WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) error

	// Metadata operations
	DeleteVersion(ctx context.Context, volume, path string, fi FileInfo, forceDelMarker bool, opts DeleteOptions) error
	DeleteVersions(ctx context.Context, volume string, versions []FileInfoVersions, opts DeleteOptions) []error
	DeleteBulk(ctx context.Context, volume string, paths ...string) error

	fatalErr(xl.AddVersion(tierfi))
	report()
	tierfi.TransitionStatus = lifecycle.TransitionComplete
	tierfi.TransitionedObjName = mustGetUUID()
	tierfi.TransitionTier = "MINIOTIER-1"
	var err error
	_, err = xl.DeleteVersion(tierfi)
	fatalErr(err)
	report()

	fvIDs := []string{
		"00000000-0000-0000-0000-0000000000f1",
		"00000000-0000-0000-0000-0000000000f2",
	}
	// Simulate overwrite of null version

			transfi.TransitionStatus = lifecycle.TransitionComplete
			transfi.TransitionTier = "MINIO-TIER"
			transfi.TransitionedObjName = mustGetUUID()
			xl.DeleteVersion(transfi)

			fi.SetTierFreeVersionID(mustGetUUID())
			// delete this version leading to a free version
			xl.DeleteVersion(fi)
			freeVersionIDs = append(freeVersionIDs, fi.TierFreeVersionID())
			allVersionIDs = append(allVersionIDs, fi.TierFreeVersionID())
		} else {