more loc but safer

immutable_tree.go

@@ -301,7 +301,7 @@ func (t *ImmutableTree) IsFastCacheEnabled() (bool, error) {
 }
 
 func (t *ImmutableTree) isLatestTreeVersion() (bool, error) {
-	latestVersion, err := t.ndb.getLatestVersion()
+	_, latestVersion, err := t.ndb.getLatestVersion()
 	if err != nil {
 		return false, err
 	}

iterator_test.go

@@ -182,7 +182,7 @@ func TestIterator_WithDelete_Full_Ascending_Success(t *testing.T) {
 	err = tree.DeleteVersionsTo(1)
 	require.NoError(t, err)
 
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	immutableTree, err := tree.GetImmutable(latestVersion)
 	require.NoError(t, err)
@@ -253,7 +253,7 @@ func setupIteratorAndMirror(t *testing.T, config *iteratorTestConfig) (corestore
 	_, _, err := tree.SaveVersion()
 	require.NoError(t, err)
 
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	immutableTree, err := tree.GetImmutable(latestVersion)
 	require.NoError(t, err)

migrate_test.go

@@ -177,7 +177,7 @@ func TestDeleteVersions(t *testing.T) {
 	// Test LoadVersionForOverwriting for the legacy version
 	err = tree.LoadVersionForOverwriting(int64(targetVersion))
 	require.NoError(t, err)
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	require.Equal(t, int64(targetVersion), latestVersion)
 	legacyLatestVersion, err := tree.ndb.getLegacyLatestVersion()

mutable_tree.go

@@ -75,7 +75,8 @@ func (tree *MutableTree) IsEmpty() bool {
 
 // GetLatestVersion returns the latest version of the tree.
 func (tree *MutableTree) GetLatestVersion() (int64, error) {
-	return tree.ndb.getLatestVersion()
+	_, v, err := tree.ndb.getLatestVersion()
+	return v, err
 }
 
 // VersionExists returns whether or not a version exists.
@@ -92,10 +93,13 @@ func (tree *MutableTree) VersionExists(version int64) bool {
 	if err != nil {
 		return false
 	}
-	latestVersion, err := tree.ndb.getLatestVersion()
+	found, latestVersion, err := tree.ndb.getLatestVersion()
 	if err != nil {
 		return false
 	}
+	if !found {
+		return false
+	}
 
 	return firstVersion <= version && version <= latestVersion
 }
@@ -106,7 +110,7 @@ func (tree *MutableTree) AvailableVersions() []int {
 	if err != nil {
 		return nil
 	}
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	if err != nil {
 		return nil
 	}
@@ -452,7 +456,7 @@ func (tree *MutableTree) LoadVersion(targetVersion int64) (int64, error) {
 			tree.ndb.opts.InitialVersion, firstVersion)
 	}
 
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	if err != nil {
 		return 0, err
 	}
@@ -552,7 +556,8 @@ func (tree *MutableTree) IsUpgradeable() (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	return !tree.skipFastStorageUpgrade && (!tree.ndb.hasUpgradedToFastStorage() || shouldForce), nil
+	hasUpgradedToFastStorage := tree.ndb.hasUpgradedToFastStorage()
+	return !tree.skipFastStorageUpgrade && (!hasUpgradedToFastStorage || shouldForce), nil
 }
 
 // enableFastStorageAndCommitIfNotEnabled if nodeDB doesn't mark fast storage as enabled, enable it, and commit the update.
@@ -607,7 +612,7 @@ func (tree *MutableTree) enableFastStorageAndCommit() error {
 		return err
 	}
 
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	if err != nil {
 		return err
 	}

mutable_tree_test.go

@@ -769,6 +769,8 @@ func TestUpgradeStorageToFast_LatestVersion_Success(t *testing.T) {
 	require.False(t, isUpgradeable)
 	require.NoError(t, err)
 
+	_, _, err = tree.SaveVersion()
+	require.NoError(t, err)
 	isFastCacheEnabled, err = tree.IsFastCacheEnabled()
 	require.NoError(t, err)
 	require.True(t, isFastCacheEnabled)
@@ -907,7 +909,7 @@ func TestFastStorageReUpgradeProtection_NoForceUpgrade_Success(t *testing.T) {
 
 	// Pretend that we called Load and have the latest state in the tree
 	tree.version = latestTreeVersion
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	require.Equal(t, latestVersion, int64(latestTreeVersion))
 
@@ -1001,7 +1003,7 @@ func TestFastStorageReUpgradeProtection_ForceUpgradeFirstTime_NoForceSecondTime_
 
 	// Pretend that we called Load and have the latest state in the tree
 	tree.version = latestTreeVersion
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	require.Equal(t, latestVersion, int64(latestTreeVersion))
 
@@ -1479,3 +1481,16 @@ func TestMutableTreeClose(t *testing.T) {
 
 	require.NoError(t, tree.Close())
 }
+
+func TestMutableTree_InitialVersionZero(t *testing.T) {
+	db := dbm.NewMemDB()
+
+	tree := NewMutableTree(db, 0, false, NewNopLogger(), InitialVersionOption(0))
+
+	_, err := tree.Set([]byte("hello"), []byte("world"))
+	require.NoError(t, err)
+
+	_, version, err := tree.SaveVersion()
+	require.NoError(t, err)
+	require.Equal(t, int64(0), version)
+}

nodedb.go

@@ -305,6 +305,11 @@ func (ndb *nodeDB) SetFastStorageVersionToBatch(latestVersion int64) error {
 		newVersion = fastStorageVersionValue
 	}
 
+	// no latest version found
+	// if latestVersion == -1 {
+	// use initial version
+	// latestVersion = int64(ndb.opts.InitialVersion)
+	// }
 	newVersion += fastStorageVersionDelimiter + strconv.Itoa(int(latestVersion))
 
 	if err := ndb.batch.Set(metadataKeyFormat.Key([]byte(storageVersionKey)), []byte(newVersion)); err != nil {
@@ -331,7 +336,7 @@ func (ndb *nodeDB) shouldForceFastStorageUpgrade() (bool, error) {
 	versions := strings.Split(ndb.storageVersion, fastStorageVersionDelimiter)
 
 	if len(versions) == 2 {
-		latestVersion, err := ndb.getLatestVersion()
+		_, latestVersion, err := ndb.getLatestVersion()
 		if err != nil {
 			// TODO: should be true or false as default? (removed panic here)
 			return false, err
@@ -525,7 +530,7 @@ func (ndb *nodeDB) deleteLegacyVersions(legacyLatestVersion int64) error {
 
 // DeleteVersionsFrom permanently deletes all tree versions from the given version upwards.
 func (ndb *nodeDB) DeleteVersionsFrom(fromVersion int64) error {
-	latest, err := ndb.getLatestVersion()
+	_, latest, err := ndb.getLatestVersion()
 	if err != nil {
 		return err
 	}
@@ -642,7 +647,7 @@ func (ndb *nodeDB) deleteVersionsTo(toVersion int64) error {
 		return err
 	}
 
-	latest, err := ndb.getLatestVersion()
+	_, latest, err := ndb.getLatestVersion()
 	if err != nil {
 		return err
 	}
@@ -727,7 +732,7 @@ func (ndb *nodeDB) getFirstVersion() (int64, error) {
 		return version, nil
 	}
 	// Find the first version
-	latestVersion, err := ndb.getLatestVersion()
+	_, latestVersion, err := ndb.getLatestVersion()
 	if err != nil {
 		return 0, err
 	}
@@ -797,21 +802,21 @@ func (ndb *nodeDB) resetLegacyLatestVersion(version int64) {
 	ndb.legacyLatestVersion = version
 }
 
-func (ndb *nodeDB) getLatestVersion() (int64, error) {
+func (ndb *nodeDB) getLatestVersion() (bool, int64, error) {
 	ndb.mtx.Lock()
 	latestVersion := ndb.latestVersion
 	ndb.mtx.Unlock()
 
 	if latestVersion > 0 {
-		return latestVersion, nil
+		return true, latestVersion, nil
 	}
 
 	itr, err := ndb.db.ReverseIterator(
 		nodeKeyPrefixFormat.KeyInt64(int64(1)),
 		nodeKeyPrefixFormat.KeyInt64(int64(math.MaxInt64)),
 	)
 	if err != nil {
-		return 0, err
+		return false, 0, err
 	}
 	defer itr.Close()
 
@@ -821,24 +826,25 @@ func (ndb *nodeDB) getLatestVersion() (int64, error) {
 		nodeKeyFormat.Scan(k, &nk)
 		latestVersion = GetNodeKey(nk).version
 		ndb.resetLatestVersion(latestVersion)
-		return latestVersion, nil
+		return true, latestVersion, nil
 	}
 
 	if err := itr.Error(); err != nil {
-		return 0, err
+		return false, 0, err
 	}
 
 	// If there are no versions, try to get the latest version from the legacy format.
 	latestVersion, err = ndb.getLegacyLatestVersion()
 	if err != nil {
-		return 0, err
+		return false, 0, err
 	}
 	if latestVersion > 0 {
 		ndb.resetLatestVersion(latestVersion)
-		return latestVersion, nil
+		return true, latestVersion, nil
 	}
 
-	return -1, nil
+	return false, 0, nil
+	// return -1, nil
 }
 
 func (ndb *nodeDB) resetLatestVersion(version int64) {
@@ -1246,7 +1252,7 @@ func (ndb *nodeDB) traverseStateChanges(startVersion, endVersion int64, fn func(
 	if startVersion < firstVersion {
 		startVersion = firstVersion
 	}
-	latestVersion, err := ndb.getLatestVersion()
+	_, latestVersion, err := ndb.getLatestVersion()
 	if err != nil {
 		return err
 	}

nodedb_test.go

@@ -87,7 +87,7 @@ func TestSetStorageVersion_Success(t *testing.T) {
 	ndb := newNodeDB(db, 0, DefaultOptions(), NewNopLogger())
 	require.Equal(t, defaultStorageVersionValue, ndb.getStorageVersion())
 
-	latestVersion, err := ndb.getLatestVersion()
+	_, latestVersion, err := ndb.getLatestVersion()
 	require.NoError(t, err)
 
 	err = ndb.SetFastStorageVersionToBatch(latestVersion)
@@ -404,7 +404,7 @@ func TestDeleteVersionsFromNoDeadlock(t *testing.T) {
 	err := ndb.SetFastStorageVersionToBatch(ndb.latestVersion)
 	require.NoError(t, err)
 
-	latestVersion, err := ndb.getLatestVersion()
+	_, latestVersion, err := ndb.getLatestVersion()
 	require.NoError(t, err)
 	require.Equal(t, expectedVersion+fastStorageVersionDelimiter+strconv.Itoa(int(latestVersion)), ndb.getStorageVersion())
 	require.NoError(t, ndb.batch.Write())

tree_random_test.go

@@ -283,7 +283,7 @@ func assertEmptyDatabase(t *testing.T, tree *MutableTree) {
 
 	storageVersionValue, err := tree.ndb.db.Get([]byte(firstKey))
 	require.NoError(t, err)
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	require.Equal(t, fastStorageVersionValue+fastStorageVersionDelimiter+strconv.Itoa(int(latestVersion)), string(storageVersionValue))
 
@@ -347,7 +347,7 @@ func assertMirror(t *testing.T, tree *MutableTree, mirror map[string]string, ver
 
 // Checks that fast node cache matches live state.
 func assertFastNodeCacheIsLive(t *testing.T, tree *MutableTree, mirror map[string]string, version int64) {
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	if latestVersion != version {
 		// The fast node cache check should only be done to the latest version
@@ -364,7 +364,7 @@ func assertFastNodeCacheIsLive(t *testing.T, tree *MutableTree, mirror map[strin
 
 // Checks that fast nodes on disk match live state.
 func assertFastNodeDiskIsLive(t *testing.T, tree *MutableTree, mirror map[string]string, version int64) {
-	latestVersion, err := tree.ndb.getLatestVersion()
+	_, latestVersion, err := tree.ndb.getLatestVersion()
 	require.NoError(t, err)
 	if latestVersion != version {
 		// The fast node disk check should only be done to the latest version