Fixes route overloading for dynamic routes

Addresses #353, now dynamic routes work alongside our newly minted
overloaded routes! Also fixed an unintended side effect where methods
were still being passed in as None for `Sanic.add_route`.

sanic/router.py

@@ -210,29 +210,40 @@ class Router:
         url = host + url
         # Check against known static routes
         route = self.routes_static.get(url)
+        method_not_supported = InvalidUsage(
+            'Method {} not allowed for URL {}'.format(
+                method, url), status_code=405)
         if route:
+            if route.methods and method not in route.methods:
+                raise method_not_supported
             match = route.pattern.match(url)
         else:
+            route_found = False
             # Move on to testing all regex routes
             for route in self.routes_dynamic[url_hash(url)]:
                 match = route.pattern.match(url)
-                if match:
+                route_found |= match is not None
+                # Do early method checking
+                if match and method in route.methods:
                     break
             else:
                 # Lastly, check against all regex routes that cannot be hashed
                 for route in self.routes_always_check:
                     match = route.pattern.match(url)
-                    if match:
+                    route_found |= match is not None
+                    # Do early method checking
+                    if match and method in route.methods:
                         break
                 else:
+                    # Route was found but the methods didn't match
+                    if route_found:
+                        raise method_not_supported
                     raise NotFound('Requested URL {} not found'.format(url))
 
-        if route.methods and method not in route.methods:
-            raise InvalidUsage(
-                'Method {} not allowed for URL {}'.format(
-                    method, url), status_code=405)
-
         kwargs = {p.name: p.cast(value)
                   for value, p
                   in zip(match.groups(1), route.parameters)}
-        return route.handler, [], kwargs
+        route_handler = route.handler
+        if hasattr(route_handler, 'handlers'):
+            route_handler = route_handler.handlers[method]
+        return route_handler, [], kwargs

sanic/sanic.py

@@ -90,7 +90,7 @@ class Sanic:
     def patch(self, uri, host=None):
         return self.route(uri, methods=["PATCH"], host=host)
 
-    def add_route(self, handler, uri, methods=None, host=None):
+    def add_route(self, handler, uri, methods=frozenset({'GET'}), host=None):
         """
         A helper method to register class instance or
         functions as a handler to the application url