title: Strategy to make a third-party library implement interfaces?
body: <p>I would like to write unit tests for some of my classes. Some of my classes depend on a third-party library which uses the file system and has no interfaces to mock.</p>
  
  <p>I'd to mock the class to avoid its dependencies on the filesystem, since my code is really only concerned about the results of that code.</p>
  
  <p>What is the best strategy to use to mock the concrete classes of the library without modifying the initial library?</p>
  
  <p>I'm thinking I might create a wrapper object that implements an interface and contains the initial library's object. However, I want to make sure there's not maybe a better way before I start down this path.</p>
  
  <p>Or, Would a tool like TypeMock be better suited than Moq in this case?</p>