.

wcfs/internal/xbtree/δbtail.go

@@ -89,13 +89,14 @@ type Value  = zodb.Oid // XXX assumes key points to IPersistent
 // It covers changes to keys from tracked subset of BTrees parts and
 // semantically consists of
 //
-//	# k/v change history		; rev ∈ (tail, head]
-//	[](rev↑,
-//	    [](root,
-//	        {}(key, value)))
+//	# trees changed by a revision
+//	[](rev↑, []root)		; rev ∈ (tail, head]
 //
-//	# set of k/v @tail for keys that are not changed in (tail, head].
 //	{} root ->
+//		# k/v change history	; rev ∈ (tail, head]
+//		[](rev↑, {}(key, value))
+//
+//		# set of k/v @tail for keys changed in (tail, head].
 //		{}(key, value)
 //
 // A tree nodes become tracked via Track(path) request.
@@ -111,11 +112,10 @@ type Value  = zodb.Oid // XXX assumes key points to IPersistent
 //
 // ΔTail is not safe for concurrent access.
 type ΔTail struct {
-	δBtail []ΔRevEntry // BTree changes; Covers keys ∈ tracket subset
-	δZtail *zodb.ΔTail // raw ZODB changes; Kept to rebuild δBtail after new Track
+	δZtail *zodb.ΔTail // raw ZODB changes; Kept to rebuild δBtail (XXX) after new Track
 
-	// {} root -> {}k/v @tail for keys that are not changed in (tail, head].
-	atTail map[*Tree]map[Key]Value
+	δBtail []ΔRevEntry // which BTree were changed; Noted only by keys ∈ tracket subset
+	byRoot map[*Tree]*ΔTreeTail
 
 	// XXX or ask client provide db on every call?
 	db     *zodb.DB    // to open connections to load new/old tree|buckets
@@ -130,10 +130,26 @@ type ΔTail struct {
 	lastRevOf map[zodb.Oid]map[Key]zodb.Tid // {} root -> {} key -> last
 }
 
-// ΔRevEntry represents information about BTrees changes in one revision.
+// ΔTreeTail represent tail of revisional changes to one BTree.
+//
+// See ΔTail documentation for details.
+type ΔTreeTail struct {
+	δTtail []ΔTreeEntry // changes to tree keys; covers keys ∈ tracket subset
+
+	// {}k/v @tail for keys that are changed in (tail, head].
+	atTail map[*Tree]map[Key]Value
+}
+
+// ΔRevEntry describes which BTrees were change in one revision.
 type ΔRevEntry struct {
 	Rev     zodb.Tid
-	Changev []ΔTree
+	Changev []Tree	// root XXX -> Oid?
+}
+
+// ΔTreeEntry describes BTree changes due to one revision.
+type ΔTreeEntry struct {
+	Rev    zodb.Tid
+	Change map[Key]Value
 }
 
 // ΔTree represents changes to one tree.

wcfs/wcfs_test.py

@@ -648,6 +648,9 @@ def test_wcfs():
     # XXX pin message when blk data only first appeared after > w.at - pin
     # needs to pin to zero.
 
+    # XXX ZBlk copied from blk1 -> blk2 ; for the same file and for file1 -> file2
+    # XXX ZBlk moved  from blk1 -> blk2 ; for the same file and for file1 -> file2
+
 
 
 def test_wcfs_invproto():