code: @Test public void enableSerializationFeature() throws Exception {
    this.context.register(JacksonAutoConfiguration.class);
    EnvironmentTestUtils.addEnvironment(this.context,"spring.jackson.serialization.indent_output:true");
    this.context.refresh();
    ObjectMapper mapper=this.context.getBean(ObjectMapper.class);
    assertFalse(SerializationFeature.INDENT_OUTPUT.enabledByDefault());
    assertTrue(mapper.getSerializationConfig().hasSerializationFeatures(SerializationFeature.INDENT_OUTPUT.getMask()));
  }
  