anchor.diff:      // Fixture setup
       let sut = AutoFoqCustomization()
       // Exercise system and verify outcome
  -    Assert.Throws<ArgumentNullException>(fun () -> 
  -        sut.Customize(null))
  +    raises<ArgumentNullException> <@ sut.Customize(null) @>
       // Teardown
   
   [<Fact>]
  
positive.code:     // Exercise system
      sut.Customize(fixtureStub)
      // Verify outcome
      Assert.Empty(customizations)
      // Teardown
  
  
negative.code:     // Exercise system
      let sut = AutoFoqCustomization()
      // Verify outcome
      verify <@ typeof<ICustomization>.IsAssignableFrom(sut.GetType()) @>
      // Teardown
  
  [<Fact>]
  let InitializeWithNullRelayThrows() =
      // Fixture setup
      // Exercise system and verify outcome
      raises<ArgumentNullException> <@ AutoFoqCustomization(null) @>
      // Teardown
  
  [<Fact>]
  