anchor.diff:        }
       }
     },
  -  "index": {
  +  "dest": {
       "index": "dest",
       "routing": "=cat"
     }
  
positive.code:     "index": ["twitter", "blog"],
      "type": ["tweet", "post"]
    },
    "index": {
      "index": "all_together"
    }
  }
  
negative.code:   "source": {
      "index": "source"
    },
    "dest": {
      "index": "dest",
      "pipeline": "some_ingest_pipeline"
    }
  