.

wcfs/internal/xbtree/rangeset.go

@@ -398,11 +398,13 @@ func (S RangedKeySet) String() string {
 }
 
 func (r KeyRange) String() string {
-	hi := r.hi_
-	if hi < KeyMax {
-		hi += 1
+	var shi string
+	if r.hi_ == KeyMax {
+		shi = kstr(r.hi_) // ∞
+	} else {
+		shi = fmt.Sprintf("%d", r.hi_+1)
 	}
-	return fmt.Sprintf("[%s,%s)", kstr(r.lo), kstr(hi))
+	return fmt.Sprintf("[%s,%s)", kstr(r.lo), shi)
 }
 
 

wcfs/internal/xbtree/treediff.go

@@ -467,16 +467,55 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackSet PPTreeSubSet)
 	}
 
 	var ABoid zodb.Oid
+	var AB *Tree
 	if A != nil {
 		ABoid = A.POid()
+		AB = A
 	}
 	if B != nil {
 		ABoid = B.POid()
+		AB = B
 	}
 
 	// path prefix to A and B
 	ABpath := trackSet.Path(ABoid)
 
+	// key coverage for A and B
+	ABlo  := KeyMin
+	ABhi_ := KeyMax
+	node := AB
+ABcov:
+	for i := len(ABpath)-2; i >= 0; i-- {
+		xparent, err := node.PJar().Get(ctx, ABpath[i]);  /*X*/if err != nil { return nil,nil,nil, err }
+		parent := xparent.(*Tree) // must succeed
+		// find node in parent children and constrain ABlo/ABhi accordingly
+		entryv := parent.Entryv()
+		for j, entry := range entryv {
+			if entry.Child() == node {
+				// parent.entry[j] points to node
+				// [i].Key ≤ [i].Child.*.Key < [i+1].Key
+				klo  := entryv[j].Key()
+				khi_ := KeyMax
+				if j+1 < len(entryv) {
+					khi_ = entryv[j+1].Key() - 1
+				}
+
+				if klo > ABlo {
+					ABlo = klo
+				}
+				if khi_ < ABhi_ {
+					ABhi_ = khi_
+				}
+
+				node = parent
+				continue ABcov
+			}
+		}
+
+		panicf("BUG: T%s points to T%s as parent in trackSet, but not found in T%s children", node.POid(), parent.POid(), parent.POid())
+	}
+
+
 	if A == nil || B == nil {
 		// top of the subtree must stay in the tracking set even if the subtree is removed
 		// this way, if later, the subtree will be recreated, that change won't be missed
@@ -496,11 +535,9 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackSet PPTreeSubSet)
 	}
 
 	// initial split ranges for A and B
-	// FIXME walk till a from root to get more precise initial range
-	// XXX   ^^^ get it from ABpath[-1].keyrange
 	prefix := ABpath[:len(ABpath)-1]
-	atop := &nodeInRange{prefix: prefix, lo: KeyMin, hi_: KeyMax, node: A} // [-∞, ∞)
-	btop := &nodeInRange{prefix: prefix, lo: KeyMin, hi_: KeyMax, node: B} // [-∞, ∞)
+	atop := &nodeInRange{prefix: prefix, lo: ABlo, hi_: ABhi_, node: A} // [-∞, ∞)
+	btop := &nodeInRange{prefix: prefix, lo: ABlo, hi_: ABhi_, node: B} // [-∞, ∞)
 	Av := rangeSplit{atop} // nodes expanded from A
 	Bv := rangeSplit{btop} // nodes expanded from B
 
@@ -638,8 +675,13 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackSet PPTreeSubSet)
 							if nc := at.nchild; nc != 0 {
 								δtrack.δnchildNonLeafs[acOid] = nc
 							}
-							// XXX δtkeycov
-							// debugfDiff("  δtrack - %s %v\n", ar, ra.Path())
+							ar := KeyRange{ac.lo, ac.hi_}
+							bc := Bv.Get(ac.lo)
+							br := KeyRange{bc.lo, bc.hi_}
+							δtkeycovADel.AddRange(ar)
+							δtkeycovBAdd.AddRange(br)
+							debugfDiff("  δtrack - %s %v KKK\n", ar, apath)
+							debugfDiff("  δtrack + %s %v KKK\n", br, bpath)
 						}
 
 						continue
@@ -940,11 +982,7 @@ func xidOf(obj zodb.IPersistent) string {
 
 func (rn *nodeInRange) String() string {
 	done := " ";   if rn.done         { done = "*" }
-	hi := rn.hi_
-	if hi < KeyMax {
-		hi += 1
-	}
-	return fmt.Sprintf("%s[%s,%s)%s", done, kstr(rn.lo), kstr(hi), vnode(rn.node))
+	return fmt.Sprintf("%s%s%s", done, KeyRange{rn.lo, rn.hi_}, vnode(rn.node))
 }
 
 // push pushes element to node stack.

wcfs/internal/xbtree/δbtail_test.go

@@ -1947,12 +1947,7 @@ func sortedKeys(kv map[Key]Δstring) []Key {
 }
 
 func (b *RBucket) String() string {
-	// XXX dup wrt nodeInRange.String
-	hi := b.hi_
-	if hi < KeyMax {
-		hi += 1
-	}
-	return fmt.Sprintf("[%s,%s)B%s{%s}", kstr(b.lo), kstr(hi), b.oid, kvtxt(b.kv))
+	return fmt.Sprintf("%sB%s{%s}", KeyRange{b.lo, b.hi_}, b.oid, kvtxt(b.kv))
 
 }