anchor.diff:  
     @override
     Future<int> delete() async {
  -    if (predicate == null && !canModifyAllInstances) {
  +    var p = predicate;
  +
  +    if (p == null && !canModifyAllInstances) {
         throw new QueryException(QueryExceptionEvent.internalFailure,
             message:
                 "Query would impact all records. This could be a destructive error. Set canModifyAllInstances on the Query to execute anyway.");
  
positive.code:     var buffer = new StringBuffer();
      buffer.write("DELETE FROM ${entity.tableName} ");
  
      if (predicate != null) {
        buffer.write("WHERE ${predicate.format} ");
      }
  
      return context.persistentStore.executeQuery(
          buffer.toString(), predicate?.parameters, timeoutInSeconds,
          returnType: PersistentStoreQueryReturnType.rowCount);
    }
  
  
negative.code:   }
  
    // todo: this sucks
    static List<PropertyToRowMapper> joinElementsFromQueryMatchable(
        QueryMatchableExtension matcherBackedObject) {
      var entity = matcherBackedObject.entity;
      var propertiesToJoin = matcherBackedObject.joinPropertyKeys;
  