package mergo import ( "reflect" "testing" "time" ) type transformer struct { } func (s *transformer) Transformer(t reflect.Type) func(dst, src reflect.Value) error { return nil } func Test_deepMergeTransformerInvalidDestination(t *testing.T) { foo := time.Time{} src := reflect.ValueOf(foo) deepMerge(reflect.Value{}, src, make(map[uintptr]*visit), 0, &Config{ Transformers: &transformer{}, }) // this test is intentionally not asserting on anything, it's sole // purpose to verify deepMerge doesn't panic when a transformer is // passed and the destination is invalid. }