anchor.diff:      s.AssemblyName.Data |> should be (equal ^ Some "Test")
   
   [<Test>]
  -let ``parse - add new file``() =
  +let ``ProjectSystem - parse - add new file``() =
       let pf = FsProject.parse astInput
       let f = {SourceFile.Include = "Test.fsi"; Condition = None; OnBuild = BuildAction.Compile; Link = None; Copy = None}
       let pf' = FsProject.addSourceFile "/" f pf
  
positive.code:     files |> Seq.length |> should be (equal 3)
  
  [<Test>]
  let ``parse - add reference``() =
      let pf = FsProject.parse astInput
      let r = {Reference.Empty with Include = "System.Xml"}
      let pf' = FsProject.addReference r pf
      pf'.References |> Seq.length |> should be (equal 6)
  
  [<Test>]
  let ``parse - add existing reference``() =
      let pf = FsProject.parse astInput
      let r = {Reference.Empty with Include = "System"}
      let pf' = FsProject.addReference r pf
      pf'.References |> Seq.length |> should be (equal 5)
  
  [<Test>]
  let ``parse - remove reference``() =
      let pf = FsProject.parse astInput
      let r = {Reference.Empty with Include = "System"}
      let pf' = FsProject.removeReference r pf
      pf'.References |> Seq.length |> should be (equal 4)
  
  [<Test>]
  let ``parse - remove not existing reference``() =
      let pf = FsProject.parse astInput
      let r = {Reference.Empty with Include = "System.Xml"}
      let pf' = FsProject.removeReference r pf
      pf'.References |> Seq.length |> should be (equal 5)
  
  [<Test>]
  let ``parse - move up``() =
      let pf = FsProject.parse astInput
      let pf' = FsProject.moveUp "App.config" pf
      let files = pf'.SourceFiles.AllFiles()
  
negative.code:     |> should equal false
  
  [<Test>]
  let ``ProjectSystem - parse - move down``() =
      let pf = FsProject.parse astInput
      let pf' = FsProject.moveDown "app.config" pf
      let files = pf'.SourceFiles.AllFiles()
  