add console.log/error support

eth/tracers/js/goja.go

@@ -21,7 +21,9 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
+	"os"
 	"slices"
+	"strings"
 	"sync"
 
 	"github.com/dop251/goja"
@@ -470,7 +472,26 @@ func wrapError(context string, err error) error {
 // It depends on type converters having been set up.
 func (t *jsTracer) setBuiltinFunctions() {
 	vm := t.vm
-	// TODO: load console from goja-nodejs
+	// Initialize console object with log and error methods
+	console := vm.NewObject()
+	console.Set("log", func(call goja.FunctionCall) goja.Value {
+		var output []string
+		for _, argument := range call.Arguments {
+			output = append(output, fmt.Sprintf("%v", argument))
+		}
+		fmt.Fprintln(os.Stdout, strings.Join(output, " "))
+		return goja.Undefined()
+	})
+	console.Set("error", func(call goja.FunctionCall) goja.Value {
+		var output []string
+		for _, argument := range call.Arguments {
+			output = append(output, fmt.Sprintf("%v", argument))
+		}
+		fmt.Fprintln(os.Stderr, strings.Join(output, " "))
+		return goja.Undefined()
+	})
+	vm.Set("console", console)
+
 	vm.Set("toHex", func(v goja.Value) string {
 		b, err := t.fromBuf(vm, v, false)
 		if err != nil {

eth/tracers/js/tracer_test.go

@@ -146,6 +146,16 @@ func TestTracer(t *testing.T) {
 		}, { // tests ctx.coinbase
 			code: "{lengths: [], step: function(log) { }, fault: function() {}, result: function(ctx) { var coinbase = ctx.coinbase; return toAddress(coinbase); }}",
 			want: `{"0":0,"1":0,"2":0,"3":0,"4":0,"5":0,"6":0,"7":0,"8":0,"9":0,"10":0,"11":0,"12":0,"13":0,"14":0,"15":0,"16":0,"17":0,"18":0,"19":0}`,
+		}, {
+			code: `{
+				step: function() {
+					console.log("test log");
+					console.error("test error");
+				},
+				fault: function() {},
+				result: function() {},
+			}`,
+			want: `{}`,
 		},
 	} {
 		if have, err := execTracer(tt.code, tt.contract); tt.want != string(have) || tt.fail != err {