public void should_return_true_if_assembly_available()
 {
     var sut = new FileSystem();
     sut.IsAssemblyAvailable("NSubstitute")
         .ShouldBe(true);
 }
 public void should_return_false_if_assembly_not_available()
 {
     var sut = new FileSystem();
     sut.IsAssemblyAvailable("blah")
         .ShouldBe(false);
 }