all: improve EstimateGas API (ethereum#20830)

Author: JukLee0ira

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"
@@ -54,7 +55,6 @@ 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.
@@ -161,6 +161,12 @@ func NewSimulatedBackend(alloc core.GenesisAlloc) *SimulatedBackend {
 	return backend
 }
 
+// Close terminates the underlying blockchain's update loop.
+func (b *SimulatedBackend) Close() error {
+	b.blockchain.Stop()
+	return nil
+}
+
 // Commit imports all the pending transactions as a single block and starts a
 // fresh new state.
 func (b *SimulatedBackend) Commit() {
@@ -290,8 +296,11 @@ 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.
@@ -300,8 +309,11 @@ 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
@@ -348,42 +360,70 @@ 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) {
 	// Gas prices post 1559 need to be initialized
 	if call.GasPrice != nil && (call.GasFeeCap != nil || call.GasTipCap != nil) {
-		return nil, 0, false, errors.New("both gasPrice and (maxFeePerGas or maxPriorityFeePerGas) specified")
+		return nil, errors.New("both gasPrice and (maxFeePerGas or maxPriorityFeePerGas) specified")
 	}
 	head := b.blockchain.CurrentHeader()
 	if !b.blockchain.Config().IsEIP1559(head.Number) {
@@ -438,8 +478,8 @@ func (b *SimulatedBackend) callContract(ctx context.Context, call XDPoSChain.Cal
 	vmenv := vm.NewEVM(evmContext, txContext, statedb, nil, b.config, vm.Config{NoBaseFee: true})
 	gaspool := new(core.GasPool).AddGas(math.MaxUint64)
 	owner := common.Address{}
-	ret, usedGas, failed, err, _ = core.NewStateTransition(vmenv, msg, gaspool).TransitionDb(owner)
-	return
+	res, err, _ := core.NewStateTransition(vmenv, msg, gaspool).TransitionDb(owner)
+	return res, err
 }
 
 // SendTransaction updates the pending block to include the given transaction.

accounts/abi/bind/backends/simulated_test.go

@@ -0,0 +1,154 @@
+// Copyright 2019 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package backends
+
+import (
+	"context"
+	"errors"
+	"math/big"
+	"strings"
+	"testing"
+
+	"github.com/XinFinOrg/XDPoSChain"
+	"github.com/XinFinOrg/XDPoSChain/accounts/abi"
+	"github.com/XinFinOrg/XDPoSChain/accounts/abi/bind"
+	"github.com/XinFinOrg/XDPoSChain/common"
+	"github.com/XinFinOrg/XDPoSChain/core"
+	"github.com/XinFinOrg/XDPoSChain/crypto"
+	"github.com/XinFinOrg/XDPoSChain/params"
+)
+
+func TestSimulatedBackend_EstimateGas(t *testing.T) {
+	/*
+		pragma solidity ^0.6.4;
+		contract GasEstimation {
+		    function PureRevert() public { revert(); }
+		    function Revert() public { revert("revert reason");}
+		    function OOG() public { for (uint i = 0; ; i++) {}}
+		    function Assert() public { assert(false);}
+		    function Valid() public {}
+		}*/
+	const contractAbi = "[{\"inputs\":[],\"name\":\"Assert\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"name\":\"OOG\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"name\":\"PureRevert\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"name\":\"Revert\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[],\"name\":\"Valid\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"}]"
+	const contractBin = "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"
+
+	key, _ := crypto.GenerateKey()
+	addr := crypto.PubkeyToAddress(key.PublicKey)
+	opts := bind.NewKeyedTransactor(key)
+
+	sim := NewXDCSimulatedBackend(core.GenesisAlloc{addr: {Balance: big.NewInt(params.Ether)}}, 10000000, &params.ChainConfig{
+		ConstantinopleBlock: big.NewInt(0),
+		XDPoS: &params.XDPoSConfig{
+			Epoch:            900,
+			SkipV1Validation: true,
+			V2: &params.V2{
+				SwitchBlock:   big.NewInt(900),
+				CurrentConfig: params.UnitTestV2Configs[0],
+			},
+		},
+	})
+
+	defer sim.Close()
+
+	parsed, _ := abi.JSON(strings.NewReader(contractAbi))
+	contractAddr, _, _, _ := bind.DeployContract(opts, parsed, common.FromHex(contractBin), sim)
+	sim.Commit()
+
+	var cases = []struct {
+		name        string
+		message     XDPoSChain.CallMsg
+		expect      uint64
+		expectError error
+	}{
+		{"plain transfer(valid)", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &addr,
+			Gas:      0,
+			GasPrice: big.NewInt(0),
+			Value:    big.NewInt(1),
+			Data:     nil,
+		}, params.TxGas, nil},
+
+		{"plain transfer(invalid)", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &contractAddr,
+			Gas:      0,
+			GasPrice: big.NewInt(0),
+			Value:    big.NewInt(1),
+			Data:     nil,
+		}, 0, errors.New("always failing transaction (execution reverted)")},
+
+		{"Revert", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &contractAddr,
+			Gas:      0,
+			GasPrice: big.NewInt(0),
+			Value:    nil,
+			Data:     common.Hex2Bytes("d8b98391"),
+		}, 0, errors.New("always failing transaction (execution reverted) (revert reason)")},
+
+		{"PureRevert", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &contractAddr,
+			Gas:      0,
+			GasPrice: big.NewInt(0),
+			Value:    nil,
+			Data:     common.Hex2Bytes("aa8b1d30"),
+		}, 0, errors.New("always failing transaction (execution reverted)")},
+
+		{"OOG", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &contractAddr,
+			Gas:      100000,
+			GasPrice: big.NewInt(0),
+			Value:    nil,
+			Data:     common.Hex2Bytes("50f6fe34"),
+		}, 0, errors.New("gas required exceeds allowance (100000)")},
+
+		{"Assert", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &contractAddr,
+			Gas:      100000,
+			GasPrice: big.NewInt(0),
+			Value:    nil,
+			Data:     common.Hex2Bytes("b9b046f9"),
+		}, 0, errors.New("always failing transaction (invalid opcode: INVALID)")},
+
+		{"Valid", XDPoSChain.CallMsg{
+			From:     addr,
+			To:       &contractAddr,
+			Gas:      100000,
+			GasPrice: big.NewInt(0),
+			Value:    nil,
+			Data:     common.Hex2Bytes("e09fface"),
+		}, 21483, nil},
+	}
+	for _, c := range cases {
+		got, err := sim.EstimateGas(context.Background(), c.message)
+		if c.expectError != nil {
+			if err == nil {
+				t.Fatalf("Expect error, got nil")
+			}
+			if c.expectError.Error() != err.Error() {
+				t.Fatalf("Expect error, want %v, got %v", c.expectError, err)
+			}
+			continue
+		}
+		if got != c.expect {
+			t.Fatalf("Gas estimation mismatch, want %d, got %d", c.expect, got)
+		}
+	}
+}

core/blockchain.go

@@ -82,8 +82,6 @@ var (
 	blockReorgDropMeter = metrics.NewRegisteredMeter("chain/reorg/drop", nil)
 
 	CheckpointCh = make(chan int)
-
-	ErrNoGenesis = errors.New("Genesis not found in chain")
 )
 
 const (

core/error.go

@@ -29,6 +29,18 @@ var (
 	// 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")
@@ -45,6 +57,10 @@ var (
 	// 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")
+
 	// ErrMaxInitCodeSizeExceeded is returned if creation transaction provides the init code bigger
 	// than init code size limit.
 	ErrMaxInitCodeSizeExceeded = errors.New("max initcode size exceeded")