Apply suggestions from code review

Author: mmsqe

x/auth/keeper/keeper.go

@@ -183,7 +183,7 @@ func (ak AccountKeeper) GetSequence(ctx context.Context, addr sdk.AccAddress) (u
 	return acc.GetSequence(), nil
 }
 
-func (ak AccountKeeper) GetAccountNumberLegacy(ctx context.Context) (uint64, error) {
+func (ak AccountKeeper) getAccountNumberLegacy(ctx context.Context) (uint64, error) {
 	store := ak.storeService.OpenKVStore(ctx)
 	b, err := store.Get(types.LegacyGlobalAccountNumberKey)
 	if err != nil {
@@ -196,6 +196,16 @@ func (ak AccountKeeper) GetAccountNumberLegacy(ctx context.Context) (uint64, err
 	return v.Value, nil
 }
 
+func (ak AccountKeeper) SetAccountNumberLegacy(ctx context.Context, num uint64) error {
+	store := ak.storeService.OpenKVStore(ctx)
+	legacyValue := gogotypes.UInt64Value{Value: num}
+	bz, err := legacyValue.Marshal()
+	if err != nil {
+		return err
+	}
+	return store.Set(types.LegacyGlobalAccountNumberKey, bz)
+}
+
 // NextAccountNumber returns and increments the global account number counter.
 // If the global account number is not set, it initializes it with value 0.
 func (ak AccountKeeper) NextAccountNumber(ctx context.Context) uint64 {
@@ -204,7 +214,7 @@ func (ak AccountKeeper) NextAccountNumber(ctx context.Context) uint64 {
 		// this won't happen in the tip of production network,
 		// but can happen when query historical states,
 		// fallback to old key for backward-compatibility.
-		n, err = ak.GetAccountNumberLegacy(ctx)
+		n, err = ak.getAccountNumberLegacy(ctx)
 	}
 
 	if err != nil {

x/auth/keeper/keeper_test.go

@@ -215,3 +215,21 @@ func (suite *KeeperTestSuite) TestInitGenesis() {
 	// we expect nextNum to be 2 because we initialize fee_collector as account number 1
 	suite.Require().Equal(2, int(nextNum))
 }
+
+func (suite *KeeperTestSuite) TestNextAccountNumber() {
+	ctx := suite.ctx
+	legacyNum := uint64(100)
+	err := suite.accountKeeper.SetAccountNumberLegacy(ctx, legacyNum)
+	suite.Require().NoError(err)
+
+	newAccountNumber := uint64(200)
+	err = suite.accountKeeper.AccountNumber.Set(ctx, newAccountNumber)
+	suite.Require().NoError(err)
+
+	nextNum := suite.accountKeeper.NextAccountNumber(ctx)
+	suite.Require().Equal(int(newAccountNumber), int(nextNum))
+
+	nextNum = suite.accountKeeper.NextAccountNumber(ctx)
+	suite.Require().Equal(int(newAccountNumber+1), int(nextNum))
+	suite.Require().NotEqual(int(legacyNum), int(nextNum))
+}