eth/tracers: revert reason in call_tracer + error for failed internal calls (#21387)

* tests: add testdata of call tracer

* eth/tracers: return revert reason in call_tracer

* eth/tracers: regenerate assets

* eth/tracers: add error message even if no exec occurrs, fixes #21438

Co-authored-by: Martin Holst Swende <martin@swende.se>

eth/tracers/tracers_test.go

@@ -269,9 +269,31 @@ func TestCallTracer(t *testing.T) {
 				t.Fatalf("failed to unmarshal trace result: %v", err)
 			}
 
-			if !reflect.DeepEqual(ret, test.Result) {
+			if !jsonEqual(ret, test.Result) {
+				// uncomment this for easier debugging
+				//have, _ := json.MarshalIndent(ret, "", " ")
+				//want, _ := json.MarshalIndent(test.Result, "", " ")
+				//t.Fatalf("trace mismatch: \nhave %+v\nwant %+v", string(have), string(want))
 				t.Fatalf("trace mismatch: \nhave %+v\nwant %+v", ret, test.Result)
 			}
 		})
 	}
 }
+
+// jsonEqual is similar to reflect.DeepEqual, but does a 'bounce' via json prior to
+// comparison
+func jsonEqual(x, y interface{}) bool {
+	xTrace := new(callTrace)
+	yTrace := new(callTrace)
+	if xj, err := json.Marshal(x); err == nil {
+		json.Unmarshal(xj, xTrace)
+	} else {
+		return false
+	}
+	if yj, err := json.Marshal(y); err == nil {
+		json.Unmarshal(yj, yTrace)
+	} else {
+		return false
+	}
+	return reflect.DeepEqual(xTrace, yTrace)
+}