add tests

types/query/filtered_pagination.go

@@ -29,6 +29,7 @@ func FilteredPaginate(
 	key := pageRequest.Key
 	limit := pageRequest.Limit
 	countTotal := pageRequest.CountTotal
+	reverse := pageRequest.Reverse
 
 	if offset > 0 && key != nil {
 		return nil, fmt.Errorf("invalid request, either offset or key is expected, got both")
@@ -42,15 +43,20 @@ func FilteredPaginate(
 	}
 
 	if len(key) != 0 {
-		iterator := getIterator(prefixStore, key, nil, pageRequest.Reverse)
+		iterator := getIterator(prefixStore, key, nil, reverse)
 		defer iterator.Close()
 
 		var numHits uint64
 		var nextKey []byte
 
 		for ; iterator.Valid(); iterator.Next() {
-			if numHits == limit {
+			if numHits == limit-1 && reverse {
 				nextKey = iterator.Key()
+			}
+			if numHits == limit {
+				if !reverse {
+					nextKey = iterator.Key()
+				}
 				break
 			}
 
@@ -73,7 +79,7 @@ func FilteredPaginate(
 		}, nil
 	}
 
-	iterator := getIterator(prefixStore, nil, nil, pageRequest.Reverse)
+	iterator := getIterator(prefixStore, nil, nil, reverse)
 	defer iterator.Close()
 
 	end := offset + limit

types/query/filtered_pagination_test.go

@@ -89,6 +89,88 @@ func (s *paginationTestSuite) TestFilteredPaginations() {
 	s.Require().LessOrEqual(len(balances), 2)
 }
 
+func (s *paginationTestSuite) TestReverseFilteredPaginations() {
+	app, ctx, appCodec := setupTest()
+
+	var balances sdk.Coins
+	for i := 0; i < numBalances; i++ {
+		denom := fmt.Sprintf("foo%ddenom", i)
+		balances = append(balances, sdk.NewInt64Coin(denom, 100))
+	}
+
+	for i := 0; i < 10; i++ {
+		denom := fmt.Sprintf("test%ddenom", i)
+		balances = append(balances, sdk.NewInt64Coin(denom, 250))
+	}
+
+	balances = balances.Sort()
+	addr1 := sdk.AccAddress([]byte("addr1"))
+	acc1 := app.AccountKeeper.NewAccountWithAddress(ctx, addr1)
+	app.AccountKeeper.SetAccount(ctx, acc1)
+	s.Require().NoError(simapp.FundAccount(app, ctx, addr1, balances))
+	store := ctx.KVStore(app.GetKey(types.StoreKey))
+
+	// verify pagination with limit > total values
+	pageReq := &query.PageRequest{Key: nil, Limit: 5, CountTotal: true, Reverse: true}
+	balns, res, err := execFilterPaginate(store, pageReq, appCodec)
+	s.Require().NoError(err)
+	s.Require().NotNil(res)
+	s.Require().Equal(5, len(balns))
+
+	s.T().Log("verify empty request")
+	balns, res, err = execFilterPaginate(store, nil, appCodec)
+	s.Require().NoError(err)
+	s.Require().NotNil(res)
+	s.Require().Equal(10, len(balns))
+	s.Require().Equal(uint64(10), res.Total)
+	s.Require().Nil(res.NextKey)
+
+	s.T().Log("verify default limit")
+	pageReq = &query.PageRequest{Key: nil, Limit: 0, Reverse: true}
+	balns, res, err = execFilterPaginate(store, pageReq, appCodec)
+	s.Require().NoError(err)
+	s.Require().NotNil(res)
+	s.Require().Equal(10, len(balns))
+	s.Require().Equal(uint64(10), res.Total)
+
+	s.T().Log("verify nextKey is returned if there are more results")
+	pageReq = &query.PageRequest{Key: nil, Limit: 2, CountTotal: true, Reverse: true}
+	balns, res, err = execFilterPaginate(store, pageReq, appCodec)
+	s.Require().NoError(err)
+	s.Require().NotNil(res)
+	s.Require().Equal(2, len(balns))
+	s.Require().NotNil(res.NextKey)
+	s.Require().Equal(string(res.NextKey), fmt.Sprintf("test7denom"))
+	s.Require().Equal(uint64(10), res.Total)
+
+	s.T().Log("verify both key and offset can't be given")
+	pageReq = &query.PageRequest{Key: res.NextKey, Limit: 1, Offset: 2, CountTotal: true, Reverse: true}
+	_, _, err = execFilterPaginate(store, pageReq, appCodec)
+	s.Require().Error(err)
+
+	s.T().Log("use nextKey for query")
+	pageReq = &query.PageRequest{Key: res.NextKey, Limit: 2, CountTotal: true, Reverse: true}
+	balns, res, err = execFilterPaginate(store, pageReq, appCodec)
+	s.Require().NoError(err)
+	s.Require().NotNil(res)
+	s.Require().Equal(2, len(balns))
+	s.Require().NotNil(res.NextKey)
+	s.Require().Equal(string(res.NextKey), fmt.Sprintf("test5denom"))
+
+	s.T().Log("use nextKey for query")
+	pageReq = &query.PageRequest{Key: res.NextKey, CountTotal: true, Reverse: true}
+	balns, res, err = execFilterPaginate(store, pageReq, appCodec)
+	s.Require().NoError(err)
+	s.Require().NotNil(res)
+	fmt.Println(balns)
+	s.Require().Equal(5, len(balns))
+	s.Require().Nil(res.NextKey)
+
+	s.T().Log("verify Reverse pagination returns valid result")
+	s.Require().Equal(balns.String(), balances[2:4].Sort().String())
+
+}
+
 func ExampleFilteredPaginate() {
 	app, ctx, appCodec := setupTest()
 

types/query/pagination_test.go

@@ -188,11 +188,19 @@ func (s *paginationTestSuite) TestReversePagination() {
 	app.AccountKeeper.SetAccount(ctx, acc1)
 	s.Require().NoError(simapp.FundAccount(app, ctx, addr1, balances))
 
-	s.T().Log("verify paginate with custom limit and countTotal false")
-	pageReq := &query.PageRequest{Limit: 150}
+	s.T().Log("verify paginate with custom limit and countTotal, Reverse false")
+	pageReq := &query.PageRequest{Limit: 2, CountTotal: true, Reverse: true, Key: nil}
 	request := types.NewQueryAllBalancesRequest(addr1, pageReq)
 	res1, err := queryClient.AllBalances(gocontext.Background(), request)
 	s.Require().NoError(err)
+	s.Require().Equal(res1.Balances.Len(), 2)
+	s.Require().NotNil(res1.Pagination.NextKey)
+
+	s.T().Log("verify paginate with custom limit and countTotal, Reverse false")
+	pageReq = &query.PageRequest{Limit: 150}
+	request = types.NewQueryAllBalancesRequest(addr1, pageReq)
+	res1, err = queryClient.AllBalances(gocontext.Background(), request)
+	s.Require().NoError(err)
 	s.Require().Equal(res1.Balances.Len(), 150)
 	s.Require().NotNil(res1.Pagination.NextKey)
 	s.Require().Equal(res1.Pagination.Total, uint64(0))
@@ -233,7 +241,7 @@ func (s *paginationTestSuite) TestReversePagination() {
 	s.Require().NotNil(res.Pagination.NextKey)
 	s.Require().LessOrEqual(res.Balances.Len(), overLimit)
 
-	s.T().Log("verify paginate with custom limit, key and countTotal false")
+	s.T().Log("verify paginate with custom limit, key, countTotal false and Reverse true")
 	pageReq = &query.PageRequest{Key: res1.Pagination.NextKey, Limit: 50, Reverse: true}
 	request = types.NewQueryAllBalancesRequest(addr1, pageReq)
 	res, err = queryClient.AllBalances(gocontext.Background(), request)
@@ -242,10 +250,10 @@ func (s *paginationTestSuite) TestReversePagination() {
 	s.Require().NotNil(res.Pagination.NextKey)
 	s.Require().Equal(res.Pagination.Total, uint64(0))
 
-	s.T().Log("verify paginate returns valid result with Reverse enable & disable")
+	s.T().Log("verify Reverse pagination returns valid result")
 	s.Require().Equal(balances[100:150].String(), res.Balances.Sort().String())
 
-	s.T().Log("verify paginate with custom limit, key and countTotal false")
+	s.T().Log("verify paginate with custom limit, key, countTotal false and Reverse true")
 	pageReq = &query.PageRequest{Key: res.Pagination.NextKey, Limit: 50, Reverse: true}
 	request = types.NewQueryAllBalancesRequest(addr1, pageReq)
 	res, err = queryClient.AllBalances(gocontext.Background(), request)
@@ -254,7 +262,7 @@ func (s *paginationTestSuite) TestReversePagination() {
 	s.Require().NotNil(res.Pagination.NextKey)
 	s.Require().Equal(res.Pagination.Total, uint64(0))
 
-	s.T().Log("verify paginate returns valid result with Reverse enable & disable")
+	s.T().Log("verify Reverse pagination returns valid result")
 	s.Require().Equal(balances[50:100].String(), res.Balances.Sort().String())
 
 	s.T().Log("verify paginate with offset and key - error")