github.com/LampardNguyen234/go-ethereum@v1.10.16-0.20220117140830-b6a3b0260724/eth/tracers/api_test.go (about)

     1  // Copyright 2021 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package tracers
    18  
    19  import (
    20  	"bytes"
    21  	"context"
    22  	"crypto/ecdsa"
    23  	"encoding/json"
    24  	"errors"
    25  	"fmt"
    26  	"math/big"
    27  	"reflect"
    28  	"sort"
    29  	"testing"
    30  	"time"
    31  
    32  	"github.com/LampardNguyen234/go-ethereum/common"
    33  	"github.com/LampardNguyen234/go-ethereum/common/hexutil"
    34  	"github.com/LampardNguyen234/go-ethereum/consensus"
    35  	"github.com/LampardNguyen234/go-ethereum/consensus/ethash"
    36  	"github.com/LampardNguyen234/go-ethereum/core"
    37  	"github.com/LampardNguyen234/go-ethereum/core/rawdb"
    38  	"github.com/LampardNguyen234/go-ethereum/core/state"
    39  	"github.com/LampardNguyen234/go-ethereum/core/types"
    40  	"github.com/LampardNguyen234/go-ethereum/core/vm"
    41  	"github.com/LampardNguyen234/go-ethereum/crypto"
    42  	"github.com/LampardNguyen234/go-ethereum/ethdb"
    43  	"github.com/LampardNguyen234/go-ethereum/internal/ethapi"
    44  	"github.com/LampardNguyen234/go-ethereum/params"
    45  	"github.com/LampardNguyen234/go-ethereum/rpc"
    46  )
    47  
    48  var (
    49  	errStateNotFound       = errors.New("state not found")
    50  	errBlockNotFound       = errors.New("block not found")
    51  	errTransactionNotFound = errors.New("transaction not found")
    52  )
    53  
    54  type testBackend struct {
    55  	chainConfig *params.ChainConfig
    56  	engine      consensus.Engine
    57  	chaindb     ethdb.Database
    58  	chain       *core.BlockChain
    59  }
    60  
    61  func newTestBackend(t *testing.T, n int, gspec *core.Genesis, generator func(i int, b *core.BlockGen)) *testBackend {
    62  	backend := &testBackend{
    63  		chainConfig: params.TestChainConfig,
    64  		engine:      ethash.NewFaker(),
    65  		chaindb:     rawdb.NewMemoryDatabase(),
    66  	}
    67  	// Generate blocks for testing
    68  	gspec.Config = backend.chainConfig
    69  	var (
    70  		gendb   = rawdb.NewMemoryDatabase()
    71  		genesis = gspec.MustCommit(gendb)
    72  	)
    73  	blocks, _ := core.GenerateChain(backend.chainConfig, genesis, backend.engine, gendb, n, generator)
    74  
    75  	// Import the canonical chain
    76  	gspec.MustCommit(backend.chaindb)
    77  	cacheConfig := &core.CacheConfig{
    78  		TrieCleanLimit:    256,
    79  		TrieDirtyLimit:    256,
    80  		TrieTimeLimit:     5 * time.Minute,
    81  		SnapshotLimit:     0,
    82  		TrieDirtyDisabled: true, // Archive mode
    83  	}
    84  	chain, err := core.NewBlockChain(backend.chaindb, cacheConfig, backend.chainConfig, backend.engine, vm.Config{}, nil, nil)
    85  	if err != nil {
    86  		t.Fatalf("failed to create tester chain: %v", err)
    87  	}
    88  	if n, err := chain.InsertChain(blocks); err != nil {
    89  		t.Fatalf("block %d: failed to insert into chain: %v", n, err)
    90  	}
    91  	backend.chain = chain
    92  	return backend
    93  }
    94  
    95  func (b *testBackend) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) {
    96  	return b.chain.GetHeaderByHash(hash), nil
    97  }
    98  
    99  func (b *testBackend) HeaderByNumber(ctx context.Context, number rpc.BlockNumber) (*types.Header, error) {
   100  	if number == rpc.PendingBlockNumber || number == rpc.LatestBlockNumber {
   101  		return b.chain.CurrentHeader(), nil
   102  	}
   103  	return b.chain.GetHeaderByNumber(uint64(number)), nil
   104  }
   105  
   106  func (b *testBackend) BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error) {
   107  	return b.chain.GetBlockByHash(hash), nil
   108  }
   109  
   110  func (b *testBackend) BlockByNumber(ctx context.Context, number rpc.BlockNumber) (*types.Block, error) {
   111  	if number == rpc.PendingBlockNumber || number == rpc.LatestBlockNumber {
   112  		return b.chain.CurrentBlock(), nil
   113  	}
   114  	return b.chain.GetBlockByNumber(uint64(number)), nil
   115  }
   116  
   117  func (b *testBackend) GetTransaction(ctx context.Context, txHash common.Hash) (*types.Transaction, common.Hash, uint64, uint64, error) {
   118  	tx, hash, blockNumber, index := rawdb.ReadTransaction(b.chaindb, txHash)
   119  	if tx == nil {
   120  		return nil, common.Hash{}, 0, 0, errTransactionNotFound
   121  	}
   122  	return tx, hash, blockNumber, index, nil
   123  }
   124  
   125  func (b *testBackend) RPCGasCap() uint64 {
   126  	return 25000000
   127  }
   128  
   129  func (b *testBackend) ChainConfig() *params.ChainConfig {
   130  	return b.chainConfig
   131  }
   132  
   133  func (b *testBackend) Engine() consensus.Engine {
   134  	return b.engine
   135  }
   136  
   137  func (b *testBackend) ChainDb() ethdb.Database {
   138  	return b.chaindb
   139  }
   140  
   141  func (b *testBackend) StateAtBlock(ctx context.Context, block *types.Block, reexec uint64, base *state.StateDB, checkLive bool, preferDisk bool) (*state.StateDB, error) {
   142  	statedb, err := b.chain.StateAt(block.Root())
   143  	if err != nil {
   144  		return nil, errStateNotFound
   145  	}
   146  	return statedb, nil
   147  }
   148  
   149  func (b *testBackend) StateAtTransaction(ctx context.Context, block *types.Block, txIndex int, reexec uint64) (core.Message, vm.BlockContext, *state.StateDB, error) {
   150  	parent := b.chain.GetBlock(block.ParentHash(), block.NumberU64()-1)
   151  	if parent == nil {
   152  		return nil, vm.BlockContext{}, nil, errBlockNotFound
   153  	}
   154  	statedb, err := b.chain.StateAt(parent.Root())
   155  	if err != nil {
   156  		return nil, vm.BlockContext{}, nil, errStateNotFound
   157  	}
   158  	if txIndex == 0 && len(block.Transactions()) == 0 {
   159  		return nil, vm.BlockContext{}, statedb, nil
   160  	}
   161  	// Recompute transactions up to the target index.
   162  	signer := types.MakeSigner(b.chainConfig, block.Number())
   163  	for idx, tx := range block.Transactions() {
   164  		msg, _ := tx.AsMessage(signer, block.BaseFee())
   165  		txContext := core.NewEVMTxContext(msg)
   166  		context := core.NewEVMBlockContext(block.Header(), b.chain, nil)
   167  		if idx == txIndex {
   168  			return msg, context, statedb, nil
   169  		}
   170  		vmenv := vm.NewEVM(context, txContext, statedb, b.chainConfig, vm.Config{})
   171  		if _, err := core.ApplyMessage(vmenv, msg, new(core.GasPool).AddGas(tx.Gas())); err != nil {
   172  			return nil, vm.BlockContext{}, nil, fmt.Errorf("transaction %#x failed: %v", tx.Hash(), err)
   173  		}
   174  		statedb.Finalise(vmenv.ChainConfig().IsEIP158(block.Number()))
   175  	}
   176  	return nil, vm.BlockContext{}, nil, fmt.Errorf("transaction index %d out of range for block %#x", txIndex, block.Hash())
   177  }
   178  
   179  func TestTraceCall(t *testing.T) {
   180  	t.Parallel()
   181  
   182  	// Initialize test accounts
   183  	accounts := newAccounts(3)
   184  	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
   185  		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
   186  		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
   187  		accounts[2].addr: {Balance: big.NewInt(params.Ether)},
   188  	}}
   189  	genBlocks := 10
   190  	signer := types.HomesteadSigner{}
   191  	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
   192  		// Transfer from account[0] to account[1]
   193  		//    value: 1000 wei
   194  		//    fee:   0 wei
   195  		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
   196  		b.AddTx(tx)
   197  	}))
   198  
   199  	var testSuite = []struct {
   200  		blockNumber rpc.BlockNumber
   201  		call        ethapi.TransactionArgs
   202  		config      *TraceCallConfig
   203  		expectErr   error
   204  		expect      interface{}
   205  	}{
   206  		// Standard JSON trace upon the genesis, plain transfer.
   207  		{
   208  			blockNumber: rpc.BlockNumber(0),
   209  			call: ethapi.TransactionArgs{
   210  				From:  &accounts[0].addr,
   211  				To:    &accounts[1].addr,
   212  				Value: (*hexutil.Big)(big.NewInt(1000)),
   213  			},
   214  			config:    nil,
   215  			expectErr: nil,
   216  			expect: &ethapi.ExecutionResult{
   217  				Gas:         params.TxGas,
   218  				Failed:      false,
   219  				ReturnValue: "",
   220  				StructLogs:  []ethapi.StructLogRes{},
   221  			},
   222  		},
   223  		// Standard JSON trace upon the head, plain transfer.
   224  		{
   225  			blockNumber: rpc.BlockNumber(genBlocks),
   226  			call: ethapi.TransactionArgs{
   227  				From:  &accounts[0].addr,
   228  				To:    &accounts[1].addr,
   229  				Value: (*hexutil.Big)(big.NewInt(1000)),
   230  			},
   231  			config:    nil,
   232  			expectErr: nil,
   233  			expect: &ethapi.ExecutionResult{
   234  				Gas:         params.TxGas,
   235  				Failed:      false,
   236  				ReturnValue: "",
   237  				StructLogs:  []ethapi.StructLogRes{},
   238  			},
   239  		},
   240  		// Standard JSON trace upon the non-existent block, error expects
   241  		{
   242  			blockNumber: rpc.BlockNumber(genBlocks + 1),
   243  			call: ethapi.TransactionArgs{
   244  				From:  &accounts[0].addr,
   245  				To:    &accounts[1].addr,
   246  				Value: (*hexutil.Big)(big.NewInt(1000)),
   247  			},
   248  			config:    nil,
   249  			expectErr: fmt.Errorf("block #%d not found", genBlocks+1),
   250  			expect:    nil,
   251  		},
   252  		// Standard JSON trace upon the latest block
   253  		{
   254  			blockNumber: rpc.LatestBlockNumber,
   255  			call: ethapi.TransactionArgs{
   256  				From:  &accounts[0].addr,
   257  				To:    &accounts[1].addr,
   258  				Value: (*hexutil.Big)(big.NewInt(1000)),
   259  			},
   260  			config:    nil,
   261  			expectErr: nil,
   262  			expect: &ethapi.ExecutionResult{
   263  				Gas:         params.TxGas,
   264  				Failed:      false,
   265  				ReturnValue: "",
   266  				StructLogs:  []ethapi.StructLogRes{},
   267  			},
   268  		},
   269  		// Standard JSON trace upon the pending block
   270  		{
   271  			blockNumber: rpc.PendingBlockNumber,
   272  			call: ethapi.TransactionArgs{
   273  				From:  &accounts[0].addr,
   274  				To:    &accounts[1].addr,
   275  				Value: (*hexutil.Big)(big.NewInt(1000)),
   276  			},
   277  			config:    nil,
   278  			expectErr: nil,
   279  			expect: &ethapi.ExecutionResult{
   280  				Gas:         params.TxGas,
   281  				Failed:      false,
   282  				ReturnValue: "",
   283  				StructLogs:  []ethapi.StructLogRes{},
   284  			},
   285  		},
   286  	}
   287  	for _, testspec := range testSuite {
   288  		result, err := api.TraceCall(context.Background(), testspec.call, rpc.BlockNumberOrHash{BlockNumber: &testspec.blockNumber}, testspec.config)
   289  		if testspec.expectErr != nil {
   290  			if err == nil {
   291  				t.Errorf("Expect error %v, get nothing", testspec.expectErr)
   292  				continue
   293  			}
   294  			if !reflect.DeepEqual(err, testspec.expectErr) {
   295  				t.Errorf("Error mismatch, want %v, get %v", testspec.expectErr, err)
   296  			}
   297  		} else {
   298  			if err != nil {
   299  				t.Errorf("Expect no error, get %v", err)
   300  				continue
   301  			}
   302  			if !reflect.DeepEqual(result, testspec.expect) {
   303  				t.Errorf("Result mismatch, want %v, get %v", testspec.expect, result)
   304  			}
   305  		}
   306  	}
   307  }
   308  
   309  func TestTraceTransaction(t *testing.T) {
   310  	t.Parallel()
   311  
   312  	// Initialize test accounts
   313  	accounts := newAccounts(2)
   314  	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
   315  		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
   316  		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
   317  	}}
   318  	target := common.Hash{}
   319  	signer := types.HomesteadSigner{}
   320  	api := NewAPI(newTestBackend(t, 1, genesis, func(i int, b *core.BlockGen) {
   321  		// Transfer from account[0] to account[1]
   322  		//    value: 1000 wei
   323  		//    fee:   0 wei
   324  		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
   325  		b.AddTx(tx)
   326  		target = tx.Hash()
   327  	}))
   328  	result, err := api.TraceTransaction(context.Background(), target, nil)
   329  	if err != nil {
   330  		t.Errorf("Failed to trace transaction %v", err)
   331  	}
   332  	if !reflect.DeepEqual(result, &ethapi.ExecutionResult{
   333  		Gas:         params.TxGas,
   334  		Failed:      false,
   335  		ReturnValue: "",
   336  		StructLogs:  []ethapi.StructLogRes{},
   337  	}) {
   338  		t.Error("Transaction tracing result is different")
   339  	}
   340  }
   341  
   342  func TestTraceBlock(t *testing.T) {
   343  	t.Parallel()
   344  
   345  	// Initialize test accounts
   346  	accounts := newAccounts(3)
   347  	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
   348  		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
   349  		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
   350  		accounts[2].addr: {Balance: big.NewInt(params.Ether)},
   351  	}}
   352  	genBlocks := 10
   353  	signer := types.HomesteadSigner{}
   354  	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
   355  		// Transfer from account[0] to account[1]
   356  		//    value: 1000 wei
   357  		//    fee:   0 wei
   358  		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
   359  		b.AddTx(tx)
   360  	}))
   361  
   362  	var testSuite = []struct {
   363  		blockNumber rpc.BlockNumber
   364  		config      *TraceConfig
   365  		want        string
   366  		expectErr   error
   367  	}{
   368  		// Trace genesis block, expect error
   369  		{
   370  			blockNumber: rpc.BlockNumber(0),
   371  			expectErr:   errors.New("genesis is not traceable"),
   372  		},
   373  		// Trace head block
   374  		{
   375  			blockNumber: rpc.BlockNumber(genBlocks),
   376  			want:        `[{"result":{"gas":21000,"failed":false,"returnValue":"","structLogs":[]}}]`,
   377  		},
   378  		// Trace non-existent block
   379  		{
   380  			blockNumber: rpc.BlockNumber(genBlocks + 1),
   381  			expectErr:   fmt.Errorf("block #%d not found", genBlocks+1),
   382  		},
   383  		// Trace latest block
   384  		{
   385  			blockNumber: rpc.LatestBlockNumber,
   386  			want:        `[{"result":{"gas":21000,"failed":false,"returnValue":"","structLogs":[]}}]`,
   387  		},
   388  		// Trace pending block
   389  		{
   390  			blockNumber: rpc.PendingBlockNumber,
   391  			want:        `[{"result":{"gas":21000,"failed":false,"returnValue":"","structLogs":[]}}]`,
   392  		},
   393  	}
   394  	for i, tc := range testSuite {
   395  		result, err := api.TraceBlockByNumber(context.Background(), tc.blockNumber, tc.config)
   396  		if tc.expectErr != nil {
   397  			if err == nil {
   398  				t.Errorf("test %d, want error %v", i, tc.expectErr)
   399  				continue
   400  			}
   401  			if !reflect.DeepEqual(err, tc.expectErr) {
   402  				t.Errorf("test %d: error mismatch, want %v, get %v", i, tc.expectErr, err)
   403  			}
   404  			continue
   405  		}
   406  		if err != nil {
   407  			t.Errorf("test %d, want no error, have %v", i, err)
   408  			continue
   409  		}
   410  		have, _ := json.Marshal(result)
   411  		want := tc.want
   412  		if string(have) != want {
   413  			t.Errorf("test %d, result mismatch, have\n%v\n, want\n%v\n", i, string(have), want)
   414  		}
   415  	}
   416  }
   417  
   418  func TestTracingWithOverrides(t *testing.T) {
   419  	t.Parallel()
   420  	// Initialize test accounts
   421  	accounts := newAccounts(3)
   422  	genesis := &core.Genesis{Alloc: core.GenesisAlloc{
   423  		accounts[0].addr: {Balance: big.NewInt(params.Ether)},
   424  		accounts[1].addr: {Balance: big.NewInt(params.Ether)},
   425  		accounts[2].addr: {Balance: big.NewInt(params.Ether)},
   426  	}}
   427  	genBlocks := 10
   428  	signer := types.HomesteadSigner{}
   429  	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
   430  		// Transfer from account[0] to account[1]
   431  		//    value: 1000 wei
   432  		//    fee:   0 wei
   433  		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
   434  		b.AddTx(tx)
   435  	}))
   436  	randomAccounts := newAccounts(3)
   437  	type res struct {
   438  		Gas         int
   439  		Failed      bool
   440  		returnValue string
   441  	}
   442  	var testSuite = []struct {
   443  		blockNumber rpc.BlockNumber
   444  		call        ethapi.TransactionArgs
   445  		config      *TraceCallConfig
   446  		expectErr   error
   447  		want        string
   448  	}{
   449  		// Call which can only succeed if state is state overridden
   450  		{
   451  			blockNumber: rpc.PendingBlockNumber,
   452  			call: ethapi.TransactionArgs{
   453  				From:  &randomAccounts[0].addr,
   454  				To:    &randomAccounts[1].addr,
   455  				Value: (*hexutil.Big)(big.NewInt(1000)),
   456  			},
   457  			config: &TraceCallConfig{
   458  				StateOverrides: &ethapi.StateOverride{
   459  					randomAccounts[0].addr: ethapi.OverrideAccount{Balance: newRPCBalance(new(big.Int).Mul(big.NewInt(1), big.NewInt(params.Ether)))},
   460  				},
   461  			},
   462  			want: `{"gas":21000,"failed":false,"returnValue":""}`,
   463  		},
   464  		// Invalid call without state overriding
   465  		{
   466  			blockNumber: rpc.PendingBlockNumber,
   467  			call: ethapi.TransactionArgs{
   468  				From:  &randomAccounts[0].addr,
   469  				To:    &randomAccounts[1].addr,
   470  				Value: (*hexutil.Big)(big.NewInt(1000)),
   471  			},
   472  			config:    &TraceCallConfig{},
   473  			expectErr: core.ErrInsufficientFunds,
   474  		},
   475  		// Successful simple contract call
   476  		//
   477  		// // SPDX-License-Identifier: GPL-3.0
   478  		//
   479  		//  pragma solidity >=0.7.0 <0.8.0;
   480  		//
   481  		//  /**
   482  		//   * @title Storage
   483  		//   * @dev Store & retrieve value in a variable
   484  		//   */
   485  		//  contract Storage {
   486  		//      uint256 public number;
   487  		//      constructor() {
   488  		//          number = block.number;
   489  		//      }
   490  		//  }
   491  		{
   492  			blockNumber: rpc.PendingBlockNumber,
   493  			call: ethapi.TransactionArgs{
   494  				From: &randomAccounts[0].addr,
   495  				To:   &randomAccounts[2].addr,
   496  				Data: newRPCBytes(common.Hex2Bytes("8381f58a")), // call number()
   497  			},
   498  			config: &TraceCallConfig{
   499  				//Tracer: &tracer,
   500  				StateOverrides: &ethapi.StateOverride{
   501  					randomAccounts[2].addr: ethapi.OverrideAccount{
   502  						Code:      newRPCBytes(common.Hex2Bytes("6080604052348015600f57600080fd5b506004361060285760003560e01c80638381f58a14602d575b600080fd5b60336049565b6040518082815260200191505060405180910390f35b6000548156fea2646970667358221220eab35ffa6ab2adfe380772a48b8ba78e82a1b820a18fcb6f59aa4efb20a5f60064736f6c63430007040033")),
   503  						StateDiff: newStates([]common.Hash{{}}, []common.Hash{common.BigToHash(big.NewInt(123))}),
   504  					},
   505  				},
   506  			},
   507  			want: `{"gas":23347,"failed":false,"returnValue":"000000000000000000000000000000000000000000000000000000000000007b"}`,
   508  		},
   509  	}
   510  	for i, tc := range testSuite {
   511  		result, err := api.TraceCall(context.Background(), tc.call, rpc.BlockNumberOrHash{BlockNumber: &tc.blockNumber}, tc.config)
   512  		if tc.expectErr != nil {
   513  			if err == nil {
   514  				t.Errorf("test %d: want error %v, have nothing", i, tc.expectErr)
   515  				continue
   516  			}
   517  			if !errors.Is(err, tc.expectErr) {
   518  				t.Errorf("test %d: error mismatch, want %v, have %v", i, tc.expectErr, err)
   519  			}
   520  			continue
   521  		}
   522  		if err != nil {
   523  			t.Errorf("test %d: want no error, have %v", i, err)
   524  			continue
   525  		}
   526  		// Turn result into res-struct
   527  		var (
   528  			have res
   529  			want res
   530  		)
   531  		resBytes, _ := json.Marshal(result)
   532  		json.Unmarshal(resBytes, &have)
   533  		json.Unmarshal([]byte(tc.want), &want)
   534  		if !reflect.DeepEqual(have, want) {
   535  			t.Errorf("test %d, result mismatch, have\n%v\n, want\n%v\n", i, string(resBytes), want)
   536  		}
   537  	}
   538  }
   539  
   540  type Account struct {
   541  	key  *ecdsa.PrivateKey
   542  	addr common.Address
   543  }
   544  
   545  type Accounts []Account
   546  
   547  func (a Accounts) Len() int           { return len(a) }
   548  func (a Accounts) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
   549  func (a Accounts) Less(i, j int) bool { return bytes.Compare(a[i].addr.Bytes(), a[j].addr.Bytes()) < 0 }
   550  
   551  func newAccounts(n int) (accounts Accounts) {
   552  	for i := 0; i < n; i++ {
   553  		key, _ := crypto.GenerateKey()
   554  		addr := crypto.PubkeyToAddress(key.PublicKey)
   555  		accounts = append(accounts, Account{key: key, addr: addr})
   556  	}
   557  	sort.Sort(accounts)
   558  	return accounts
   559  }
   560  
   561  func newRPCBalance(balance *big.Int) **hexutil.Big {
   562  	rpcBalance := (*hexutil.Big)(balance)
   563  	return &rpcBalance
   564  }
   565  
   566  func newRPCBytes(bytes []byte) *hexutil.Bytes {
   567  	rpcBytes := hexutil.Bytes(bytes)
   568  	return &rpcBytes
   569  }
   570  
   571  func newStates(keys []common.Hash, vals []common.Hash) *map[common.Hash]common.Hash {
   572  	if len(keys) != len(vals) {
   573  		panic("invalid input")
   574  	}
   575  	m := make(map[common.Hash]common.Hash)
   576  	for i := 0; i < len(keys); i++ {
   577  		m[keys[i]] = vals[i]
   578  	}
   579  	return &m
   580  }