.

wcfs/internal/xbtree/δbtail.go

@@ -237,6 +237,7 @@ func (btail *ΔTail) Update(δZ *zodb.EventCommit) []ΔTree {
 // XXX only tracked set?
 //
 // XXX at must ∈ (tail, head]	XXX [tail ?
+// XXX key must be tracked?
 func (btail *ΔTail) GetAt(root *Tree, key Key, at zodb.Tid) (value Value, ok bool, rev zodb.Tid, revExact bool) {
 	panic("TODO")
 }

wcfs/wcfs.go

@@ -749,7 +749,7 @@ retry:
 		default:
 			continue // object not related to any bigfile
 
-		// XXX kill Tree/Bucket here
+		// XXX kill Tree/Bucket here (-> ΔFtail)
 		case *btree.LOBTree:
 			btreeChangev = append(btreeChangev, obj.POid())
 
@@ -1288,7 +1288,7 @@ func (w *Watch) pin(ctx context.Context, blk int64, rev zodb.Tid) (err error) {
 	return nil
 }
 
-// pinIfNewer make sure that file[blk] on client side stays as of @w.at state.
+// pinIfNewer makes sure that file[blk] on client side stays as of @w.at state.
 //
 // rev is blk revision as of head. If rev > w.at the block is pinned on client side.
 func (w *Watch) pinIfNewer(ctx context.Context, blk int64, rev zodb.Tid) error {
@@ -1349,14 +1349,10 @@ func (wlink *WatchLink) setupWatch(ctx context.Context, foid zodb.Oid, at zodb.T
 	toPin := map[int64]zodb.Tid{} // blk -> @rev
 
 /* XXX reenable
-	// XXX f.δtail.Head() not neccessarily = head.At()
-	// (if f was not changed by a txn, f.δtail stays not updated)	XXX correct?
-	//
+
 	// FIXME (!!!) since f.δtail does not have all changes to f, here we
 	// can be missing some pins we should be sending. (see wcfs_test.py for details)
-	//
-	// XXX at can be > f.δtail.Head due to ^^^ (and then SliceByRev panics)
-	for _, δ := range f.δtail.SliceByRev(at, f.δtail.Head()) {
+	for _, δ := range δFtail.SliceByRev(f, at, f.δtail.Head()) {
 		for _, blk := range δ.Changev {
 			_, already := toPin[blk]
 			if already {

wcfs/δftail.go

@@ -120,6 +120,7 @@ func (δf *ΔFTail) LastRevOf(file *BigFile, blk int64, at zodb.Tid) (_ zodb.Tid
 // if exact=False - what is returned is only an upper bound for last block revision.
 //
 // at must ∈ (tail, head]	XXX [tail ?
+// XXX blk must be tracked?
 func (f *BigFile) LastBlkRev(blk int64, at zodb.Tid) (_ zodb.Tid, exact bool) {
 	δf := f.head.bfdir.δFtail