.

wcfs/δbtail.go

@@ -135,7 +135,7 @@ type ΔValue struct {
 //
 // It covers only changes to keys from tracked subset of BTrees parts.
 // In particular a key that was not explicitly requested to be tracked, even if
-// it was changed in δZ, is not guaranted to be present in δB.
+// it was changed in δZ, is not guaranteed to be present in δB.
 //
 // ΔBtail provides the following operations:
 //
@@ -164,8 +164,8 @@ type ΔBtail struct {
 	δZtail *zodb.ΔTail
 
 	// XXX vvv keys ∈ tracked -> keys ∈ kadj[tracked] ?
-//	δRtail []ΔRoots // which BTree were changed; Noted only by keys ∈ tracket subset
-	byRoot map[zodb.Oid]*ΔTtail // {} root -> [] k/v change history; only for keys ∈ tracket subset
+//	δRtail []ΔRoots // which BTree were changed; Noted only by keys ∈ tracked subset
+	byRoot map[zodb.Oid]*ΔTtail // {} root -> [] k/v change history; only for keys ∈ tracked subset
 
 	// handle to make connections to access database.
 	// TODO allow client to optionally provide zconnOld/zconnNew on e.g. Update()
@@ -312,7 +312,12 @@ func (δBtail *ΔBtail) Track(key Key, keyPresent bool, path []Node) error { //
 	var oldTrack bool
 	for _, node := range path {
 		oid := node.POid()
-		// XXX check for InvalidOid  (e.g. T/B1:a with bucket not having its own oid.
+		// InvalidOid means embedded bucket - e.g. T/B1:a with bucket not having its own oid.
+		//if oid == zodb.InvalidOid {
+		//		// XXX verify node is leaf; else panic
+		//		continue
+		//}
+
 		track, oldTrack = δBtail.trackIdx[oid]
 		if !oldTrack {
 			track = nodeTrack{parent: parent}
@@ -484,6 +489,7 @@ func (δBtail *ΔBtail) δZConnectTracked(δZv *zodb.EventCommit) (δZTC SetOid,
 // XXX place
 // nodeInRange represents a Node coming under [lo, hi_] key range in its tree.
 type nodeInRange struct {
+	// XXX +parent?
 	lo, hi_  Key  // [lo, hi_]	NOTE _not_ hi) not to overflow at ∞
 	node     Node
 	done     bool // whether this node was already taken into account while computing diff
@@ -783,7 +789,7 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx map[zodb.Oid]
 	// a node ac does not contribute to δ- and can be skipped, if:
 	// - ac is not tracked, or
 	// - ac ∉ δZTC && ∃ bc from B: ac.oid == bc.oid	(ac was not changed and stays in the tree)
-	Aq := []*nodeInRange{atop} // queue for A nodes that contribyte to δ-
+	Aq := []*nodeInRange{atop} // queue for A nodes that contribute to δ-
 	for len(Aq) > 0 {
 		tracef("\n")
 		tracef("  aq: %v\n", Aq)

wcfs/δbtail_test.go

@@ -271,7 +271,7 @@ func (tg *AllStructsSrv) AllStructs(kv1, kv2 map[Key]string, maxdepth, maxsplit,
 
 // RTree represents Tree node covering [lo, hi_] key range in its parent tree.
 type RTree struct {
-	oid    Oid
+	oid    zodb.Oid
 	parent *RTree
 	// XXX +children?
 }
@@ -279,7 +279,7 @@ type RTree struct {
 // RBucket represents Bucket node covering [lo, hi_] key range in its Tree.
 // NOTE it is not [lo,hi) but [lo,hi_] instead to avoid overflow at KeyMax.
 type RBucket struct {
-	oid     Oid
+	oid     zodb.Oid
 	parent  *RTree
 	lo, hi_ Key
 	kv      map[Key]string // bucket's k->v; values were ZBlk objects whose data is loaded instead.
@@ -321,6 +321,59 @@ func (rbs RBucketSet) coverage() string {
 	return s
 }
 
+// holeIdx returns what should be ΔBtree.holeIdx for specified tracked key set.
+func (rbs RBucketSet) holeIdx(tracked SetKey) SetKey {
+	holes := SetKey{}
+	for k := range tracked {
+		_, keyin := rbs.Get(k).kv[k]
+		if !keyin {
+			holes.Add(k)
+		}
+	}
+	return holes
+}
+
+// trackIdx returns what should be ΔBtree.trackIdx for specified tracked key set.
+func (rbs RBucketSet) trackIdx(tracked SetKey) map[zodb.Oid]nodeTrack {
+	trackIdx := map[zodb.Oid]nodeTrack{}
+	for k := range tracked {
+		kb := rbs.Get(k)
+		// trackIdx records regular buckets or non-empty embedded bucket
+		// (empty embedded bucket means there is just empty tree node
+		// and only that is recorded in trackIdx)
+		if kb.oid != zodb.InvalidOid || len(kb.kv) != 0 {
+			track, already := trackIdx[kb.oid]
+			if !already {
+				track = nodeTrack{parent: kb.parent.oid}
+				trackIdx[kb.oid] = track
+			}
+			if track.parent != kb.parent.oid {
+				panicf("BUG: %s: B%s -> multiple parents: %s %s", rbs.coverage(), kb.oid, track.parent, kb.parent.oid)
+			}
+		}
+
+		p := kb.parent
+		for p != nil {
+			ppoid := zodb.InvalidOid // oid of p.parent
+			if p.parent != nil {
+				ppoid = p.parent.oid
+			}
+
+			pt, already := trackIdx[p.oid]
+			if !already {
+				pt = nodeTrack{parent: ppoid}
+				trackIdx[p.oid] = pt
+			}
+			if pt.parent != ppoid {
+				panicf("BUG: %s: T%s -> multiple parents: %s %s", rbs.coverage(), p.oid, pt.parent, ppoid)
+			}
+
+			p = p.parent
+		}
+	}
+	return trackIdx
+}
+
 
 
 // XGetTree loads Tree from zurl@at->obj<root>.
@@ -348,7 +401,7 @@ func XGetTree(db *zodb.DB, at zodb.Tid, root zodb.Oid) RBucketSet {
 	})
 	if len(rbucketv) == 0 { // empty tree -> [-∞, ∞){}
 		etree   := &RTree{
-				oid:    zodb.InvalidOid,
+				oid:    root,
 				parent: nil,
 		}
 		ebucket := &RBucket{
@@ -386,7 +439,7 @@ func _xwalkDFS(ctx context.Context, lo, hi_ Key, ztree *Tree, rparent *RTree, bv
 
 		tchild, ok := ev[i].Child().(*Tree)
 		if ok {
-			_xwalkDFS(ctx, xlo, xhi_, tchild, rparent, bvisit)
+			_xwalkDFS(ctx, xlo, xhi_, tchild, rtree, bvisit)
 			continue
 		}
 
@@ -616,19 +669,17 @@ func xverifyΔBTail1(t *testing.T, subj string, db *zodb.DB, treeRoot zodb.Oid,
 
 	// verify δbtail.holeIdx  against @at1
 	// holes1 = tracked1 \ kv1
-	holes1 := SetKey{}
-	for k := range initialTrackedKeys {
-		_, keyin1 := xkv1.Get(k).kv[k]
-		if !keyin1 {
-			holes1.Add(k)
-		}
-	}
+	holes1 := xkv1.holeIdx(initialTrackedKeys)
 	if !reflect.DeepEqual(holes1, δbtail.holeIdx.SetKey) {
 		badf("δbtail.holeIdx1 wrong  ; holeIdx=%v  holeIdxOK=%v", δbtail.holeIdx, holes1)
 	}
 
 	// verify δbtail.trackIdx against @at1
-	// tracked1 = ... XXX
+	// trackIdx1 = xkv1[tracked1]
+	trackIdx1 := xkv1.trackIdx(initialTrackedKeys)
+	if !reflect.DeepEqual(trackIdx1, δbtail.trackIdx) {
+		badf("δbtail.trackIdx1 wrong  ; trackIdx=%v  trackIdxOK=%v", δbtail.trackIdx, trackIdx1)
+	}
 
 
 	// δB <- δZ
@@ -640,20 +691,19 @@ func xverifyΔBTail1(t *testing.T, subj string, db *zodb.DB, treeRoot zodb.Oid,
 
 	// verify δbtail.holeIdx  against @at2
 	// holes2 = tracked2 \ kv2  ( = kadj[tracked1] \ kv2)
-	holes2 := SetKey{}
-	for k := range kadjTracked {
-		_, keyin2 := xkv2.Get(k).kv[k]
-		if !keyin2 {
-			holes2.Add(k)
-		}
-	}
+	holes2 := xkv2.holeIdx(kadjTracked)
 	if !reflect.DeepEqual(holes2, δbtail.holeIdx.SetKey) {
 		badf("δbtail.holeIdx2 wrong  ; holeIdx=%v  holeIdxOK=%v", δbtail.holeIdx, holes2)
 	}
 
-	// XXX verify δbtail index consistency against @at2
-	// XXX verify that removed keys remain in trackedIdx (holes), so that e.g.
-	// track [k]; k:a->b; k:b->ø; k:ø->c is not missed
+	// verify δbtail.traciIdx  against @at2
+	// trackIdx2 = xkv2[tracked2]  ( = xkv2[kadj[tracked1]]
+	/* XXX reenable
+	trackIdx2 := xkv2.trackIdx(kadjTracked)
+	if !reflect.DeepEqual(trackIdx2, δbtail.trackIdx) {
+		badf("δbtail.trackIdx2 wrong  ; trackIdx=%v  trackIdxOK=%v", δbtail.trackIdx, trackIdx2)
+	}
+	*/
 
 
 	// assert δB.ByRoot == {treeRoot -> ...}  if δTok != ø