How to run instrumented EVM in go

Question

I'm working on a project where I would like to catch internal transactions and figure out the stack trace. For this reason, I have been trying to define an EVM log collector as recommended here. Unfortunately that answer is 4 years old and EtherQuery library is no longer maintained. My code is the following:

snaps, statedb := MakePreState(rawdb.NewMemoryDatabase(), map[common.Address]core.GenesisAccount{}, true)
preRoot := statedb.IntermediateRoot(false)
defer func() {
    if _, err := snaps.Journal(preRoot); err != nil {
        panic(err)
    }
}()

var tracer *tracers.Tracer
tracer, err := tracers.New("callTracer")
if err != nil { panic(err) }

vmCfg := vm.Config{ Debug: true, Tracer: tracer, NoRecursion: true }
env := vm.NewEVM(vm.Context{BlockNumber: big.NewInt(1)}, statedb, params.TestChainConfig, vmCfg)

contract := vm.NewContract(account{}, account{}, big.NewInt(0), 10000)
contract.Code = []byte{byte(vm.PUSH1), 0x1, byte(vm.PUSH1), 0x1, 0x0}

_, err = env.Interpreter().Run(contract, []byte{}, false)
if err != nil { panic(err) }
fmt.Println(tracer.GetResult())

After running this snippet, I get the following:

[] TypeError: cannot read property 'toString' of undefined    in server-side tracer function 'result'

How should I set up the tracer? Thanks!

How to run instrumented EVM in go

0 Answers0