MapDelegate overrides default routing when calling with Html.ActionLink

[Buildstarted]

Given the following routes

routes.MapDelegate("RouteFailureTest", "home/test",
context => new HomeController().HomeTest(context.HttpContext));

routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional }//, // Parameter defaults
);

a call to @Html.ActionLink("Log Off", "Logout", "User") always matches the "RouteFailureTest".

My guess is that it's related to the lack of default controller/action values so the ActionLink, providing the default values matches the delegate route.

It's fairly simple to reproduce, use a standard MVC3 application (with default Home/Account controllers) add the MapDelegate route above and check the Login/Home/About Us links. They will always match the RouteFailureTest route.

routes.MapRoute(
"ShouldntMatch", // Route name
"home/test", // URL with parameters
null // Parameter defaults
);

Confirmed it's the null defaults. This route produces the same results as the MapDelegate by matching any Html.ActionLink or other similar helpers

[haacked]

This is an issue with the underlying ASP.NET Routing. Read http://haacked.com/archive/2010/11/21/named-routes-to-the-rescue.aspx for more details.

We could in theory fix it by having MapDelegate return a route that checks to see if the URL pattern has any parameters (aka sections with {curlybraces}) and if it doesn't, the route doesn't implement GetVirtualPath. That's the method that generates a URL. What that would mean is such an URL cannot be used for URL generation.

Seem reasonable?

[Buildstarted]

Interesting. It makes sense now that I read that. However since a lot of people use the default RouteLink/ActionLink and their ilk without specifying a named routes I'm pretty sure it's reasonable to handle it in the way you specify.