public void AddOrKeepExtensionWorks() { var pb = new VirtualPathBuilder().CombineWith("~/t.cs"); Assert.IsTrue(pb.GetExtension() == "cs"); pb.AddOrKeepExtension("vb"); Assert.IsTrue(pb.GetExtension() == "cs"); pb.Clear().CombineWith("foo"); Assert.IsFalse(pb.HasExtension()); pb.AddOrKeepExtension("vb"); Assert.IsTrue(pb.GetExtension() == "vb"); }