move noopT to native

eth/tracers/js/goja.go

@@ -94,8 +94,6 @@ func fromBuf(vm *goja.Runtime, bufType goja.Value, buf goja.Value, allowString b
 // jsTracer is an implementation of the Tracer interface which evaluates
 // JS functions on the relevant EVM hooks. It uses Goja as its JS engine.
 type jsTracer struct {
-	tracers.NoopTracer
-
 	vm                *goja.Runtime
 	env               *tracing.VMContext
 	toBig             toBigFn               // Converts a hex string into a JS bigint

eth/tracers/native/4byte.go

@@ -50,7 +50,6 @@ func init() {
 //	  0xc281d19e-0: 1
 //	}
 type fourByteTracer struct {
-	tracers.NoopTracer
 	ids               map[string]int      // ids aggregates the 4byte ids found
 	interrupt         uint32              // Atomic flag to signal execution interruption
 	reason            error               // Textual reason for the interruption

eth/tracers/native/call.go

@@ -106,7 +106,6 @@ type callFrameMarshaling struct {
 }
 
 type callTracer struct {
-	tracers.NoopTracer
 	callstack []callFrame
 	config    callTracerConfig
 	gasLimit  uint64

eth/tracers/noop.go → eth/tracers/native/noop.go

@@ -14,7 +14,7 @@
 // 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 tracers
+package native
 
 import (
 	"encoding/json"
@@ -25,6 +25,7 @@ import (
 
 	"github.com/ledgerwatch/erigon/core/tracing"
 	"github.com/ledgerwatch/erigon/core/types"
+	"github.com/ledgerwatch/erigon/eth/tracers"
 )
 
 func init() {
@@ -36,9 +37,9 @@ func init() {
 type NoopTracer struct{}
 
 // newNoopTracer returns a new noop tracer.
-func newNoopTracer(ctx *Context, _ json.RawMessage) (*Tracer, error) {
+func newNoopTracer(ctx *tracers.Context, _ json.RawMessage) (*tracers.Tracer, error) {
 	t := &NoopTracer{}
-	return &Tracer{
+	return &tracers.Tracer{
 		Hooks: &tracing.Hooks{
 			OnTxStart:       t.OnTxStart,
 			OnTxEnd:         t.OnTxEnd,

eth/tracers/util_test.go

@@ -0,0 +1,59 @@
+// Copyright 2023 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 tracers
+
+import (
+	"testing"
+
+	"github.com/ledgerwatch/erigon/core/vm"
+)
+
+func TestMemCopying(t *testing.T) {
+	for i, tc := range []struct {
+		memsize  int64
+		offset   int64
+		size     int64
+		wantErr  string
+		wantSize int
+	}{
+		{0, 0, 100, "", 100},    // Should pad up to 100
+		{0, 100, 0, "", 0},      // No need to pad (0 size)
+		{100, 50, 100, "", 100}, // Should pad 100-150
+		{100, 50, 5, "", 5},     // Wanted range fully within memory
+		{100, -50, 0, "offset or size must not be negative", 0},                        // Error
+		{0, 1, 1024*1024 + 1, "reached limit for padding memory slice: 1048578", 0},    // Error
+		{10, 0, 1024*1024 + 100, "reached limit for padding memory slice: 1048666", 0}, // Error
+	} {
+		mem := vm.NewMemory()
+		mem.Resize(uint64(tc.memsize))
+		cpy, err := GetMemoryCopyPadded(mem.Data(), tc.offset, tc.size)
+		if want := tc.wantErr; want != "" {
+			if err == nil {
+				t.Fatalf("test %d: want '%v' have no error", i, want)
+			}
+			if have := err.Error(); want != have {
+				t.Fatalf("test %d: want '%v' have '%v'", i, want, have)
+			}
+			continue
+		}
+		if err != nil {
+			t.Fatalf("test %d: unexpected error: %v", i, err)
+		}
+		if want, have := tc.wantSize, len(cpy); have != want {
+			t.Fatalf("test %d: want %v have %v", i, want, have)
+		}
+	}
+}