439 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			439 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2016 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package les
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import (
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	"bytes"
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	"context"
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	"crypto/rand"
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	"fmt"
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	"math/big"
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	"reflect"
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	"testing"
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	"time"
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	"github.com/ethereum/go-ethereum/common"
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	"github.com/ethereum/go-ethereum/common/math"
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	"github.com/ethereum/go-ethereum/core"
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	"github.com/ethereum/go-ethereum/core/rawdb"
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	"github.com/ethereum/go-ethereum/core/state"
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	"github.com/ethereum/go-ethereum/core/types"
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	"github.com/ethereum/go-ethereum/core/vm"
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	"github.com/ethereum/go-ethereum/ethdb"
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	"github.com/ethereum/go-ethereum/light"
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	"github.com/ethereum/go-ethereum/params"
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	"github.com/ethereum/go-ethereum/rlp"
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)
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type odrTestFn func(ctx context.Context, db ethdb.Database, config *params.ChainConfig, bc *core.BlockChain, lc *light.LightChain, bhash common.Hash) []byte
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func TestOdrGetBlockLes2(t *testing.T) { testOdr(t, 2, 1, true, odrGetBlock) }
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func TestOdrGetBlockLes3(t *testing.T) { testOdr(t, 3, 1, true, odrGetBlock) }
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func TestOdrGetBlockLes4(t *testing.T) { testOdr(t, 4, 1, true, odrGetBlock) }
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func odrGetBlock(ctx context.Context, db ethdb.Database, config *params.ChainConfig, bc *core.BlockChain, lc *light.LightChain, bhash common.Hash) []byte {
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	var block *types.Block
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	if bc != nil {
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		block = bc.GetBlockByHash(bhash)
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	} else {
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		block, _ = lc.GetBlockByHash(ctx, bhash)
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	}
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	if block == nil {
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		return nil
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	}
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	rlp, _ := rlp.EncodeToBytes(block)
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	return rlp
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}
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func TestOdrGetReceiptsLes2(t *testing.T) { testOdr(t, 2, 1, true, odrGetReceipts) }
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func TestOdrGetReceiptsLes3(t *testing.T) { testOdr(t, 3, 1, true, odrGetReceipts) }
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func TestOdrGetReceiptsLes4(t *testing.T) { testOdr(t, 4, 1, true, odrGetReceipts) }
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func odrGetReceipts(ctx context.Context, db ethdb.Database, config *params.ChainConfig, bc *core.BlockChain, lc *light.LightChain, bhash common.Hash) []byte {
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	var receipts types.Receipts
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	if bc != nil {
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		if number := rawdb.ReadHeaderNumber(db, bhash); number != nil {
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			receipts = rawdb.ReadReceipts(db, bhash, *number, config)
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		}
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	} else {
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		if number := rawdb.ReadHeaderNumber(db, bhash); number != nil {
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			receipts, _ = light.GetBlockReceipts(ctx, lc.Odr(), bhash, *number)
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		}
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	}
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	if receipts == nil {
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		return nil
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	}
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	rlp, _ := rlp.EncodeToBytes(receipts)
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	return rlp
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}
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func TestOdrAccountsLes2(t *testing.T) { testOdr(t, 2, 1, true, odrAccounts) }
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func TestOdrAccountsLes3(t *testing.T) { testOdr(t, 3, 1, true, odrAccounts) }
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func TestOdrAccountsLes4(t *testing.T) { testOdr(t, 4, 1, true, odrAccounts) }
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func odrAccounts(ctx context.Context, db ethdb.Database, config *params.ChainConfig, bc *core.BlockChain, lc *light.LightChain, bhash common.Hash) []byte {
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	dummyAddr := common.HexToAddress("1234567812345678123456781234567812345678")
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	acc := []common.Address{bankAddr, userAddr1, userAddr2, dummyAddr}
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	var (
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		res []byte
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		st  *state.StateDB
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		err error
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	)
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	for _, addr := range acc {
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		if bc != nil {
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			header := bc.GetHeaderByHash(bhash)
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			st, err = state.New(header.Root, state.NewDatabase(db), nil)
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		} else {
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			header := lc.GetHeaderByHash(bhash)
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			st = light.NewState(ctx, header, lc.Odr())
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		}
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		if err == nil {
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			bal := st.GetBalance(addr)
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			rlp, _ := rlp.EncodeToBytes(bal)
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			res = append(res, rlp...)
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		}
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	}
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	return res
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}
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func TestOdrContractCallLes2(t *testing.T) { testOdr(t, 2, 2, true, odrContractCall) }
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func TestOdrContractCallLes3(t *testing.T) { testOdr(t, 3, 2, true, odrContractCall) }
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func TestOdrContractCallLes4(t *testing.T) { testOdr(t, 4, 2, true, odrContractCall) }
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type callmsg struct {
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	types.Message
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}
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func (callmsg) CheckNonce() bool { return false }
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func odrContractCall(ctx context.Context, db ethdb.Database, config *params.ChainConfig, bc *core.BlockChain, lc *light.LightChain, bhash common.Hash) []byte {
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	data := common.Hex2Bytes("60CD26850000000000000000000000000000000000000000000000000000000000000000")
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	var res []byte
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	for i := 0; i < 3; i++ {
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		data[35] = byte(i)
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		if bc != nil {
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			header := bc.GetHeaderByHash(bhash)
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			statedb, err := state.New(header.Root, state.NewDatabase(db), nil)
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			if err == nil {
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				from := statedb.GetOrNewStateObject(bankAddr)
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				from.SetBalance(math.MaxBig256)
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				msg := callmsg{types.NewMessage(from.Address(), &testContractAddr, 0, new(big.Int), 100000, big.NewInt(params.InitialBaseFee), big.NewInt(params.InitialBaseFee), new(big.Int), data, nil, true)}
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				context := core.NewEVMBlockContext(header, bc, nil)
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				txContext := core.NewEVMTxContext(msg)
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				vmenv := vm.NewEVM(context, txContext, statedb, config, vm.Config{NoBaseFee: true})
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				//vmenv := core.NewEnv(statedb, config, bc, msg, header, vm.Config{})
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				gp := new(core.GasPool).AddGas(math.MaxUint64)
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				result, _ := core.ApplyMessage(vmenv, msg, gp)
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				res = append(res, result.Return()...)
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			}
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		} else {
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			header := lc.GetHeaderByHash(bhash)
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			state := light.NewState(ctx, header, lc.Odr())
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			state.SetBalance(bankAddr, math.MaxBig256)
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			msg := callmsg{types.NewMessage(bankAddr, &testContractAddr, 0, new(big.Int), 100000, big.NewInt(params.InitialBaseFee), big.NewInt(params.InitialBaseFee), new(big.Int), data, nil, true)}
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			context := core.NewEVMBlockContext(header, lc, nil)
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			txContext := core.NewEVMTxContext(msg)
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			vmenv := vm.NewEVM(context, txContext, state, config, vm.Config{NoBaseFee: true})
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			gp := new(core.GasPool).AddGas(math.MaxUint64)
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			result, _ := core.ApplyMessage(vmenv, msg, gp)
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			if state.Error() == nil {
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				res = append(res, result.Return()...)
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			}
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		}
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	}
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	return res
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}
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func TestOdrTxStatusLes2(t *testing.T) { testOdr(t, 2, 1, false, odrTxStatus) }
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func TestOdrTxStatusLes3(t *testing.T) { testOdr(t, 3, 1, false, odrTxStatus) }
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func TestOdrTxStatusLes4(t *testing.T) { testOdr(t, 4, 1, false, odrTxStatus) }
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func odrTxStatus(ctx context.Context, db ethdb.Database, config *params.ChainConfig, bc *core.BlockChain, lc *light.LightChain, bhash common.Hash) []byte {
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	var txs types.Transactions
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	if bc != nil {
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		block := bc.GetBlockByHash(bhash)
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		txs = block.Transactions()
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	} else {
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		if block, _ := lc.GetBlockByHash(ctx, bhash); block != nil {
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			btxs := block.Transactions()
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			txs = make(types.Transactions, len(btxs))
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			for i, tx := range btxs {
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				var err error
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				txs[i], _, _, _, err = light.GetTransaction(ctx, lc.Odr(), tx.Hash())
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				if err != nil {
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					return nil
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				}
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			}
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		}
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	}
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	rlp, _ := rlp.EncodeToBytes(txs)
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	return rlp
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}
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// testOdr tests odr requests whose validation guaranteed by block headers.
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func testOdr(t *testing.T, protocol int, expFail uint64, checkCached bool, fn odrTestFn) {
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	// Assemble the test environment
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	netconfig := testnetConfig{
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		blocks:    4,
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		protocol:  protocol,
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		connect:   true,
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		nopruning: true,
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	}
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	server, client, tearDown := newClientServerEnv(t, netconfig)
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	defer tearDown()
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	// Ensure the client has synced all necessary data.
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	clientHead := client.handler.backend.blockchain.CurrentHeader()
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	if clientHead.Number.Uint64() != 4 {
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		t.Fatalf("Failed to sync the chain with server, head: %v", clientHead.Number.Uint64())
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	}
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	// Disable the mechanism that we will wait a few time for request
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	// even there is no suitable peer to send right now.
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	waitForPeers = 0
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	test := func(expFail uint64) {
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		// Mark this as a helper to put the failures at the correct lines
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		t.Helper()
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		for i := uint64(0); i <= server.handler.blockchain.CurrentHeader().Number.Uint64(); i++ {
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			bhash := rawdb.ReadCanonicalHash(server.db, i)
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			b1 := fn(light.NoOdr, server.db, server.handler.server.chainConfig, server.handler.blockchain, nil, bhash)
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			// Set the timeout as 1 second here, ensure there is enough time
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			// for travis to make the action.
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			ctx, cancel := context.WithTimeout(context.Background(), time.Second)
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			b2 := fn(ctx, client.db, client.handler.backend.chainConfig, nil, client.handler.backend.blockchain, bhash)
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			cancel()
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			eq := bytes.Equal(b1, b2)
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			exp := i < expFail
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			if exp && !eq {
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				t.Fatalf("odr mismatch: have %x, want %x", b2, b1)
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			}
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			if !exp && eq {
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				t.Fatalf("unexpected odr match")
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			}
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		}
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	}
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	// expect retrievals to fail (except genesis block) without a les peer
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	client.handler.backend.peers.lock.Lock()
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	client.peer.speer.hasBlockHook = func(common.Hash, uint64, bool) bool { return false }
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	client.handler.backend.peers.lock.Unlock()
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	test(expFail)
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	// expect all retrievals to pass
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	client.handler.backend.peers.lock.Lock()
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	client.peer.speer.hasBlockHook = func(common.Hash, uint64, bool) bool { return true }
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	client.handler.backend.peers.lock.Unlock()
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	test(5)
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	// still expect all retrievals to pass, now data should be cached locally
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	if checkCached {
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		client.handler.backend.peers.unregister(client.peer.speer.id)
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		time.Sleep(time.Millisecond * 10) // ensure that all peerSetNotify callbacks are executed
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		test(5)
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	}
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}
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func TestGetTxStatusFromUnindexedPeersLES4(t *testing.T) { testGetTxStatusFromUnindexedPeers(t, lpv4) }
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func testGetTxStatusFromUnindexedPeers(t *testing.T, protocol int) {
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	var (
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		blocks    = 8
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		netconfig = testnetConfig{
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			blocks:    blocks,
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			protocol:  protocol,
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			nopruning: true,
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		}
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	)
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	server, client, tearDown := newClientServerEnv(t, netconfig)
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	defer tearDown()
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	// Iterate the chain, create the tx indexes locally
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	var (
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		testHash   common.Hash
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		testStatus light.TxStatus
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		txs          = make(map[common.Hash]*types.Transaction) // Transaction objects set
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		blockNumbers = make(map[common.Hash]uint64)             // Transaction hash to block number mappings
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		blockHashes  = make(map[common.Hash]common.Hash)        // Transaction hash to block hash mappings
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		intraIndex   = make(map[common.Hash]uint64)             // Transaction intra-index in block
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	)
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	for number := uint64(1); number < server.backend.Blockchain().CurrentBlock().NumberU64(); number++ {
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		block := server.backend.Blockchain().GetBlockByNumber(number)
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		if block == nil {
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			t.Fatalf("Failed to retrieve block %d", number)
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		}
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		for index, tx := range block.Transactions() {
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			txs[tx.Hash()] = tx
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			blockNumbers[tx.Hash()] = number
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			blockHashes[tx.Hash()] = block.Hash()
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			intraIndex[tx.Hash()] = uint64(index)
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			if testHash == (common.Hash{}) {
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				testHash = tx.Hash()
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				testStatus = light.TxStatus{
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					Status: core.TxStatusIncluded,
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					Lookup: &rawdb.LegacyTxLookupEntry{
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						BlockHash:  block.Hash(),
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						BlockIndex: block.NumberU64(),
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						Index:      uint64(index),
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					},
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				}
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			}
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		}
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	}
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	// serveMsg processes incoming GetTxStatusMsg and sends the response back.
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	serveMsg := func(peer *testPeer, txLookup uint64) error {
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		msg, err := peer.app.ReadMsg()
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		if err != nil {
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			return err
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		}
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		if msg.Code != GetTxStatusMsg {
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			return fmt.Errorf("message code mismatch: got %d, expected %d", msg.Code, GetTxStatusMsg)
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		}
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		var r GetTxStatusPacket
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		if err := msg.Decode(&r); err != nil {
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			return err
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		}
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		stats := make([]light.TxStatus, len(r.Hashes))
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		for i, hash := range r.Hashes {
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			number, exist := blockNumbers[hash]
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			if !exist {
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				continue // Filter out unknown transactions
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			}
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			min := uint64(blocks) - txLookup
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			if txLookup != txIndexUnlimited && (txLookup == txIndexDisabled || number < min) {
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				continue // Filter out unindexed transactions
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			}
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			stats[i].Status = core.TxStatusIncluded
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			stats[i].Lookup = &rawdb.LegacyTxLookupEntry{
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				BlockHash:  blockHashes[hash],
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				BlockIndex: number,
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				Index:      intraIndex[hash],
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			}
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		}
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		data, _ := rlp.EncodeToBytes(stats)
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		reply := &reply{peer.app, TxStatusMsg, r.ReqID, data}
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		reply.send(testBufLimit)
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		return nil
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	}
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	var testspecs = []struct {
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		peers     int
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		txLookups []uint64
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		txs       []common.Hash
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		results   []light.TxStatus
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	}{
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		// Retrieve mined transaction from the empty peerset
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		{
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			peers:     0,
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			txLookups: []uint64{},
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			txs:       []common.Hash{testHash},
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			results:   []light.TxStatus{{}},
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		},
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		// Retrieve unknown transaction from the full peers
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		{
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			peers:     3,
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			txLookups: []uint64{txIndexUnlimited, txIndexUnlimited, txIndexUnlimited},
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			txs:       []common.Hash{randomHash()},
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			results:   []light.TxStatus{{}},
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		},
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		// Retrieve mined transaction from the full peers
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		{
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			peers:     3,
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			txLookups: []uint64{txIndexUnlimited, txIndexUnlimited, txIndexUnlimited},
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			txs:       []common.Hash{testHash},
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			results:   []light.TxStatus{testStatus},
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		},
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		// Retrieve mixed transactions from the full peers
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		{
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			peers:     3,
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			txLookups: []uint64{txIndexUnlimited, txIndexUnlimited, txIndexUnlimited},
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			txs:       []common.Hash{randomHash(), testHash},
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						|
			results:   []light.TxStatus{{}, testStatus},
 | 
						|
		},
 | 
						|
		// Retrieve mixed transactions from unindexed peer(but the target is still available)
 | 
						|
		{
 | 
						|
			peers:     3,
 | 
						|
			txLookups: []uint64{uint64(blocks) - testStatus.Lookup.BlockIndex, uint64(blocks) - testStatus.Lookup.BlockIndex - 1, uint64(blocks) - testStatus.Lookup.BlockIndex - 2},
 | 
						|
			txs:       []common.Hash{randomHash(), testHash},
 | 
						|
			results:   []light.TxStatus{{}, testStatus},
 | 
						|
		},
 | 
						|
		// Retrieve mixed transactions from unindexed peer(but the target is not available)
 | 
						|
		{
 | 
						|
			peers:     3,
 | 
						|
			txLookups: []uint64{uint64(blocks) - testStatus.Lookup.BlockIndex - 1, uint64(blocks) - testStatus.Lookup.BlockIndex - 1, uint64(blocks) - testStatus.Lookup.BlockIndex - 2},
 | 
						|
			txs:       []common.Hash{randomHash(), testHash},
 | 
						|
			results:   []light.TxStatus{{}, {}},
 | 
						|
		},
 | 
						|
	}
 | 
						|
	for _, testspec := range testspecs {
 | 
						|
		// Create a bunch of server peers with different tx history
 | 
						|
		var (
 | 
						|
			serverPeers []*testPeer
 | 
						|
			closeFns    []func()
 | 
						|
		)
 | 
						|
		for i := 0; i < testspec.peers; i++ {
 | 
						|
			peer, closePeer, _ := client.newRawPeer(t, fmt.Sprintf("server-%d", i), protocol, testspec.txLookups[i])
 | 
						|
			serverPeers = append(serverPeers, peer)
 | 
						|
			closeFns = append(closeFns, closePeer)
 | 
						|
 | 
						|
			// Create a one-time routine for serving message
 | 
						|
			go func(i int, peer *testPeer, lookup uint64) {
 | 
						|
				serveMsg(peer, lookup)
 | 
						|
			}(i, peer, testspec.txLookups[i])
 | 
						|
		}
 | 
						|
 | 
						|
		// Send out the GetTxStatus requests, compare the result with
 | 
						|
		// expected value.
 | 
						|
		r := &light.TxStatusRequest{Hashes: testspec.txs}
 | 
						|
		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
 | 
						|
		defer cancel()
 | 
						|
 | 
						|
		err := client.handler.backend.odr.RetrieveTxStatus(ctx, r)
 | 
						|
		if err != nil {
 | 
						|
			t.Errorf("Failed to retrieve tx status %v", err)
 | 
						|
		} else {
 | 
						|
			if !reflect.DeepEqual(testspec.results, r.Status) {
 | 
						|
				t.Errorf("Result mismatch, diff")
 | 
						|
			}
 | 
						|
		}
 | 
						|
 | 
						|
		// Close all connected peers and start the next round
 | 
						|
		for _, closeFn := range closeFns {
 | 
						|
			closeFn()
 | 
						|
		}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// randomHash generates a random blob of data and returns it as a hash.
 | 
						|
func randomHash() common.Hash {
 | 
						|
	var hash common.Hash
 | 
						|
	if n, err := rand.Read(hash[:]); n != common.HashLength || err != nil {
 | 
						|
		panic(err)
 | 
						|
	}
 | 
						|
	return hash
 | 
						|
}
 |