.

wcfs/internal/xbtree/δbtail.go

@@ -282,7 +282,7 @@ func (δBtail *ΔBtail) rebuildAll() (err error) {
 
 	for root := range trackNewRoots {
 		δTtail := δBtail.vδTbyRoot[root] // must be there
-		δtrackSet, err := δTtail.rebuild(δBtail.δZtail, δBtail.db)
+		δtrackSet, err := δTtail.rebuild(root, δBtail.δZtail, δBtail.db)
 		if err != nil {
 			return err
 		}
@@ -298,7 +298,7 @@ func (δBtail *ΔBtail) rebuildAll() (err error) {
 // It returns set of nodes that must be added to ΔBtail.trackSet to account for
 // keys that becomes tracked. Note: this set is potentially wider compared to what was in .trackNew.
 // XXX place
-func (δTtail *ΔTtail) rebuild(δZtail *zodb.ΔTail, db *zodb.DB) (δtrackSet PPTreeSubSet, err error) {
+func (δTtail *ΔTtail) rebuild(root zodb.Oid, δZtail *zodb.ΔTail, db *zodb.DB) (δtrackSet PPTreeSubSet, err error) {
 	defer xerr.Context(&err, "ΔTtail rebuild")
 	// XXX locking
 
@@ -352,27 +352,42 @@ func (δTtail *ΔTtail) rebuild(δZtail *zodb.ΔTail, db *zodb.DB) (δtrackSet P
 			break
 		}
 
-		top := &nodeInRange{prefix: nil, lo: KeyMin, hi_: KeyMax, node: root}
-		V   := rangeSplit{top}
-		for _, r := δtkeycov.AllRanges() {
-			lo := r.lo
-			for {
-				b, err := V.GetToLeaf(ctx, lo)
-				if err != nil {
-					return nil, err
-				}
+		widenTrackNew := func() error {
+			// XXX errctx, debug
+
+			txn, ctx := transaction.New(context.TODO()) // XXX
+			defer txn.Abort()
+
+			zhead, err := db.Open(ctx, &zodb.ConnOptions{At: δZtail.Head()});  /*X*/ if err != nil { return err }
+
+			xtree, err := zhead.Get(ctx, root);  /*X*/ if err != nil { return err }
+			tree := xtree.(*Tree) // must succeed
 
-				trackNew.AddPath(b.Path())
+			top := &nodeInRange{prefix: nil, lo: KeyMin, hi_: KeyMax, node: tree}
+			V   := rangeSplit{top}
+			for _, r := range δtkeycov.AllRanges() {
+				lo := r.lo
+				for {
+					b, err := V.GetToLeaf(ctx, lo);  /*X*/ if err != nil { return err }
+					trackNew.AddPath(b.Path())
 
-				// continue with next right bucket until r coverage is complete
-				if r.hi_ <= b.hi_ {
-					break
+					// continue with next right bucket until r coverage is complete
+					if r.hi_ <= b.hi_ {
+						break
+					}
+					lo = b.hi_ + 1
 				}
-				lo = b.hi_ + 1
 			}
+			return nil
+		}
+
+		err := widenTrackNew()
+		if err != nil {
+			return nil, err
 		}
 	}
 
+	return trackNew, nil
 
 /*
 	// trackNew was adjusted to correspond to @tail potentially growing its key coverage.
@@ -384,7 +399,6 @@ func (δTtail *ΔTtail) rebuild(δZtail *zodb.ΔTail, db *zodb.DB) (δtrackSet P
 	δBtail.trackSet.UnionInplace(trackNew)
 	return δtrackSet, nil
 */
-	return trackNew
 }
 
 // rebuild1 rebuilds δT for single δZ.