fix(rpc): different result from eth_getProof comparing with Ethereum (#1431)

* align with eth_getProof

for more info, see https://eips.ethereum.org/EIPS/eip-1186

* add GetHexProofs

* add change doc

* keep default res

* fix lint

* add e2e test

* Apply suggestions from code review

* fix lint

* nix run -f ./nix gomod2nix

rpc/backend/account_info.go

@@ -75,16 +75,10 @@ func (b *Backend) GetProof(address common.Address, storageKeys []string, blockNr
 			return nil, err
 		}
 
-		// check for proof
-		var proofStr string
-		if proof != nil {
-			proofStr = proof.String()
-		}
-
 		storageProofs[i] = rpctypes.StorageResult{
 			Key:   key,
 			Value: (*hexutil.Big)(new(big.Int).SetBytes(valueBz)),
-			Proof: []string{proofStr},
+			Proof: GetHexProofs(proof),
 		}
 	}
 
@@ -105,12 +99,6 @@ func (b *Backend) GetProof(address common.Address, storageKeys []string, blockNr
 		return nil, err
 	}
 
-	// check for proof
-	var accProofStr string
-	if proof != nil {
-		accProofStr = proof.String()
-	}
-
 	balance, ok := sdkmath.NewIntFromString(res.Balance)
 	if !ok {
 		return nil, errors.New("invalid balance")
@@ -118,7 +106,7 @@ func (b *Backend) GetProof(address common.Address, storageKeys []string, blockNr
 
 	return &rpctypes.AccountResult{
 		Address:      address,
-		AccountProof: []string{accProofStr},
+		AccountProof: GetHexProofs(proof),
 		Balance:      (*hexutil.Big)(balance.BigInt()),
 		CodeHash:     common.HexToHash(res.CodeHash),
 		Nonce:        hexutil.Uint64(res.Nonce),

rpc/backend/utils.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/evmos/ethermint/rpc/types"
 	evmtypes "github.com/evmos/ethermint/x/evm/types"
+	"github.com/tendermint/tendermint/proto/tendermint/crypto"
 )
 
 type txGasAndReward struct {
@@ -263,3 +264,20 @@ func GetLogsFromBlockResults(blockRes *tmrpctypes.ResultBlockResults) ([][]*etht
 
 	return blockLogs, nil
 }
+
+// GetHexProofs returns list of hex data of proof op
+func GetHexProofs(proof *crypto.ProofOps) []string {
+	if proof == nil {
+		return []string{""}
+	}
+	proofs := []string{}
+	// check for proof
+	for _, p := range proof.Ops {
+		proof := ""
+		if len(p.Data) > 0 {
+			proof = hexutil.Encode(p.Data)
+		}
+		proofs = append(proofs, proof)
+	}
+	return proofs
+}

rpc/backend/utils_test.go

@@ -0,0 +1,52 @@
+package backend
+
+import (
+	"fmt"
+
+	"github.com/tendermint/tendermint/proto/tendermint/crypto"
+)
+
+func mookProofs(num int, withData bool) *crypto.ProofOps {
+	var proofOps *crypto.ProofOps
+	if num > 0 {
+		proofOps = new(crypto.ProofOps)
+		for i := 0; i < num; i++ {
+			proof := crypto.ProofOp{}
+			if withData {
+				proof.Data = []byte("\n\031\n\003KEY\022\005VALUE\032\013\010\001\030\001 \001*\003\000\002\002")
+			}
+			proofOps.Ops = append(proofOps.Ops, proof)
+		}
+	}
+	return proofOps
+}
+
+func (suite *BackendTestSuite) TestGetHexProofs() {
+	defaultRes := []string{""}
+	testCases := []struct {
+		name  string
+		proof *crypto.ProofOps
+		exp   []string
+	}{
+		{
+			"no proof provided",
+			mookProofs(0, false),
+			defaultRes,
+		},
+		{
+			"no proof data provided",
+			mookProofs(1, false),
+			defaultRes,
+		},
+		{
+			"valid proof provided",
+			mookProofs(1, true),
+			[]string{"0x0a190a034b4559120556414c55451a0b0801180120012a03000202"},
+		},
+	}
+	for _, tc := range testCases {
+		suite.Run(fmt.Sprintf("Case %s", tc.name), func() {
+			suite.Require().Equal(tc.exp, GetHexProofs(tc.proof))
+		})
+	}
+}