[#1445] metabase/test: Add test for graves of the new format

Test iterating over graveyard populated with graves of both old and
new formats, i. e. without and with an expiration epoch, respectively.

Signed-off-by: Aleksey Savchuk <a.savchuk@yadro.com>

pkg/local_object_storage/metabase/graveyard_test.go

@@ -14,6 +14,7 @@ import (
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	oidtest "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id/test"
 	"github.com/stretchr/testify/require"
+	"golang.org/x/sync/errgroup"
 )
 
 func TestDB_IterateDeletedObjects_EmptyDB(t *testing.T) {
@@ -465,3 +466,67 @@ func TestDB_InhumeTombstones(t *testing.T) {
 	require.NoError(t, err)
 	require.Zero(t, counter)
 }
+
+func TestIterateOverGraveyardWithDifferentGraveFormats(t *testing.T) {
+	t.Parallel()
+
+	type grave struct {
+		addr, tomb oid.Address
+		expEpoch   uint64
+	}
+
+	var (
+		numGraves = 20
+
+		expectedGraves []grave
+		actualGraves   []grave
+		eg             errgroup.Group
+	)
+
+	db := newDB(t)
+	defer func() { require.NoError(t, db.Close(context.Background())) }()
+
+	var expEpochs []uint64
+	for range numGraves / 2 {
+		expEpochs = append(expEpochs, rand.Uint64())
+		expEpochs = append(expEpochs, meta.NoExpirationEpoch)
+	}
+	rand.Shuffle(len(expEpochs), func(i, j int) {
+		expEpochs[i], expEpochs[j] = expEpochs[j], expEpochs[i]
+	})
+
+	for _, expEpoch := range expEpochs {
+		cnt := cidtest.ID()
+
+		addr := oidtest.Address()
+		addr.SetContainer(cnt)
+
+		tomb := oidtest.Address()
+		tomb.SetContainer(cnt)
+
+		expectedGraves = append(expectedGraves, grave{
+			addr: addr, tomb: tomb, expEpoch: expEpoch,
+		})
+
+		eg.Go(func() error {
+			var prm meta.InhumePrm
+			prm.SetAddresses(addr)
+			prm.SetTombstoneAddress(tomb, expEpoch)
+
+			_, err := db.Inhume(context.Background(), prm)
+			return err
+		})
+	}
+	require.NoError(t, eg.Wait())
+
+	var iterPrm meta.GraveyardIterationPrm
+	iterPrm.SetHandler(func(o meta.TombstonedObject) error {
+		actualGraves = append(actualGraves, grave{
+			o.Address(), o.Tombstone(), o.ExpirationEpoch(),
+		})
+		return nil
+	})
+	require.NoError(t, db.IterateOverGraveyard(context.Background(), iterPrm))
+
+	require.ElementsMatch(t, expectedGraves, actualGraves)
+}