public void RegisterSerializer_RegisterSpecificSerializer_RegisteredSuccessfully() { // Arrange var mongoDatabaseBuilder = new MongoDatabaseBuilder(_mongoOptions); var arrangedSerializer = new SimpleStringRegisteredSerializer(); mongoDatabaseBuilder.RegisterSerializer <SimpleString>(arrangedSerializer); // Act mongoDatabaseBuilder.Build(); // Assert IBsonSerializer <SimpleString> registeredSerializer = BsonSerializer.LookupSerializer <SimpleString>(); Assert.True(registeredSerializer is SimpleStringRegisteredSerializer); }