {
+	f := func(input *obiseq.BioSequence) *obiseq.BioSequence {
+		return input.ReverseComplement(inplace)
+	}
+
+	return f
+}

pkg/obiseq/revcomp.go

@@ -20,5 +20,13 @@ func (sequence *BioSequence) ReverseComplement(inplace bool) *BioSequence {
 		j++
 	}
 
+	if sequence.HasQualities() {
+		s := sequence.qualities
+		for i, j := sequence.Length()-1, 0; i >= j; i-- {
+			s[j], s[i] = s[i], s[j]
+			j++
+		}
+	}
+
 	return sequence
 }