anchor.diff:  
   
   [<Test>]
  -let ``parse - AST gets all project files`` () =
  +let ``ProjectSystem - parse - AST gets all project files`` () =
       let projectFile = FsProject.parse astInput
       System.Diagnostics.Debug.WriteLine projectFile
       projectFile.SourceFiles.AllFiles() |> Seq.length |> should be (equal 3)
   
   [<Test>]
  -let ``parse - AST gets all references`` () =
  +let ``ProjectSystem - parse - AST gets all references`` () =
       let projectFile = FsProject.parse astInput
       projectFile.References |> Seq.length|> should be (equal 5)
   
   [<Test>]
  -let ``parse - AST gets correct settings`` () =
  +let ``ProjectSystem - parse - AST gets correct settings`` () =
       let projectFile = FsProject.parse astInput
       let s = projectFile.Settings
       s.Configuration.Data |> should be (equal ^ Some "Debug")
  
positive.code:     |> should equal "app.config"
  
  [<Test>]
  let ``parse - move down nonexistent files ``() =
      let pf = FsProject.parse astInput
      let pf' = FsProject.moveDown "dont_exist.fs" pf
      pf'.SourceFiles.AllFiles()
  
negative.code: 
  // TODO: complete test code
  [<Test>]
  let ``ProjectSystem - parse - add above (?)``() =
      true |> should equal true
  
  // TODO: complete test code
  [<Test>]
  let ``ProjectSystem - parse - add below (?)``() =
      true |> should equal true
  
  [<Test>]
  let ``ProjectSystem - parse - remove dir``() =
      let pf = FsProject.parse projectWithDirs
      let pf' = FsProject.removeDirectory "OneDirectory" pf
      let files = pf'.SourceFiles.AllFiles()
  