.

wcfs/internal/xbtree/rangeset.go

@@ -53,7 +53,10 @@ func (S *RangeSet) Del(k Key) {
 	S.DelRange(Range{lo: k, hi_: k})
 }
 
-// XXX Has?
+// Has returns whether key k belongs to the set.
+func (S *RangeSet) Has(k Key) bool {
+	return S.HasRange(Range{lo: k, hi_: k})
+}
 
 
 // AddRange adds Range r to the set.
@@ -231,6 +234,10 @@ func (S *RangeSet) DelRange(r Range) {
 	// done
 }
 
+// HasRange returns whether all keys from Range r belong to the set.
+func (S *RangeSet) HasRange(r Range) bool {
+	panic("TODO")
+}
 
 
 // Union returns RangeSet(A.keys | B.keys).

wcfs/internal/xbtree/treediff.go

@@ -533,8 +533,8 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackSet PPTreeSubSet)
 	Bktodo := func(lo, hi_ Key) {	// XXX func(r KeyRange)
 		panic("TODO")
 		/* XXX reenable
+		if !Bkdone.HasRange(r) {
 			δtodo := r.Difference(Bkdone)	// XXX name
-		if !δtodo.Empty() {
 			tracef("    Bkq <- %s\n", δtodo)
 			Bkqueue.UnionInplace(δtodo)
 		}