all: improve EstimateGas API

accounts/abi/abi_test.go

@@ -19,6 +19,7 @@ package abi
 import (
 	"bytes"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"log"
 	"math/big"
@@ -713,3 +714,34 @@ func TestABI_MethodById(t *testing.T) {
 	}
 
 }
+
+func TestUnpackRevert(t *testing.T) {
+	t.Parallel()
+
+	var cases = []struct {
+		input     string
+		expect    string
+		expectErr error
+	}{
+		{"", "", errors.New("invalid data for unpacking")},
+		{"08c379a1", "", errors.New("invalid data for unpacking")},
+		{"08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000d72657665727420726561736f6e00000000000000000000000000000000000000", "revert reason", nil},
+	}
+	for index, c := range cases {
+		t.Run(fmt.Sprintf("case %d", index), func(t *testing.T) {
+			got, err := UnpackRevert(common.Hex2Bytes(c.input))
+			if c.expectErr != nil {
+				if err == nil {
+					t.Fatalf("Expected non-nil error")
+				}
+				if err.Error() != c.expectErr.Error() {
+					t.Fatalf("Expected error mismatch, want %v, got %v", c.expectErr, err)
+				}
+				return
+			}
+			if c.expect != got {
+				t.Fatalf("Output mismatch, want %v, got %v", c.expect, got)
+			}
+		})
+	}
+}

accounts/abi/bind/backends/simulated.go

@@ -29,6 +29,7 @@ import (
 	"github.com/XinFinOrg/XDPoSChain/XDCx"
 	"github.com/XinFinOrg/XDPoSChain/XDCxlending"
 	"github.com/XinFinOrg/XDPoSChain/accounts"
+	"github.com/XinFinOrg/XDPoSChain/accounts/abi"
 	"github.com/XinFinOrg/XDPoSChain/accounts/abi/bind"
 	"github.com/XinFinOrg/XDPoSChain/accounts/keystore"
 	"github.com/XinFinOrg/XDPoSChain/common"
@@ -53,7 +54,6 @@ import (
 var _ bind.ContractBackend = (*SimulatedBackend)(nil)
 
 var errBlockNumberUnsupported = errors.New("SimulatedBackend cannot access blocks other than the latest block")
-var errGasEstimationFailed = errors.New("gas required exceeds allowance or always failing transaction")
 
 // SimulatedBackend implements bind.ContractBackend, simulating a blockchain in
 // the background. Its main purpose is to allow easily testing contract bindings.
@@ -276,8 +276,11 @@ func (b *SimulatedBackend) CallContract(ctx context.Context, call XDPoSChain.Cal
 	if err != nil {
 		return nil, err
 	}
-	rval, _, _, err := b.callContract(ctx, call, b.blockchain.CurrentBlock(), state)
-	return rval, err
+	res, err := b.callContract(ctx, call, b.blockchain.CurrentBlock(), state)
+	if err != nil {
+		return nil, err
+	}
+	return res.Return(), nil
 }
 
 // PendingCallContract executes a contract call on the pending state.
@@ -286,8 +289,11 @@ func (b *SimulatedBackend) PendingCallContract(ctx context.Context, call XDPoSCh
 	defer b.mu.Unlock()
 	defer b.pendingState.RevertToSnapshot(b.pendingState.Snapshot())
 
-	rval, _, _, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
-	return rval, err
+	res, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
+	if err != nil {
+		return nil, err
+	}
+	return res.Return(), nil
 }
 
 // PendingNonceAt implements PendingStateReader.PendingNonceAt, retrieving
@@ -325,39 +331,67 @@ func (b *SimulatedBackend) EstimateGas(ctx context.Context, call XDPoSChain.Call
 	cap = hi
 
 	// Create a helper to check if a gas allowance results in an executable transaction
-	executable := func(gas uint64) bool {
+	executable := func(gas uint64) (bool, *core.ExecutionResult, error) {
 		call.Gas = gas
 
 		snapshot := b.pendingState.Snapshot()
-		_, _, failed, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
+		res, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
 		b.pendingState.RevertToSnapshot(snapshot)
 
-		if err != nil || failed {
-			return false
+		if err != nil {
+			if err == core.ErrIntrinsicGas {
+				return true, nil, nil // Special case, raise gas limit
+			}
+			return true, nil, err // Bail out
 		}
-		return true
+		return res.Failed(), res, nil
 	}
 	// Execute the binary search and hone in on an executable gas limit
 	for lo+1 < hi {
 		mid := (hi + lo) / 2
-		if !executable(mid) {
+		failed, _, err := executable(mid)
+
+		// If the error is not nil(consensus error), it means the provided message
+		// call or transaction will never be accepted no matter how much gas it is
+		// assigned. Return the error directly, don't struggle any more
+		if err != nil {
+			return 0, err
+		}
+		if failed {
 			lo = mid
 		} else {
 			hi = mid
 		}
 	}
 	// Reject the transaction as invalid if it still fails at the highest allowance
 	if hi == cap {
-		if !executable(hi) {
-			return 0, errGasEstimationFailed
+		failed, result, err := executable(hi)
+		if err != nil {
+			return 0, err
+		}
+		if failed {
+			if result != nil && result.Err != vm.ErrOutOfGas {
+				errMsg := fmt.Sprintf("always failing transaction (%v)", result.Err)
+				if len(result.Revert()) > 0 {
+					ret, err := abi.UnpackRevert(result.Revert())
+					if err != nil {
+						errMsg += fmt.Sprintf(" (%#x)", result.Revert())
+					} else {
+						errMsg += fmt.Sprintf(" (%s)", ret)
+					}
+				}
+				return 0, errors.New(errMsg)
+			}
+			// Otherwise, the specified gas cap is too low
+			return 0, fmt.Errorf("gas required exceeds allowance (%d)", cap)
 		}
 	}
 	return hi, nil
 }
 
 // callContract implements common code between normal and pending contract calls.
 // state is modified during execution, make sure to copy it if necessary.
-func (b *SimulatedBackend) callContract(ctx context.Context, call XDPoSChain.CallMsg, block *types.Block, statedb *state.StateDB) (ret []byte, usedGas uint64, failed bool, err error) {
+func (b *SimulatedBackend) callContract(ctx context.Context, call XDPoSChain.CallMsg, block *types.Block, statedb *state.StateDB) (*core.ExecutionResult, error) {
 	// Ensure message is initialized properly.
 	if call.GasPrice == nil {
 		call.GasPrice = big.NewInt(1)
@@ -387,8 +421,7 @@ func (b *SimulatedBackend) callContract(ctx context.Context, call XDPoSChain.Cal
 	vmenv := vm.NewEVM(evmContext, txContext, statedb, nil, b.config, vm.Config{})
 	gaspool := new(core.GasPool).AddGas(math.MaxUint64)
 	owner := common.Address{}
-	ret, usedGas, failed, err, _ = core.NewStateTransition(vmenv, msg, gaspool).TransitionDb(owner)
-	return
+	return core.NewStateTransition(vmenv, msg, gaspool).TransitionDb(owner)
 }
 
 // SendTransaction updates the pending block to include the given transaction.

core/blockchain.go

@@ -58,7 +58,6 @@ import (
 var (
 	blockInsertTimer = metrics.NewRegisteredTimer("chain/inserts", nil)
 	CheckpointCh     = make(chan int)
-	ErrNoGenesis     = errors.New("Genesis not found in chain")
 
 	blockReorgMeter         = metrics.NewRegisteredMeter("chain/reorg/executes", nil)
 	blockReorgAddMeter      = metrics.NewRegisteredMeter("chain/reorg/add", nil)

core/error.go

@@ -26,13 +26,25 @@ var (
 	// ErrKnownBlock is returned when a block to import is already known locally.
 	ErrKnownBlock = errors.New("block already known")
 
-	// ErrGasLimitReached is returned by the gas pool if the amount of gas required
-	// by a transaction is higher than what's left in the block.
-	ErrGasLimitReached = errors.New("gas limit reached")
-
 	// ErrBlacklistedHash is returned if a block to import is on the blacklist.
 	ErrBlacklistedHash = errors.New("blacklisted hash")
 
+	// ErrNoGenesis is returned when there is no Genesis Block.
+	ErrNoGenesis = errors.New("genesis not found in chain")
+)
+
+// List of evm-call-message pre-checking errors. All state transtion messages will
+// be pre-checked before execution. If any invalidation detected, the corresponding
+// error should be returned which is defined here.
+//
+// - If the pre-checking happens in the miner, then the transaction won't be packed.
+// - If the pre-checking happens in the block processing procedure, then a "BAD BLOCk"
+// error should be emitted.
+var (
+	// ErrNonceTooLow is returned if the nonce of a transaction is lower than the
+	// one present in the local chain.
+	ErrNonceTooLow = errors.New("nonce too low")
+
 	// ErrNonceTooHigh is returned if the nonce of a transaction is higher than the
 	// next one expected based on the local chain.
 	ErrNonceTooHigh = errors.New("nonce too high")
@@ -41,6 +53,22 @@ var (
 	// maximum allowed value and would become invalid if incremented.
 	ErrNonceMax = errors.New("nonce has max value")
 
+	// ErrGasLimitReached is returned by the gas pool if the amount of gas required
+	// by a transaction is higher than what's left in the block.
+	ErrGasLimitReached = errors.New("gas limit reached")
+
+	// ErrInsufficientFundsForTransfer is returned if the transaction sender doesn't
+	// have enough funds for transfer(topmost call only).
+	ErrInsufficientFundsForTransfer = errors.New("insufficient funds for transfer")
+
+	// ErrInsufficientFunds is returned if the total cost of executing a transaction
+	// is higher than the balance of the user's account.
+	ErrInsufficientFunds = errors.New("insufficient funds for gas * price + value")
+
+	// ErrIntrinsicGas is returned if the transaction is specified to use less gas
+	// than required to start the invocation.
+	ErrIntrinsicGas = errors.New("intrinsic gas too low")
+
 	ErrNotXDPoS = errors.New("XDPoS not found in config")
 
 	ErrNotFoundM1 = errors.New("list M1 not found ")

core/state_processor.go

@@ -406,7 +406,7 @@ func applyTransaction(config *params.ChainConfig, tokensFee map[common.Address]*
 	// End Bypass blacklist address
 
 	// Apply the transaction to the current state (included in the env)
-	_, gas, failed, err, _ := ApplyMessage(evm, msg, gp, coinbaseOwner)
+	result, err := ApplyMessage(evm, msg, gp, coinbaseOwner)
 
 	if err != nil {
 		return nil, 0, err, false
@@ -419,18 +419,18 @@ func applyTransaction(config *params.ChainConfig, tokensFee map[common.Address]*
 	} else {
 		root = statedb.IntermediateRoot(config.IsEIP158(header.Number)).Bytes()
 	}
-	*usedGas += gas
+	*usedGas += result.UsedGas
 
 	// Create a new receipt for the transaction, storing the intermediate root and gas used
 	// by the tx.
 	receipt := &types.Receipt{Type: tx.Type(), PostState: root, CumulativeGasUsed: *usedGas}
-	if failed {
+	if result.Failed() {
 		receipt.Status = types.ReceiptStatusFailed
 	} else {
 		receipt.Status = types.ReceiptStatusSuccessful
 	}
 	receipt.TxHash = tx.Hash()
-	receipt.GasUsed = gas
+	receipt.GasUsed = result.UsedGas
 
 	// If the transaction created a contract, store the creation address in the receipt.
 	if msg.To() == nil {
@@ -443,10 +443,10 @@ func applyTransaction(config *params.ChainConfig, tokensFee map[common.Address]*
 	receipt.BlockHash = statedb.BlockHash()
 	receipt.BlockNumber = header.Number
 	receipt.TransactionIndex = uint(statedb.TxIndex())
-	if balanceFee != nil && failed {
+	if balanceFee != nil && result.Failed() {
 		state.PayFeeWithTRC21TxFail(statedb, msg.From(), *to)
 	}
-	return receipt, gas, err, balanceFee != nil
+	return receipt, result.UsedGas, err, balanceFee != nil
 }
 
 // ApplyTransaction attempts to apply a transaction to the given state database
@@ -457,7 +457,7 @@ func ApplyTransaction(config *params.ChainConfig, tokensFee map[common.Address]*
 	// Create a new context to be used in the EVM environment
 	blockContext := NewEVMBlockContext(header, bc, author)
 	vmenv := vm.NewEVM(blockContext, vm.TxContext{}, statedb, XDCxState, config, cfg)
-	return applyTransaction(config, tokensFee, bc, author, gp, statedb, XDCxState, header, tx , usedGas, vmenv)
+	return applyTransaction(config, tokensFee, bc, author, gp, statedb, XDCxState, header, tx, usedGas, vmenv)
 }
 
 func ApplySignTransaction(config *params.ChainConfig, statedb *state.StateDB, header *types.Header, tx *types.Transaction, usedGas *uint64) (*types.Receipt, uint64, error, bool) {