feat(evm): query fungible token mappings by cosmos denom or ERC20 address

CHANGELOG.md

@@ -78,6 +78,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - [#1922](https://github.com/NibiruChain/nibiru/pull/1922) - feat(evm): tracer option is read from the config.
 - [#1936](https://github.com/NibiruChain/nibiru/pull/1936) - feat(evm): EVM fungible token protobufs and encoding tests
 - [#1947](https://github.com/NibiruChain/nibiru/pull/1947) - fix(evm): fix FunToken state marshalling
+- [#1949](https://github.com/NibiruChain/nibiru/pull/1949) - feat(evm): add fungible token mapping queries
 
 #### Dapp modules: perp, spot, oracle, etc
 

proto/eth/evm/v1/query.proto

@@ -75,6 +75,10 @@ service Query {
   rpc BaseFee(QueryBaseFeeRequest) returns (QueryBaseFeeResponse) {
     option (google.api.http).get = "/nibiru/evm/v1/base_fee";
   }
+
+  rpc TokenMapping(QueryTokenMappingRequest) returns (QueryTokenMappingResponse) {
+    option (google.api.http).get = "/nibiru/evm/v1/token_mapping/{token}";
+  }
 }
 
 // QueryEthAccountRequest is the request type for the Query/Account RPC method.
@@ -301,3 +305,19 @@ message QueryBaseFeeResponse {
   // base_fee is the EIP1559 base fee
   string base_fee = 1 [(gogoproto.customtype) = "cosmossdk.io/math.Int"];
 }
+
+message QueryTokenMappingRequest {
+  option (gogoproto.equal) = false;
+  option (gogoproto.goproto_getters) = false;
+
+  // either the 0x contract address of the ERC-20 token or the cosmos denom
+  string token = 1;
+}
+
+message QueryTokenMappingResponse {
+  option (gogoproto.equal) = false;
+  option (gogoproto.goproto_getters) = false;  
+
+  // fun_token is a mapping between the Cosmos native coin and the ERC20 contract address
+  FunToken fun_token = 1;
+}

x/evm/keeper/grpc_query.go

@@ -740,3 +740,30 @@ func (k *Keeper) TraceEthTxMsg(
 
 	return &result, txConfig.LogIndex + uint(len(res.Logs)), nil
 }
+
+func (k Keeper) TokenMapping(
+	goCtx context.Context, req *evm.QueryTokenMappingRequest,
+) (*evm.QueryTokenMappingResponse, error) {
+	ctx := sdk.UnwrapSDKContext(goCtx)
+
+	// first try lookup by cosmos denom
+	bankDenomIter := k.FunTokens.Indexes.BankDenom.ExactMatch(ctx, req.Token)
+	funTokenMappings := k.FunTokens.Collect(ctx, bankDenomIter)
+	if len(funTokenMappings) > 0 {
+		// assumes that there is only one mapping for a given denom
+		return &evm.QueryTokenMappingResponse{
+			FunToken: &funTokenMappings[0],
+		}, nil
+	}
+
+	erc20AddrIter := k.FunTokens.Indexes.ERC20Addr.ExactMatch(ctx, gethcommon.HexToAddress(req.Token))
+	funTokenMappings = k.FunTokens.Collect(ctx, erc20AddrIter)
+	if len(funTokenMappings) > 0 {
+		// assumes that there is only one mapping for a given erc20 address
+		return &evm.QueryTokenMappingResponse{
+			FunToken: &funTokenMappings[0],
+		}, nil
+	}
+
+	return nil, grpcstatus.Errorf(grpccodes.NotFound, "token mapping not found for %s", req.Token)
+}

x/evm/keeper/grpc_query_test.go

@@ -894,3 +894,91 @@
 		})
 	}
 }
+
+func (s *KeeperSuite) TestQueryTokenMapping() {
+	type In = *evm.QueryTokenMappingRequest
+	type Out = *evm.QueryTokenMappingResponse
+	testCases := []TestCase[In, Out]{
+		{
+			name: "sad: no token mapping",
+			scenario: func(deps *evmtest.TestDeps) (req In, wantResp Out) {
+				req = &evm.QueryTokenMappingRequest{
+					Token: "unibi",
+				}
+				wantResp = &evm.QueryTokenMappingResponse{
+					FunToken: nil,
+				}
+				return req, wantResp
+			},
+			wantErr: "token mapping not found for unibi",
+		},
+		{
+			name: "happy: token mapping exists from cosmos coin -> ERC20 token",
+			setup: func(deps *evmtest.TestDeps) {
+				deps.K.FunTokens.SafeInsert(
+					deps.Ctx,
+					gethcommon.HexToAddress("0xAEf9437FF23D48D73271a41a8A094DEc9ac71477"),
+					"unibi",
+					true,
+				)
+			},
+			scenario: func(deps *evmtest.TestDeps) (req In, wantResp Out) {
+				req = &evm.QueryTokenMappingRequest{
+					Token: "unibi",
+				}
+				wantResp = &evm.QueryTokenMappingResponse{
+					FunToken: &evm.FunToken{
+						Erc20Addr:      "0xAEf9437FF23D48D73271a41a8A094DEc9ac71477",
+						BankDenom:      "unibi",
+						IsMadeFromCoin: true,
+					},
+				}
+				return req, wantResp
+			},
+			wantErr: "",
+		},
+		{
+			name: "happy: token mapping exists from ERC20 token -> cosmos coin",
+			setup: func(deps *evmtest.TestDeps) {
+				deps.K.FunTokens.SafeInsert(
+					deps.Ctx,
+					gethcommon.HexToAddress("0xAEf9437FF23D48D73271a41a8A094DEc9ac71477"),
+					"unibi",
+					true,
+				)
+			},
+			scenario: func(deps *evmtest.TestDeps) (req In, wantResp Out) {
+				req = &evm.QueryTokenMappingRequest{
+					Token: "0xAEf9437FF23D48D73271a41a8A094DEc9ac71477",
+				}
+				wantResp = &evm.QueryTokenMappingResponse{
+					FunToken: &evm.FunToken{
+						Erc20Addr:      "0xAEf9437FF23D48D73271a41a8A094DEc9ac71477",
+						BankDenom:      "unibi",
+						IsMadeFromCoin: true,
+					},
+				}
+				return req, wantResp
+			},
+			wantErr: "",
+		},
+	}
+
+	for _, tc := range testCases {
+		s.Run(tc.name, func() {
+			deps := evmtest.NewTestDeps()
+			if tc.setup != nil {
+				tc.setup(&deps)
+			}
+			req, wantResp := tc.scenario(&deps)
+			goCtx := sdk.WrapSDKContext(deps.Ctx)
+			gotResp, err := deps.K.TokenMapping(goCtx, req)
+			if tc.wantErr != "" {
+				s.Require().ErrorContains(err, tc.wantErr)
+				return
+			}
+			s.Assert().NoError(err)
+			s.EqualValues(wantResp, gotResp)
+		})
+	}
+}