scorch zap merge optimize newDocNums lookup to outside of loop

And, also a "go fmt".

index/scorch/introducer.go

@@ -130,14 +130,14 @@ func (s *Scorch) introduceSegment(next *segmentIntroduction) error {
 			segment:    s.root.segment[i].segment,
 			cachedDocs: s.root.segment[i].cachedDocs,
 		}
-		
+
 		// apply new obsoletions
 		if s.root.segment[i].deleted == nil {
 			newss.deleted = delta
 		} else {
 			newss.deleted = roaring.Or(s.root.segment[i].deleted, delta)
 		}
-		
+
 		// check for live size before copying
 		if newss.LiveSize() > 0 {
 			newSnapshot.segment = append(newSnapshot.segment, newss)
@@ -241,7 +241,7 @@ func (s *Scorch) introduceMerge(nextMerge *segmentMerge) {
 			// the root segments would be the obsolete segment set
 			delete(nextMerge.old, segmentID)
 
-		} else if s.root.segment[i].LiveSize() > 0 { 
+		} else if s.root.segment[i].LiveSize() > 0 {
 			// this segment is staying
 			newSnapshot.segment = append(newSnapshot.segment, &SegmentSnapshot{
 				id:         s.root.segment[i].id,
@@ -269,7 +269,7 @@ func (s *Scorch) introduceMerge(nextMerge *segmentMerge) {
 			}
 		}
 	}
-	// In case where all the docs in the newly merged segment getting 
+	// In case where all the docs in the newly merged segment getting
 	// deleted by the time we reach here, can skip the introduction.
 	if nextMerge.new != nil &&
 		nextMerge.new.Count() > newSegmentDeleted.GetCardinality() {

index/scorch/merge.go

@@ -16,7 +16,7 @@ package scorch
 
 import (
 	"bytes"
-  	"encoding/json"
+	"encoding/json"
 
 	"fmt"
 	"os"

index/scorch/persister.go

@@ -68,7 +68,6 @@ OUTER:
 		persistWatchers = s.pausePersisterForMergerCatchUp(lastPersistedEpoch,
 			&lastMergedEpoch, persistWatchers)
 
-
 		var ourSnapshot *IndexSnapshot
 		var ourPersisted []chan error
 

index/scorch/segment/zap/merge.go

@@ -316,10 +316,12 @@ func persistMergedRest(segments []*SegmentBase, dropsIn []*roaring.Bitmap,
 				return nil, 0, err2
 			}
 
+			newDocNumsI := newDocNums[itrI]
+
 			postItr = postings.iterator(postItr)
 			next, err2 := postItr.Next()
 			for next != nil && err2 == nil {
-				hitNewDocNum := newDocNums[itrI][next.Number()]
+				hitNewDocNum := newDocNumsI[next.Number()]
 				if hitNewDocNum == docDropped {
 					return nil, 0, fmt.Errorf("see hit with dropped doc num")
 				}