anchor.diff:  
   Future testCompoundQuery() async {
     for (var n = 0; n < 10; n++) {
  -    collection.insert({"my_field": n, "str_field": "str_$n"});
  +    await collection.insert({"my_field": n, "str_field": "str_$n"});
     }
     var result = await collection
         .find(where.gt("my_field", 8).or(where.lt('my_field', 2)))
  
positive.code: Future testSimpleQuery() async {
    ObjectId id;
    for (var n = 0; n < 10; n++) {
      collection.insert({"my_field": n, "str_field": "str_$n"});
    }
  
    var result = await collection.find(where.gt("my_field", 5).sortBy('my_field'))
  
negative.code: 
  Future testCount() async {
    for (int n = 0; n < 167; n++) {
      await collection.insert({"a": n});
    }
    var result = await collection.count();
    expect(result, 167);
  }
  
  Future testDistinct() async {
    await collection.insert({"foo": 1});
    await collection.insert({"foo": 2});
    await collection.insert({"foo": 2});
    await collection.insert({"foo": 3});
    await collection.insert({"foo": 3});
    await collection.insert({"foo": 3});
    var result = await collection.distinct("foo");
  
    List values = result['values'];
  