.

wcfs/internal/xbtree/treediff.go

@@ -453,8 +453,8 @@ func diffX(ctx context.Context, a, b Node, δZTC setOid, trackSet blib.PPTreeSub
 // a, b point to top of subtrees @old and @new revisions.
 // δZTC is connected set of objects covering δZT (objects changed in this tree in old..new).
 func diffT(ctx context.Context, A, B *Tree, δZTC setOid, trackSet blib.PPTreeSubSet) (δ map[Key]ΔValue, δtrack *blib.ΔPPTreeSubSet, δtkeycov *blib.RangedKeySet, err error) {
-	tracefDiff("  diffT %s %s\n", xidOf(A), xidOf(B))
-	defer xerr.Contextf(&err, "diffT %s %s", xidOf(A), xidOf(B))
+	tracefDiff("  diffT %s %s\n", xzodb.XidOf(A), xzodb.XidOf(B))
+	defer xerr.Contextf(&err, "diffT %s %s", xzodb.XidOf(A), xzodb.XidOf(B))
 
 	δ = map[Key]ΔValue{}
 	δtrack = blib.NewΔPPTreeSubSet()
@@ -887,8 +887,8 @@ func δMerge(δ, δ2 map[Key]ΔValue) error {
 // diffB computes difference in between two buckets.
 // see diffX for details.
 func diffB(ctx context.Context, a, b *Bucket) (δ map[Key]ΔValue, err error) {
-	tracefDiff("  diffB %s %s\n", xidOf(a), xidOf(b))
-	defer xerr.Contextf(&err, "diffB %s %s", xidOf(a), xidOf(b))
+	tracefDiff("  diffB %s %s\n", xzodb.XidOf(a), xzodb.XidOf(b))
+	defer xerr.Contextf(&err, "diffB %s %s", xzodb.XidOf(a), xzodb.XidOf(b))
 	// XXX oid can be InvalidOid for T/B... (i.e. B is part of T and is not yet committed separately)
 
 	var av []BucketEntry
@@ -976,15 +976,6 @@ func vOid(xvalue interface{}) (zodb.Oid, error) {
 	return value.POid(), nil
 }
 
-// xidOf return string representation of object xid.
-func xidOf(obj zodb.IPersistent) string {
-	if obj == nil || reflect.ValueOf(obj).IsNil() {
-		return "ø"
-	}
-	xid := zodb.Xid{At: obj.PJar().At(), Oid: obj.POid()}
-	return xid.String()
-}
-
 func (rn *nodeInRange) String() string {
 	done := " ";   if rn.done         { done = "*" }
 	return fmt.Sprintf("%s%s%s", done, rn.keycov, vnode(rn.node))

wcfs/internal/xzodb/xzodb.go

@@ -24,6 +24,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"reflect"
 
 	"lab.nexedi.com/kirr/go123/xcontext"
 	"lab.nexedi.com/kirr/go123/xerr"
@@ -124,3 +125,12 @@ func IsErrNoData(err error) bool {
 		return false
 	}
 }
+
+// XidOf return string representation of object xid.
+func XidOf(obj zodb.IPersistent) string {
+	if obj == nil || reflect.ValueOf(obj).IsNil() {
+		return "ø"
+	}
+	xid := zodb.Xid{At: obj.PJar().At(), Oid: obj.POid()}
+	return xid.String()
+}

wcfs/internal/zdata/δftail.go

@@ -30,7 +30,7 @@ import (
 	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/set"
 	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/xbtree"
 	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/xtail"
-//	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/xzodb"
+	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/xzodb"
 )
 
 type setI64 = set.I64
@@ -510,13 +510,13 @@ func (δFtail *ΔFtail) LastBlkRev(ctx context.Context, zf *ZBigFile, blk int64,
 
 
 
-// diffF computes direct differece in between two ZBigFiles.
+// diffF computes direct differece in between two ZBigFile objects.
 type _ΔZBigFile struct {
 	blksizeOld, blksizeNew int64
 	blktabOld,  blktabNew  zodb.Oid
 }
 func diffF(ctx context.Context, a, b *ZBigFile) (δ *_ΔZBigFile, err error) {
-	defer xerr.Contextf(&err, "diffF %s %s", xidOf(a), xidOf(b))
+	defer xerr.Contextf(&err, "diffF %s %s", xzodb.XidOf(a), xzodb.XidOf(b))
 
 	δ = &_ΔZBigFile{}
 	if a == nil {
@@ -539,5 +539,6 @@ func diffF(ctx context.Context, a, b *ZBigFile) (δ *_ΔZBigFile, err error) {
 		δ.blktabNew  = b.blktab.POid()
 	}
 
+	// XXX return δ=nil if no change?
 	return δ, nil
 }