@Test public void tag_customizer_withContext() {

  when(parseValue.apply(input, context)).thenReturn("value");
  tag.tag(input, context, customizer);
  verify(parseValue).apply(input, context);
  verifyNoMoreInteractions(parseValue); // doesn't parse twice
  verify(customizer).tag("key", "value");
  verifyNoMoreInteractions(customizer); // doesn't tag twice
}