fix: Staking delegations should return empty list instead of rpc error when no records found

x/staking/client/rest/grpc_query_test.go

@@ -414,39 +414,15 @@ func (s *IntegrationTestSuite) TestQueryUnbondingDelegationGRPC() {
 	}
 }
 
-func (s *IntegrationTestSuite) TestQueryDelegationsResponseCode() {
+func (s *IntegrationTestSuite) TestQueryDelegatorDelegationsGRPC() {
 	val := s.network.Validators[0]
+	baseURL := val.APIAddress
 
-	// Create new account in the keyring.
+	// Create new account in the keyring for address without delegations.
 	info, _, err := val.ClientCtx.Keyring.NewMnemonic("test", keyring.English, sdk.FullFundraiserPath, keyring.DefaultBIP39Passphrase, hd.Secp256k1)
 	s.Require().NoError(err)
 	newAddr := sdk.AccAddress(info.GetPubKey().Address())
 
-	s.T().Log("expect 404 error for address without delegations")
-	res, statusCode, err := getRequest(fmt.Sprintf("%s/cosmos/staking/v1beta1/delegations/%s", val.APIAddress, newAddr.String()))
-	s.Require().NoError(err)
-	s.Require().Contains(string(res), "\"code\": 5")
-	s.Require().Equal(404, statusCode)
-}
-
-func getRequest(url string) ([]byte, int, error) {
-	res, err := http.Get(url) // nolint:gosec
-	body, err := ioutil.ReadAll(res.Body)
-	if err != nil {
-		return nil, res.StatusCode, err
-	}
-
-	if err = res.Body.Close(); err != nil {
-		return nil, res.StatusCode, err
-	}
-
-	return body, res.StatusCode, nil
-}
-
-func (s *IntegrationTestSuite) TestQueryDelegatorDelegationsGRPC() {
-	val := s.network.Validators[0]
-	baseURL := val.APIAddress
-
 	testCases := []struct {
 		name         string
 		url          string
@@ -486,6 +462,19 @@ func (s *IntegrationTestSuite) TestQueryDelegatorDelegationsGRPC() {
 				Pagination: &query.PageResponse{Total: 1},
 			},
 		},
+		{
+			"address without delegations",
+			fmt.Sprintf("%s/cosmos/staking/v1beta1/delegations/%s", baseURL, newAddr.String()),
+			map[string]string{
+				grpctypes.GRPCBlockHeightHeader: "1",
+			},
+			false,
+			&types.QueryDelegatorDelegationsResponse{},
+			&types.QueryDelegatorDelegationsResponse{
+				DelegationResponses: types.DelegationResponses{},
+				Pagination:          &query.PageResponse{Total: 0},
+			},
+		},
 	}
 
 	for _, tc := range testCases {
@@ -506,6 +495,20 @@ func (s *IntegrationTestSuite) TestQueryDelegatorDelegationsGRPC() {
 	}
 }
 
+func getRequest(url string) ([]byte, int, error) {
+	res, err := http.Get(url) // nolint:gosec
+	body, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, res.StatusCode, err
+	}
+
+	if err = res.Body.Close(); err != nil {
+		return nil, res.StatusCode, err
+	}
+
+	return body, res.StatusCode, nil
+}
+
 func (s *IntegrationTestSuite) TestQueryDelegatorUnbondingDelegationsGRPC() {
 	val := s.network.Validators[0]
 	baseURL := val.APIAddress

x/staking/keeper/grpc_query.go

@@ -281,11 +281,6 @@ func (k Querier) DelegatorDelegations(c context.Context, req *types.QueryDelegat
 		return nil, status.Error(codes.Internal, err.Error())
 	}
 
-	if delegations == nil {
-		return nil, status.Errorf(
-			codes.NotFound,
-			"unable to find delegations for address %s", req.DelegatorAddr)
-	}
 	delegationResps, err := DelegationsToDelegationResponses(ctx, k.Keeper, delegations)
 	if err != nil {
 		return nil, status.Error(codes.Internal, err.Error())

x/staking/keeper/grpc_query_test.go

@@ -288,36 +288,45 @@ func (suite *KeeperTestSuite) TestGRPCQueryDelegatorDelegations() {
 		msg      string
 		malleate func()
 		expPass  bool
+		expErr   bool
 	}{
 		{"empty request",
 			func() {
 				req = &types.QueryDelegatorDelegationsRequest{}
 			},
 			false,
+			true,
 		}, {"invalid request",
 			func() {
 				req = &types.QueryDelegatorDelegationsRequest{DelegatorAddr: addrs[4].String()}
 			},
 			false,
+			false,
 		},
 		{"valid request",
 			func() {
 				req = &types.QueryDelegatorDelegationsRequest{DelegatorAddr: addrAcc.String(),
 					Pagination: &query.PageRequest{Limit: 1, CountTotal: true}}
 			},
 			true,
+			false,
 		},
 	}
 
 	for _, tc := range testCases {
 		suite.Run(fmt.Sprintf("Case %s", tc.msg), func() {
 			tc.malleate()
 			res, err := queryClient.DelegatorDelegations(gocontext.Background(), req)
-			if tc.expPass {
+			if tc.expPass && !tc.expErr {
+				suite.NoError(err)
+				suite.NotNil(res.Pagination.NextKey)
 				suite.Equal(uint64(2), res.Pagination.Total)
 				suite.Len(res.DelegationResponses, 1)
 				suite.Equal(1, len(res.DelegationResponses))
 				suite.Equal(sdk.NewCoin(sdk.DefaultBondDenom, delegation.Shares.TruncateInt()), res.DelegationResponses[0].Balance)
+			} else if !tc.expPass && !tc.expErr {
+				suite.NoError(err)
+				suite.Nil(res.DelegationResponses)
 			} else {
 				suite.Error(err)
 				suite.Nil(res)