.

wcfs/δbtail.go

@@ -743,13 +743,24 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx map[zodb.Oid]
 			// Bkqueue <- δA
 			for k := range δA {
 				Akdone.Add(k)
-				Bkqueue.Add(k)
+				if !Bkdone.Has(k) {
+					Bkqueue.Add(k)
+				}
+			}
+			// Bkqueue <- holes(ra.range)
+			for k := range holeIdx.InRange(ra.lo, ra.hi_) {
+				if !Bkdone.Has(k) {
+					Bkqueue.Add(k)
+				}
 			}
-			// XXX Bkqueue <- holes(ra.range)
 			ra.done = true
 
 		case *Tree:
-			// a is tree - expand it and queue children
+			// empty tree - XXX no need to check?
+			if len(a.Entryv()) == 0 {
+			}
+
+			// a is normal tree - expand it and queue children
 			// check for each children whether it can be skipped
 			// XXX if a is ø tree
 			achildren := Av.Expand(ra)
@@ -870,7 +881,12 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx map[zodb.Oid]
 						Bkqueue.Add(k_)
 					}
 				}
-				// XXX Bkqueue <- holes(a.range)
+				// Bkqueue <- holes(a.range)
+				for k_ := range holeIdx.InRange(a.lo, a.hi_) {
+					if !Bkdone.Has(k_) {
+						Bkqueue.Add(k_)
+					}
+				}
 
 				a.done = true
 			}

wcfs/δbtail_test.go

@@ -751,7 +751,7 @@ func testΔBTail(t *testing.T, testq chan ΔBTestEntry) {
 		xkv2 := XGetTree(db, at2, tg.treeRoot)
 
 		subj := fmt.Sprintf("%s -> %s", tree1, tree2)
-		tracef("\n\n\n**** %s ****\n\n\n", subj)
+		tracef("\n\n\n**** %s ****\n\n", subj)
 		xverifyΔBTail(t, subj, db, tg.treeRoot, at1,at2, xkv1,xkv2, δZ, test.kadjOK)
 
 		at1   = at2