cmd/evm: print vm output when debug flag is on (#16326)

core/vm/logger.go

@@ -45,6 +45,7 @@ type LogConfig struct {
 	DisableMemory  bool // disable memory capture
 	DisableStack   bool // disable stack capture
 	DisableStorage bool // disable storage capture
+	Debug          bool // print output during capture end
 	Limit          int  // maximum length of output, but zero means unlimited
 }
 
@@ -184,6 +185,12 @@ func (l *StructLogger) CaptureFault(env *EVM, pc uint64, op OpCode, gas, cost ui
 func (l *StructLogger) CaptureEnd(output []byte, gasUsed uint64, t time.Duration, err error) error {
 	l.output = output
 	l.err = err
+	if l.cfg.Debug {
+		fmt.Printf("0x%x\n", output)
+		if err != nil {
+			fmt.Printf(" error: %v\n", err)
+		}
+	}
 	return nil
 }