Edit: As it turns out, the issue I originally had was expected behavior, but it would be better if mappings like this would be rejected when someone tries to set them, so I'm leaving the original issue text below:

I'm trying to specify a field like this in 2.1.0:

...
"city": {
    "type": "completion",
    "preserve_separators": false,
    "payloads": true,
    "fields": {
        "analyzed": {
            "type": "completion",
            "analyzer": "standard",
            "payloads": true,
        }
    }
}
...

Indexing seems to be okay, but when searching, I get an error saying that "Field [city.analyzed] is not a completion suggest field". Am I wrong to expect this to work?