.

wcfs/internal/xbtree/pptreesubset.go

@@ -59,7 +59,6 @@ type PPTreeSubSet map[zodb.Oid]*nodeInTree
 type nodeInTree struct {
 	parent  zodb.Oid // parent node | InvalidOid for root
 	nchild  int      // number of direct children in PPTreeSubSet referring to this node
-	// XXX + [lo,hi) range this node is coming under in its parent	XXX -> in its tree ?
 }
 
 // Has returns whether node is in the set.
@@ -155,7 +154,7 @@ func normPath(path []zodb.Oid) []zodb.Oid {
 	return path
 }
 
-// ---- Union/Difference/Intersetctior ----
+// ---- Union/Difference/Intersection ----
 
 // Union returns U = PP(A.leafs | B.leafs)
 //
@@ -212,7 +211,7 @@ func (A PPTreeSubSet) DifferenceInplace(B PPTreeSubSet) {
 	A.xDifferenceInplace(B)
 }
 
-// XXX Intersection
+// TODO Intersection
 
 func (A PPTreeSubSet) xUnionInplace(B PPTreeSubSet) {
 	if tracePPSet {
@@ -333,7 +332,6 @@ func (S PPTreeSubSet) gc1(oid zodb.Oid) {
 	for oid != zodb.InvalidOid {
 		t := S[oid]
 		t.nchild--
-//		if t.nchild > 0 || /* root node */t.parent == zodb.InvalidOid {
 		if t.nchild > 0 {
 			break
 		}

wcfs/internal/xbtree/pptreesubset_test.go

@@ -88,6 +88,7 @@ func TestPPTreeSubSetOps(t *testing.T) {
 				S{}),				// D
 	}
 
+	// assert1 asserts that result of op(A,B) == resOK.
 	assert1 := func(op string, A, B, res, resOK S) {
 		t.Helper()
 		if res.Equal(resOK) {

wcfs/internal/xbtree/treediff.go

@@ -576,7 +576,7 @@ ABcov:
 	}
 
 	// {} oid -> nodeInRange for all nodes we've came through in Bv:
-	// current and previously expanded - up till top B
+	//                       current and previously expanded - up till top B.
 	BnodeIdx := map[zodb.Oid]*nodeInRange{}
 	if !Bempty {
 		BnodeIdx[ABoid] = btop
@@ -590,7 +590,7 @@ ABcov:
 	// by default a node contributes to δ-
 	// 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.keyrange == bc.keyrange
+	// - ac ∉ δZTC && ∃ bc from B: ac.oid == bc.oid && ac.keycov == bc.keycov
 	//   (ac+ac.children were not changed, ac stays in the tree with the same key range coverage)
 	Aq := []*nodeInRange{atop} // queue for A nodes that contribute to δ-
 	for len(Aq) > 0 {

wcfs/internal/xbtree/δbtail.go

@@ -33,10 +33,6 @@ import (
 	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/xtail"
 )
 
-// XXX malfancitioning rebuild currently breaks wcfs tests
-// TODO kill this after rebuild is finished
-const XXX_killWhenRebuildWorks = true
-
 const traceΔBtail = false
 const debugΔBtail = false
 
@@ -271,7 +267,7 @@ func (δBtail *ΔBtail) track(key Key, path []zodb.Oid) error {
 	// XXX locking
 
 	// first normalize path: remove embedded bucket and check if it was an
-	// empty artificial tree. We need to do the normalization becase we
+	// empty artificial tree. We need to do the normalization because we
 	// later check whether leaf path[-1] ∈ trackSet and without
 	// normalization path[-1] can be InvalidOid.
 	path = normPath(path)
@@ -375,10 +371,17 @@ func (δTtail *ΔTtail) rebuild(root zodb.Oid, δZtail *zodb.ΔTail, db *zodb.DB
 		}
 
 		// an iteration closer to tail may turn out to add a key to the tracking set.
-		// We have to recheck all entries newer that revision for changes to that key
+		// We have to recheck all entries newer that revision for changes to that key,
 		// for example:
 		//
-		//	XXX
+		//              8        5*
+		//             / \  <-  / \
+		//            2   8    2*  7
+		//
+		//     here initial tracked set is 5*-2*. Going to earlier revision
+		//     2'th keycov range is widen from [-∞,5) to [-∞,7), so 5*-7 in
+		//     later revision have to be rechecked because 7 was added into
+		//     tracking set.
 		//
 		// Implement this via restarting from head and cycling until
 		// set of tracked keys does not grow anymore.
@@ -602,22 +605,11 @@ func (δBtail *ΔBtail) _Update1(δZ *zodb.EventCommit) (δB1 _ΔBUpdate1, err e
 
 	δB1 = _ΔBUpdate1{ByRoot: make(map[zodb.Oid]*_ΔTUpdate1)}
 
-if XXX_killWhenRebuildWorks {
-// XXX hack - until vvv is reenabled
-	for root := range δBtail.trackNewRoots {
-		δTtail := δBtail.vδTbyRoot[root] // must succeed
-		δBtail.trackSet.UnionInplace(δTtail.trackNew)
-		δTtail.trackNew = PPTreeSubSet{}
-	}
-	δBtail.trackNewRoots = SetOid{}
-} else {
-// XXX reenable (currently breaks wcfs tests)
 	// update .trackSet and vδB from .trackNew
 	err = δBtail.rebuildAll()
 	if err != nil {
 		return δB1, err
 	}
-}
 
 	// XXX dup wrt rebuild?
 
@@ -666,7 +658,7 @@ if XXX_killWhenRebuildWorks {
 
 func (δBtail *ΔBtail) ForgetPast(revCut zodb.Tid) {
 	δBtail.δZtail.ForgetPast(revCut) // XXX stub
-	// TODO go throough vδBroots till revcut -> find which trees to trim -> trim ΔTtails.
+	// TODO go through vδBroots till revcut -> find which trees to trim -> trim ΔTtails.
 	panic("TODO")
 }
 

wcfs/internal/xbtree/δbtail_test.go

@@ -1154,9 +1154,6 @@ func assertΔTtail(t *testing.T, subj string, δbtail *ΔBtail, db *zodb.DB, tj
 		t0 = t0.prev
 	}
 	vδTok = vδTok_
-//	lo := t0.at
-//	hi := tj.at
-//	vδToid := δbtail.SliceByRootRev(treeRoot, lo, hi)
 	δTtail, ok := δbtail.vδTbyRoot[treeRoot]
 	var vδToid []ΔTree
 	if ok {
@@ -1166,7 +1163,6 @@ func assertΔTtail(t *testing.T, subj string, δbtail *ΔBtail, db *zodb.DB, tj
 	l = len(vδToid)
 	var vat []zodb.Tid
 	var vδT []map[Key]Δstring
-//	atPrev := lo
 	atPrev := t0.at
 	for _, δToid := range vδToid {
 		vat = append(vat, δToid.Rev)