Function null_field_value

nodedb-query/src/msgpack_scan/group_key.rs:155–159

()

    #[test]
    fn null_field_value() {
        let doc = encode(&json!({"v": null}));
        let key = build_group_key(&doc, &["v".into()]);
        assert_eq!(key, "[null]");
    }

    #[test]
    fn float_field() {