anchor.diff:  Future testDbCommandCreation() {
     Db db = new Db('${DefaultUri}mongo_dart-test');
     return db.open().then((d) {
  -    DbCommand dbCommand = new DbCommand(db, "student", 0, 0, 1, {}, {});
  +    DbCommand dbCommand = new DbCommand(
  +        db,
  +        "student",
  +        0,
  +        0,
  +        1,
  +        {},
  +        {});
       expect('mongo_dart-test.student', dbCommand.collectionNameBson.value);
       db.close();
     });
  
positive.code: }
  
  main() {
  //  hierarchicalLoggingEnabled = true;
  //  Logger.root.level = Level.OFF;
  //  new Logger('Db').level = Level.ALL;
  //  var listener = (LogRecord r) {
  //    var name = r.loggerName;
  //    if (name.length > 15) {
  //      name = name.substring(0, 15);
  //    }
  //    while (name.length < 15) {
  //      name = "$name ";
  //    }
  //    print("${r.time}: $name: ${r.message}");
  //  };
  //  Logger.root.onRecord.listen(listener);
  //
  
    group('DbCollection tests:', () {
      test('testAuthComponents', testAuthComponents);
    });
    group('DBCommand:', () {
      test('testAuthentication', testAuthentication);
      test('testAuthenticationWithUri', testAuthenticationWithUri);
      test('testDropDatabase', testDropDatabase);
  
negative.code:   });
  }
  
  Future testGetNonce() async {
    var result = await db.getNonce();
    expect(result["ok"], 1);
  }
  
  Future getBuildInfo() async {
    var result = await db.getBuildInfo();
    expect(result["ok"], 1);
  }
  
  Future testIsMaster() async {
    var result = await db.isMaster();
    expect(result["ok"], 1);
  }
  
  testCollectionCreation() {
  