core/tracing: auto upgrade deprecated hooks

core/state/statedb_hooked.go

@@ -184,8 +184,6 @@ func (s *hookedStateDB) SetNonce(address common.Address, nonce uint64, reason tr
 	s.inner.SetNonce(address, nonce, reason)
 	if s.hooks.OnNonceChangeV2 != nil {
 		s.hooks.OnNonceChangeV2(address, prev, nonce, reason)
-	} else if s.hooks.OnNonceChange != nil {
-		s.hooks.OnNonceChange(address, prev, nonce)
 	}
 }
 

core/state/statedb_hooked_test.go

@@ -98,7 +98,7 @@ func TestHooks(t *testing.T) {
 		OnBalanceChange: func(addr common.Address, prev, new *big.Int, reason tracing.BalanceChangeReason) {
 			emitF("%v.balance: %v->%v (%v)", addr, prev, new, reason)
 		},
-		OnNonceChange: func(addr common.Address, prev, new uint64) {
+		OnNonceChangeV2: func(addr common.Address, prev, new uint64, reason tracing.NonceChangeReason) {
 			emitF("%v.nonce: %v->%v", addr, prev, new)
 		},
 		OnCodeChange: func(addr common.Address, prevCodeHash common.Hash, prevCode []byte, codeHash common.Hash, code []byte) {

core/tracing/hooks.go

@@ -25,6 +25,7 @@
 package tracing
 
 import (
+	"errors"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -33,6 +34,11 @@ import (
 	"github.com/holiman/uint256"
 )
 
+var (
+	// ErrHookConflict is returned when conflicting hooks are exposed.
+	ErrHookConflict = errors.New("hook conflict")
+)
+
 // OpContext provides the context at which the opcode is being
 // executed in, including the memory, stack and various contract-level information.
 type OpContext interface {
@@ -217,6 +223,36 @@ type Hooks struct {
 	OnBlockHashRead BlockHashReadHook
 }
 
+// Upgrade will upgrade the methods to their most recent versions
+// when possible, e.g. use `OnNonceChangeV2` instead of `OnNonceChange`.
+func Upgrade(hooks *Hooks) (*Hooks, error) {
+	if hooks == nil {
+		return &Hooks{}, nil
+	}
+	if hooks.OnNonceChange != nil && hooks.OnNonceChangeV2 != nil {
+		return nil, ErrHookConflict
+	}
+	if hooks.OnSystemCallStart != nil && hooks.OnSystemCallStartV2 != nil {
+		return nil, ErrHookConflict
+	}
+	// Shallow copy
+	tmp := *hooks
+	internal := &tmp
+	if hooks.OnNonceChange != nil {
+		hooks.OnNonceChangeV2 = func(addr common.Address, prev, new uint64, reason NonceChangeReason) {
+			internal.OnNonceChange(addr, prev, new)
+		}
+		hooks.OnNonceChange = nil
+	}
+	if hooks.OnSystemCallStart != nil {
+		hooks.OnSystemCallStartV2 = func(vm *VMContext) {
+			internal.OnSystemCallStart()
+		}
+		hooks.OnSystemCallStart = nil
+	}
+	return hooks, nil
+}
+
 // BalanceChangeReason is used to indicate the reason for a balance change, useful
 // for tracing and reporting.
 type BalanceChangeReason byte

core/tracing/journal.go

@@ -41,12 +41,17 @@ func WrapWithJournal(hooks *Hooks) (*Hooks, error) {
 	if hooks == nil {
 		return nil, fmt.Errorf("wrapping nil tracer")
 	}
-	// No state change to journal, return the wrapped hooks as is
+
-	if hooks.OnBalanceChange == nil && hooks.OnNonceChange == nil && hooks.OnNonceChangeV2 == nil && hooks.OnCodeChange == nil && hooks.OnStorageChange == nil {
+	// Upgrade hooks so we don't have to bother with old versions.
-		return hooks, nil
+	var err error
+	hooks, err = Upgrade(hooks)
+	if err != nil {
+		return nil, err
 	}
-	if hooks.OnNonceChange != nil && hooks.OnNonceChangeV2 != nil {
+
-		return nil, fmt.Errorf("cannot have both OnNonceChange and OnNonceChangeV2")
+	// No state change to journal, return the wrapped hooks as is
+	if hooks.OnBalanceChange == nil && hooks.OnNonceChangeV2 == nil && hooks.OnCodeChange == nil && hooks.OnStorageChange == nil {
+		return hooks, nil
 	}
 
 	// Create a new Hooks instance and copy all hooks
@@ -62,12 +67,10 @@ func WrapWithJournal(hooks *Hooks) (*Hooks, error) {
 	if hooks.OnBalanceChange != nil {
 		wrapped.OnBalanceChange = j.OnBalanceChange
 	}
-	if hooks.OnNonceChange != nil || hooks.OnNonceChangeV2 != nil {
+	if hooks.OnNonceChangeV2 != nil {
 		// Regardless of which hook version is used in the tracer,
 		// the journal will want to capture the nonce change reason.
 		wrapped.OnNonceChangeV2 = j.OnNonceChangeV2
-		// A precaution to ensure EVM doesn't call both hooks.
-		wrapped.OnNonceChange = nil
 	}
 	if hooks.OnCodeChange != nil {
 		wrapped.OnCodeChange = j.OnCodeChange
@@ -156,8 +159,6 @@ func (j *journal) OnNonceChangeV2(addr common.Address, prev, new uint64, reason
 	}
 	if j.hooks.OnNonceChangeV2 != nil {
 		j.hooks.OnNonceChangeV2(addr, prev, new, reason)
-	} else if j.hooks.OnNonceChange != nil {
-		j.hooks.OnNonceChange(addr, prev, new)
 	}
 }
 
@@ -219,8 +220,6 @@ func (b balanceChange) revert(hooks *Hooks) {
 func (n nonceChange) revert(hooks *Hooks) {
 	if hooks.OnNonceChangeV2 != nil {
 		hooks.OnNonceChangeV2(n.addr, n.new, n.prev, NonceChangeRevert)
-	} else if hooks.OnNonceChange != nil {
-		hooks.OnNonceChange(n.addr, n.new, n.prev)
 	}
 }
 

core/tracing/journal_test.go

@@ -297,7 +297,9 @@ func newTracerAllHooks() *tracerAllHooks {
 	for i := 0; i < hooksType.NumField(); i++ {
 		t.hooksCalled[hooksType.Field(i).Name] = false
 	}
+	// Deprecated methods
 	delete(t.hooksCalled, "OnNonceChange")
+	delete(t.hooksCalled, "OnSystemCallStart")
 	return t
 }
 
@@ -322,9 +324,13 @@ func (t *tracerAllHooks) hooks() *Hooks {
 	hooksValue := reflect.ValueOf(h).Elem()
 	for i := 0; i < hooksValue.NumField(); i++ {
 		field := hooksValue.Type().Field(i)
+		// Skip deprecated methods
 		if field.Name == "OnNonceChange" {
 			continue
 		}
+		if field.Name == "OnSystemCallStart" {
+			continue
+		}
 		hookMethod := reflect.MakeFunc(field.Type, func(args []reflect.Value) []reflect.Value {
 			t.hooksCalled[field.Name] = true
 			return nil

eth/tracers/dir.go

@@ -45,6 +45,14 @@ type Tracer struct {
 	Stop func(err error)
 }
 
+func (t *Tracer) upgrade() (*Tracer, error) {
+	upgraded, err := tracing.Upgrade(t.Hooks)
+	if err != nil {
+		return nil, err
+	}
+	return &Tracer{Hooks: upgraded, GetResult: t.GetResult, Stop: t.Stop}, nil
+}
+
 type ctorFn func(*Context, json.RawMessage, *params.ChainConfig) (*Tracer, error)
 type jsCtorFn func(string, *Context, json.RawMessage, *params.ChainConfig) (*Tracer, error)
 
@@ -84,7 +92,11 @@ func (d *directory) New(name string, ctx *Context, cfg json.RawMessage, chainCon
 		cfg = json.RawMessage("{}")
 	}
 	if elem, ok := d.elems[name]; ok {
-		return elem.ctor(ctx, cfg, chainConfig)
+		t, err := elem.ctor(ctx, cfg, chainConfig)
+		if err != nil {
+			return nil, err
+		}
+		return t.upgrade()
 	}
 	// Assume JS code
 	return d.jsEval(name, ctx, cfg, chainConfig)

eth/tracers/live.go

@@ -19,6 +19,7 @@ package tracers
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 
 	"github.com/ethereum/go-ethereum/core/tracing"
 )
@@ -36,6 +37,7 @@ type liveDirectory struct {
 // Register registers a tracer constructor by name.
 func (d *liveDirectory) Register(name string, f ctorFunc) {
 	d.elems[name] = f
+	fmt.Printf("Registered tracer %q\n", name)
 }
 
 // New instantiates a tracer by name.
@@ -44,7 +46,11 @@ func (d *liveDirectory) New(name string, config json.RawMessage) (*tracing.Hooks
 		config = json.RawMessage("{}")
 	}
 	if f, ok := d.elems[name]; ok {
-		return f(config)
+		hooks, err := f(config)
+		if err != nil {
+			return nil, err
+		}
+		return tracing.Upgrade(hooks)
 	}
 	return nil, errors.New("not found")
 }

eth/tracers/live/supply.go

@@ -120,6 +120,7 @@ func newSupplyTracer(cfg json.RawMessage) (*tracing.Hooks, error) {
 		OnGenesisBlock:   t.onGenesisBlock,
 		OnTxStart:        t.onTxStart,
 		OnBalanceChange:  t.onBalanceChange,
+		OnNonceChange:    t.onNonceChange,
 		OnEnter:          t.onEnter,
 		OnExit:           t.onExit,
 		OnClose:          t.onClose,
@@ -326,3 +327,6 @@ func (s *supplyTracer) write(data any) {
 		log.Warn("failed to write to supply tracer log file", "error", err)
 	}
 }
+func (t *supplyTracer) onNonceChange(addr common.Address, prev, new uint64) {
+	fmt.Printf("Nonce change for %s: %d -> %d\n", addr, prev, new)
+}