anchor.diff:  @Test
   @WithMockUser
   public void getMessageWithMockUser() {
  -  String message = messageService.getMessage();
  -  ...
  +String message = messageService.getMessage();
  +...
   }
   ----
   
  
positive.code: [source,java]
  ----
  mvc
      .perform(get("/").with(httpBasic("user","password")))
  ----
  
  will attempt to use HTTP Basic to authenticate a user with the username "user" and the password "password" by ensuring the following header is populated on the HTTP Request:
  
negative.code: [source,java]
  ----
  mvc
  	.perform(get("/").with(authentication(authentication)))
  ----
  
  You can even customize the `SecurityContext` using the following:
  