public void WithReadConcern_should_return_expected_result() { var originalReadConcern = new ReadConcern(ReadConcernLevel.Linearizable); var subject = new MongoClient().WithReadConcern(originalReadConcern); var newReadConcern = new ReadConcern(ReadConcernLevel.Majority); var result = subject.WithReadConcern(newReadConcern); subject.Settings.ReadConcern.Should().BeSameAs(originalReadConcern); result.Settings.ReadConcern.Should().BeSameAs(newReadConcern); result.WithReadConcern(originalReadConcern).Settings.Should().Be(subject.Settings); }