Merge PR #6618: backport 0.39.0 (launchpad): cherry pick #5839

CHANGELOG.md

@@ -60,6 +60,10 @@ pruning setting `syncable` used `KeepEvery:100`.
   0.38.5, as doing so may cause data loss and data corruption.
 * Otherwise, consider syncing the node from scratch with 0.38.5.
 
+### API Breaking Changes
+
+* (baseapp) [\#5837](https://github.com/cosmos/cosmos-sdk/issues/5837) Transaction simulation now returns a `SimulationResponse` which contains the `GasInfo` and `Result` from the execution.
+
 ### Improvements
 
 * (deps) Bump Tendermint version to [v0.33.5](https://github.com/tendermint/tendermint/releases/tag/v0.33.5)

baseapp/abci.go

@@ -326,12 +326,20 @@ func handleQueryApp(app *BaseApp, path []string, req abci.RequestQuery) abci.Res
 				return sdkerrors.QueryResult(sdkerrors.Wrap(err, "failed to decode tx"))
 			}
 
-			gInfo, _, _ := app.Simulate(txBytes, tx)
+			gInfo, res, err := app.Simulate(txBytes, tx)
+			if err != nil {
+				return sdkerrors.QueryResult(sdkerrors.Wrap(err, "failed to simulate tx"))
+			}
+
+			simRes := sdk.SimulationResponse{
+				GasInfo: gInfo,
+				Result:  res,
+			}
 
 			return abci.ResponseQuery{
 				Codespace: sdkerrors.RootCodespace,
 				Height:    req.Height,
-				Value:     codec.Cdc.MustMarshalBinaryLengthPrefixed(gInfo.GasUsed),
+				Value:     codec.Cdc.MustMarshalBinaryBare(simRes),
 			}
 
 		case "version":

baseapp/baseapp_test.go

@@ -958,10 +958,13 @@ func TestSimulateTx(t *testing.T) {
 		queryResult := app.Query(query)
 		require.True(t, queryResult.IsOK(), queryResult.Log)
 
-		var res uint64
-		err = codec.Cdc.UnmarshalBinaryLengthPrefixed(queryResult.Value, &res)
+		var simRes sdk.SimulationResponse
+		err = codec.Cdc.UnmarshalBinaryBare(queryResult.Value, &simRes)
 		require.NoError(t, err)
-		require.Equal(t, gasConsumed, res)
+		require.Equal(t, gInfo, simRes.GasInfo)
+		require.Equal(t, result.Log, simRes.Result.Log)
+		require.Equal(t, result.Events, simRes.Result.Events)
+		require.True(t, bytes.Equal(result.Data, simRes.Result.Data))
 		app.EndBlock(abci.RequestEndBlock{})
 		app.Commit()
 	}

types/result.go

@@ -17,7 +17,7 @@ type GasInfo struct {
 	// GasWanted is the maximum units of work we allow this tx to perform.
 	GasWanted uint64
 
-	// GasUsed is the amount of gas actually consumed. NOTE: unimplemented
+	// GasUsed is the amount of gas actually consumed.
 	GasUsed uint64
 }
 
@@ -35,6 +35,13 @@ type Result struct {
 	Events Events
 }
 
+// SimulationResponse defines the response generated when a transaction is successfully
+// simulated by the Baseapp.
+type SimulationResponse struct {
+	GasInfo
+	Result *Result
+}
+
 // ABCIMessageLogs represents a slice of ABCIMessageLog.
 type ABCIMessageLogs []ABCIMessageLog
 

x/auth/client/utils/tx.go

@@ -120,26 +120,26 @@ func EnrichWithGas(txBldr authtypes.TxBuilder, cliCtx context.CLIContext, msgs [
 }
 
 // CalculateGas simulates the execution of a transaction and returns
-// both the estimate obtained by the query and the adjusted amount.
+// the simulation response obtained by the query and the adjusted gas amount.
 func CalculateGas(
 	queryFunc func(string, []byte) ([]byte, int64, error), cdc *codec.Codec,
 	txBytes []byte, adjustment float64,
-) (estimate, adjusted uint64, err error) {
+) (sdk.SimulationResponse, uint64, error) {
 
 	// run a simulation (via /app/simulate query) to
 	// estimate gas and update TxBuilder accordingly
 	rawRes, _, err := queryFunc("/app/simulate", txBytes)
 	if err != nil {
-		return estimate, adjusted, err
+		return sdk.SimulationResponse{}, 0, err
 	}
 
-	estimate, err = parseQueryResponse(cdc, rawRes)
+	simRes, err := parseQueryResponse(cdc, rawRes)
 	if err != nil {
-		return
+		return sdk.SimulationResponse{}, 0, err
 	}
 
-	adjusted = adjustGasEstimate(estimate, adjustment)
-	return estimate, adjusted, nil
+	adjusted := adjustGasEstimate(simRes.GasUsed, adjustment)
+	return simRes, adjusted, nil
 }
 
 // PrintUnsignedStdTx builds an unsigned StdTx and prints it to os.Stdout.
@@ -261,29 +261,28 @@ func GetTxEncoder(cdc *codec.Codec) (encoder sdk.TxEncoder) {
 	return encoder
 }
 
-// nolint
-// SimulateMsgs simulates the transaction and returns the gas estimate and the adjusted value.
-func simulateMsgs(txBldr authtypes.TxBuilder, cliCtx context.CLIContext, msgs []sdk.Msg) (estimated, adjusted uint64, err error) {
+// simulateMsgs simulates the transaction and returns the simulation response and
+// the adjusted gas value.
+func simulateMsgs(txBldr authtypes.TxBuilder, cliCtx context.CLIContext, msgs []sdk.Msg) (sdk.SimulationResponse, uint64, error) {
 	txBytes, err := txBldr.BuildTxForSim(msgs)
 	if err != nil {
-		return
+		return sdk.SimulationResponse{}, 0, err
 	}
 
-	estimated, adjusted, err = CalculateGas(cliCtx.QueryWithData, cliCtx.Codec, txBytes, txBldr.GasAdjustment())
-	return
+	return CalculateGas(cliCtx.QueryWithData, cliCtx.Codec, txBytes, txBldr.GasAdjustment())
 }
 
 func adjustGasEstimate(estimate uint64, adjustment float64) uint64 {
 	return uint64(adjustment * float64(estimate))
 }
 
-func parseQueryResponse(cdc *codec.Codec, rawRes []byte) (uint64, error) {
-	var gasUsed uint64
-	if err := cdc.UnmarshalBinaryLengthPrefixed(rawRes, &gasUsed); err != nil {
-		return 0, err
+func parseQueryResponse(cdc *codec.Codec, rawRes []byte) (sdk.SimulationResponse, error) {
+	var simRes sdk.SimulationResponse
+	if err := cdc.UnmarshalBinaryBare(rawRes, &simRes); err != nil {
+		return sdk.SimulationResponse{}, err
 	}
 
-	return gasUsed, nil
+	return simRes, nil
 }
 
 // PrepareTxBuilder populates a TxBuilder in preparation for the build of a Tx.

x/auth/client/utils/tx_test.go

@@ -7,8 +7,8 @@ import (
 	"os"
 	"testing"
 
-	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
 	"github.com/tendermint/tendermint/crypto/ed25519"
 
 	"github.com/cosmos/cosmos-sdk/codec"
@@ -23,23 +23,34 @@ var (
 
 func TestParseQueryResponse(t *testing.T) {
 	cdc := makeCodec()
-	sdkResBytes := cdc.MustMarshalBinaryLengthPrefixed(uint64(10))
-	gas, err := parseQueryResponse(cdc, sdkResBytes)
-	assert.Equal(t, gas, uint64(10))
-	assert.Nil(t, err)
-	gas, err = parseQueryResponse(cdc, []byte("fuzzy"))
-	assert.Equal(t, gas, uint64(0))
-	assert.Error(t, err)
+	simRes := sdk.SimulationResponse{
+		GasInfo: sdk.GasInfo{GasUsed: 10, GasWanted: 20},
+		Result:  &sdk.Result{Data: []byte("tx data"), Log: "log"},
+	}
+
+	bz := cdc.MustMarshalBinaryBare(simRes)
+	res, err := parseQueryResponse(cdc, bz)
+	require.NoError(t, err)
+	require.Equal(t, 10, int(res.GasInfo.GasUsed))
+	require.NotNil(t, res.Result)
+
+	res, err = parseQueryResponse(cdc, []byte("fuzzy"))
+	require.Error(t, err)
 }
 
 func TestCalculateGas(t *testing.T) {
 	cdc := makeCodec()
 	makeQueryFunc := func(gasUsed uint64, wantErr bool) func(string, []byte) ([]byte, int64, error) {
 		return func(string, []byte) ([]byte, int64, error) {
 			if wantErr {
-				return nil, 0, errors.New("")
+				return nil, 0, errors.New("query failed")
+			}
+			simRes := sdk.SimulationResponse{
+				GasInfo: sdk.GasInfo{GasUsed: gasUsed, GasWanted: gasUsed},
+				Result:  &sdk.Result{Data: []byte("tx data"), Log: "log"},
 			}
-			return cdc.MustMarshalBinaryLengthPrefixed(gasUsed), 0, nil
+
+			return cdc.MustMarshalBinaryBare(simRes), 0, nil
 		}
 	}
 
@@ -54,20 +65,26 @@ func TestCalculateGas(t *testing.T) {
 		args         args
 		wantEstimate uint64
 		wantAdjusted uint64
-		wantErr      bool
+		expPass      bool
 	}{
-		{"error", args{0, true, 1.2}, 0, 0, true},
-		{"adjusted gas", args{10, false, 1.2}, 10, 12, false},
+		{"error", args{0, true, 1.2}, 0, 0, false},
+		{"adjusted gas", args{10, false, 1.2}, 10, 12, true},
 	}
 
 	for _, tt := range tests {
 		tt := tt
 		t.Run(tt.name, func(t *testing.T) {
 			queryFunc := makeQueryFunc(tt.args.queryFuncGasUsed, tt.args.queryFuncWantErr)
-			gotEstimate, gotAdjusted, err := CalculateGas(queryFunc, cdc, []byte(""), tt.args.adjustment)
-			assert.Equal(t, err != nil, tt.wantErr)
-			assert.Equal(t, gotEstimate, tt.wantEstimate)
-			assert.Equal(t, gotAdjusted, tt.wantAdjusted)
+			simRes, gotAdjusted, err := CalculateGas(queryFunc, cdc, []byte(""), tt.args.adjustment)
+			if tt.expPass {
+				require.NoError(t, err)
+				require.Equal(t, simRes.GasInfo.GasUsed, tt.wantEstimate)
+				require.Equal(t, gotAdjusted, tt.wantAdjusted)
+				require.NotNil(t, simRes.Result)
+			} else {
+				require.Error(t, err)
+				require.Nil(t, simRes.Result)
+			}
 		})
 	}
 }