Mocking IndicesNamespace?

How do I mock IElasticClient.Indices, in other words, the IndicesNamespace?

Can we instead have it so that IElasticClient.Indices refers to an interface (for instance IIndicesNamespace instead)?

Right now, I can’t mock indices using NSubstitute:

var fakeIndicesNamespace = Substitute.For<IndicesNamespace>(); //crashes with message: System.NotSupportedException : Parent does not have a default constructor. The default constructor must be explicitly defined.

var fakeElasticClient = Substitute.For<IElasticClient>();
fakeElasticClient.Indices.Returns(fakeIndicesNamespace);

[ffMathy]

Why make it so hard? Why can’t we just turn IndicesNamespace into an interface? That way, everyone can mock like they are used to in virtually every single other NuGet package out there, using their own mocking framework?

[mkorman-cat]

I have some concerns with the suggestions raised in #4076

• Essentially, by asking your users to create their own wrappers, you’re aking them to do the job that you didn’t want to do, which is introduce the interfaces and mockability. You’re ignoring some genuine use cases and pushing the complexity to the users
• I don’t want to turn my unit tests into integration tests. I just want to mock a specific response to ensure that my code does the right thing when I get a certain response from the library

At the end of the day, use of interfaces and mockability is considered good practices. It would be amazing if your library accepted those. Thanks!