ResponseEmpty error handling

fetch.go

@@ -164,7 +164,7 @@ func Request[T any](url string, config ...Config) (T, *Error) {
 	var t T
 	typeOf := reflect.TypeOf(t)
 
-	if typeOf != nil && typeOf == typeFor[ResponseEmpty]() {
+	if typeOf != nil && typeOf == typeFor[ResponseEmpty]() && firstDigit(res.StatusCode) == 2 {
 		re := any(&t).(*ResponseEmpty)
 		re.Status = res.StatusCode
 		re.DuplicateHeaders = res.Header

fetch_test.go

@@ -109,6 +109,11 @@ func TestRequest_ResponseEmpty(t *testing.T) {
 	if res.Headers()["Content-type"] != "application/json" {
 		t.Errorf("wrong headers")
 	}
+
+	_, err = Request[ResponseEmpty]("400.error")
+	if err == nil || err.Unwrap().Error() != "Bad Request" {
+		t.Errorf("Even with ResponseEmpty error should read the body")
+	}
 }
 
 func TestPostString(t *testing.T) {

mock.go

@@ -38,6 +38,8 @@ func mockDNS(url string, req *http.Request) *mockResponse {
 		return &mockResponse{Status: 200, Body: `[1, 2, 3]`}
 	case "my.ip":
 		return &mockResponse{Status: 200, Headers: map[string][]string{"Content-type": {"text/plain"}}, Body: `8.8.8.8`}
+	case "400.error":
+		return &mockResponse{Status: 400, Body: `Bad Request`}
 	case "echo.me":
 		body, err := io.ReadAll(req.Body)
 		if err != nil {