address PR comments

Author: ganeshvanahalli

eth/gasestimator/gasestimator.go

@@ -42,11 +42,12 @@ const EstimateGasErrorRatio = 0.015
 // these together, it would be excessively hard to test. Splitting the parts out
 // allows testing without needing a proper live chain.
 type Options struct {
-	Config  *params.ChainConfig // Chain configuration for hard fork selection
-	Chain   core.ChainContext   // Chain context to access past block hashes
-	Header  *types.Header       // Header defining the block context to execute in
-	State   *state.StateDB      // Pre-state on top of which to estimate the gas
-	Backend core.NodeInterfaceBackendAPI
+	Config           *params.ChainConfig // Chain configuration for hard fork selection
+	Chain            core.ChainContext   // Chain context to access past block hashes
+	Header           *types.Header       // Header defining the block context to execute in
+	State            *state.StateDB      // Pre-state on top of which to estimate the gas
+	Backend          core.NodeInterfaceBackendAPI
+	RunScheduledTxes func(context.Context, core.NodeInterfaceBackendAPI, *state.StateDB, *types.Header, vm.BlockContext, core.MessageRunMode, *core.ExecutionResult) (*core.ExecutionResult, error)
 
 	ErrorRatio float64 // Allowed overestimation ratio for faster estimation termination
 }
@@ -235,8 +236,7 @@ func run(ctx context.Context, call *core.Message, opts *Options) (*core.Executio
 		evm.Cancel()
 	}()
 	// Execute the call, returning a wrapped error or the result
-	gp := new(core.GasPool).AddGas(math.MaxUint64)
-	result, err := core.ApplyMessage(evm, call, gp)
+	result, err := core.ApplyMessage(evm, call, new(core.GasPool).AddGas(math.MaxUint64))
 	if vmerr := dirtyState.Error(); vmerr != nil {
 		return nil, vmerr
 	}
@@ -245,42 +245,9 @@ func run(ctx context.Context, call *core.Message, opts *Options) (*core.Executio
 	}
 
 	// Arbitrum: a tx can schedule another (see retryables)
-	scheduled := result.ScheduledTxes
-	for len(scheduled) > 0 {
-		// This will panic if the scheduled tx is signed, but we only schedule unsigned ones
-		msg, err := core.TransactionToMessage(scheduled[0], types.NewArbitrumSigner(nil), opts.Header.BaseFee)
-		if err != nil {
-			return nil, err
-		}
-		// The scheduling transaction will "use" all of the gas available to it,
-		// but it's really just passing it on to the scheduled tx, so we subtract it out here.
-		if result.UsedGas >= msg.GasLimit {
-			result.UsedGas -= msg.GasLimit
-		} else {
-			log.Warn("Scheduling tx used less gas than scheduled tx has available", "usedGas", result.UsedGas, "scheduledGas", msg.GasLimit)
-			result.UsedGas = 0
-		}
-		msg.TxRunMode = core.MessageGasEstimationMode
-		// make a new EVM for the scheduled Tx (an EVM must never be reused)
-		evm := opts.Backend.GetEVM(ctx, msg, dirtyState, opts.Header, &vm.Config{NoBaseFee: true}, &evmContext)
-		go func() {
-			<-ctx.Done()
-			evm.Cancel()
-		}()
-
-		scheduledTxResult, err := core.ApplyMessage(evm, msg, gp)
-		if err != nil {
-			return nil, err // Bail out
-		}
-		if err := dirtyState.Error(); err != nil {
-			return nil, err
-		}
-		if scheduledTxResult.Failed() {
-			return scheduledTxResult, nil
-		}
-		// Add back in any gas used by the scheduled transaction.
-		result.UsedGas += scheduledTxResult.UsedGas
-		scheduled = append(scheduled[1:], scheduledTxResult.ScheduledTxes...)
+	result, err = opts.RunScheduledTxes(ctx, opts.Backend, dirtyState, opts.Header, evmContext, core.MessageGasEstimationMode, result)
+	if err != nil {
+		return nil, err
 	}
 
 	return result, nil

internal/ethapi/api.go

@@ -1129,6 +1129,15 @@ func doCall(ctx context.Context, b Backend, args TransactionArgs, state *state.S
 	}
 
 	// Arbitrum: a tx can schedule another (see retryables)
+	result, err = runScheduledTxes(ctx, b, state, header, blockCtx, core.MessageGasEstimationMode, result)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}
+
+func runScheduledTxes(ctx context.Context, b core.NodeInterfaceBackendAPI, state *state.StateDB, header *types.Header, blockCtx vm.BlockContext, runMode core.MessageRunMode, result *core.ExecutionResult) (*core.ExecutionResult, error) {
 	scheduled := result.ScheduledTxes
 	for runMode == core.MessageGasEstimationMode && len(scheduled) > 0 {
 		// This will panic if the scheduled tx is signed, but we only schedule unsigned ones
@@ -1152,7 +1161,7 @@ func doCall(ctx context.Context, b Backend, args TransactionArgs, state *state.S
 			evm.Cancel()
 		}()
 
-		scheduledTxResult, err := core.ApplyMessage(evm, msg, gp)
+		scheduledTxResult, err := core.ApplyMessage(evm, msg, new(core.GasPool).AddGas(math.MaxUint64))
 		if err != nil {
 			return nil, err // Bail out
 		}
@@ -1166,7 +1175,6 @@ func doCall(ctx context.Context, b Backend, args TransactionArgs, state *state.S
 		result.UsedGas += scheduledTxResult.UsedGas
 		scheduled = append(scheduled[1:], scheduledTxResult.ScheduledTxes...)
 	}
-
 	return result, nil
 }
 
@@ -1280,12 +1288,13 @@ func DoEstimateGas(ctx context.Context, b Backend, args TransactionArgs, blockNr
 
 	// Construct the gas estimator option from the user input
 	opts := &gasestimator.Options{
-		Config:     b.ChainConfig(),
-		Chain:      NewChainContext(ctx, b),
-		Header:     header,
-		State:      state,
-		Backend:    b,
-		ErrorRatio: gasestimator.EstimateGasErrorRatio,
+		Config:           b.ChainConfig(),
+		Chain:            NewChainContext(ctx, b),
+		Header:           header,
+		State:            state,
+		Backend:          b,
+		ErrorRatio:       gasestimator.EstimateGasErrorRatio,
+		RunScheduledTxes: runScheduledTxes,
 	}
 	// Run the gas estimation andwrap any revertals into a custom return
 	// Arbitrum: this also appropriately recursively calls another args.ToMessage with increased gasCap by posterCostInL2Gas amount