index: additional tests for new index save methods

internal/index/master_index_test.go

@@ -355,6 +355,25 @@ func TestIndexSave(t *testing.T) {
 }
 
 func testIndexSave(t *testing.T, version uint) {
+	for _, test := range []struct {
+		name  string
+		saver func(idx *index.MasterIndex, repo restic.Repository) error
+	}{
+		{"rewrite no-op", func(idx *index.MasterIndex, repo restic.Repository) error {
+			return idx.Rewrite(context.TODO(), repo, nil, nil, nil, index.MasterIndexRewriteOpts{})
+		}},
+		{"rewrite skip-all", func(idx *index.MasterIndex, repo restic.Repository) error {
+			return idx.Rewrite(context.TODO(), repo, nil, restic.NewIDSet(), nil, index.MasterIndexRewriteOpts{})
+		}},
+		{"SaveFallback", func(idx *index.MasterIndex, repo restic.Repository) error {
+			err := restic.ParallelRemove(context.TODO(), repo, idx.IDs(), restic.IndexFile, nil, nil)
+			if err != nil {
+				return nil
+			}
+			return idx.SaveFallback(context.TODO(), repo, restic.NewIDSet(), nil)
+		}},
+	} {
+		t.Run(test.name, func(t *testing.T) {
 			repo := createFilledRepo(t, 3, version)
 
 			idx := index.NewMasterIndex()
@@ -364,7 +383,7 @@ func testIndexSave(t *testing.T, version uint) {
 				blobs[pb] = struct{}{}
 			}))
 
-	rtest.OK(t, idx.Rewrite(context.TODO(), repo, nil, nil, nil, index.MasterIndexRewriteOpts{}))
+			rtest.OK(t, test.saver(idx, repo))
 			idx = index.NewMasterIndex()
 			rtest.OK(t, idx.Load(context.TODO(), repo, nil, nil))
 
@@ -378,4 +397,60 @@ func testIndexSave(t *testing.T, version uint) {
 			rtest.Equals(t, 0, len(blobs), "saved index is missing blobs")
 
 			checker.TestCheckRepo(t, repo, false)
+		})
+	}
+}
+
+func TestIndexSavePartial(t *testing.T) {
+	repository.TestAllVersions(t, testIndexSavePartial)
+}
+
+func testIndexSavePartial(t *testing.T, version uint) {
+	repo := createFilledRepo(t, 3, version)
+
+	// capture blob list before adding fourth snapshot
+	idx := index.NewMasterIndex()
+	rtest.OK(t, idx.Load(context.TODO(), repo, nil, nil))
+	blobs := make(map[restic.PackedBlob]struct{})
+	rtest.OK(t, idx.Each(context.TODO(), func(pb restic.PackedBlob) {
+		blobs[pb] = struct{}{}
+	}))
+
+	// add+remove new snapshot and track its pack files
+	packsBefore := listPacks(t, repo)
+	sn := restic.TestCreateSnapshot(t, repo, snapshotTime.Add(time.Duration(4)*time.Second), depth)
+	rtest.OK(t, repo.RemoveUnpacked(context.TODO(), restic.SnapshotFile, *sn.ID()))
+	packsAfter := listPacks(t, repo)
+	newPacks := packsAfter.Sub(packsBefore)
+
+	// rewrite index and remove pack files of new snapshot
+	idx = index.NewMasterIndex()
+	rtest.OK(t, idx.Load(context.TODO(), repo, nil, nil))
+	rtest.OK(t, idx.Rewrite(context.TODO(), repo, newPacks, nil, nil, index.MasterIndexRewriteOpts{}))
+
+	// check blobs
+	idx = index.NewMasterIndex()
+	rtest.OK(t, idx.Load(context.TODO(), repo, nil, nil))
+	rtest.OK(t, idx.Each(context.TODO(), func(pb restic.PackedBlob) {
+		if _, ok := blobs[pb]; ok {
+			delete(blobs, pb)
+		} else {
+			t.Fatalf("unexpected blobs %v", pb)
+		}
+	}))
+	rtest.Equals(t, 0, len(blobs), "saved index is missing blobs")
+
+	// remove pack files to make check happy
+	rtest.OK(t, restic.ParallelRemove(context.TODO(), repo, newPacks, restic.PackFile, nil, nil))
+
+	checker.TestCheckRepo(t, repo, false)
+}
+
+func listPacks(t testing.TB, repo restic.Lister) restic.IDSet {
+	s := restic.NewIDSet()
+	rtest.OK(t, repo.List(context.TODO(), restic.PackFile, func(id restic.ID, _ int64) error {
+		s.Insert(id)
+		return nil
+	}))
+	return s
 }