Add support for manually invoking the NoRoute handler (#59)

* feat(router): add HandleNoRoute method

* feat: simple semantic update for ErrNotSupported.

---------

Co-authored-by: tigerwill90 <contact@sylvainmuller.ch>

Author: tigerwill90

fox.go

@@ -99,6 +99,7 @@ const (
 // Router is a lightweight high performance HTTP request router that support mutation on its routing tree
 // while handling request concurrently.
 type Router struct {
+	noRouteBase            HandlerFunc
 	noRoute                HandlerFunc
 	noMethod               HandlerFunc
 	tsrRedirect            HandlerFunc
@@ -138,7 +139,7 @@ var _ http.Handler = (*Router)(nil)
 func New(opts ...GlobalOption) (*Router, error) {
 	r := new(Router)
 
-	r.noRoute = DefaultNotFoundHandler
+	r.noRouteBase = DefaultNotFoundHandler
 	r.noMethod = DefaultMethodNotAllowedHandler
 	r.autoOptions = DefaultOptionsHandler
 	r.clientip = noClientIPResolver{}
@@ -151,7 +152,7 @@ func New(opts ...GlobalOption) (*Router, error) {
 		}
 	}
 
-	r.noRoute = applyMiddleware(NoRouteHandler, r.mws, r.noRoute)
+	r.noRoute = applyMiddleware(NoRouteHandler, r.mws, r.noRouteBase)
 	r.noMethod = applyMiddleware(NoMethodHandler, r.mws, r.noMethod)
 	r.tsrRedirect = applyMiddleware(RedirectHandler, r.mws, defaultRedirectTrailingSlashHandler)
 	r.autoOptions = applyMiddleware(OptionsHandler, r.mws, r.autoOptions)
@@ -361,6 +362,11 @@ func (fox *Router) NewRoute(pattern string, handler HandlerFunc, opts ...RouteOp
 	return rte, nil
 }
 
+// HandleNoRoute calls the no route handler with the provided [Context].
+func (fox *Router) HandleNoRoute(c Context) {
+	fox.noRouteBase(c)
+}
+
 // Len returns the number of registered route.
 func (fox *Router) Len() int {
 	tree := fox.getRoot()

fox_test.go

@@ -4806,6 +4806,29 @@ func TestRouterWithAllowedMethod(t *testing.T) {
 	}
 }
 
+func TestRouterHandleNoRoute(t *testing.T) {
+	called := 0
+	m := MiddlewareFunc(func(next HandlerFunc) HandlerFunc {
+		return func(c Context) {
+			called++
+			next(c)
+		}
+	})
+
+	f, err := New(WithMiddleware(m))
+	require.NoError(t, err)
+	require.NoError(t, onlyError(f.Handle(http.MethodGet, "/foo", func(c Context) {
+		c.Fox().HandleNoRoute(c)
+	})))
+
+	w := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/foo", nil)
+	f.ServeHTTP(w, req)
+	assert.Equal(t, http.StatusNotFound, w.Code)
+	assert.Equal(t, 1, called)
+
+}
+
 func TestRouterWithAllowedMethodAndIgnoreTsEnable(t *testing.T) {
 	f, _ := New(WithNoMethod(true), WithIgnoreTrailingSlash(true))
 

options.go

@@ -57,7 +57,7 @@ func WithNoRouteHandler(handler HandlerFunc) GlobalOption {
 		if handler == nil {
 			return fmt.Errorf("%w: no route handler cannot be nil", ErrInvalidConfig)
 		}
-		s.router.noRoute = handler
+		s.router.noRouteBase = handler
 		return nil
 	})
 }

response_writer.go

@@ -328,9 +328,7 @@ func relevantCaller() runtime.Frame {
 	return frame
 }
 
-var errHttpNotSupported = fmt.Errorf("%w", http.ErrNotSupported)
-
 // ErrNotSupported returns an error that Is http.ErrNotSupported, but is not == to it.
 func ErrNotSupported() error {
-	return errHttpNotSupported
+	return fmt.Errorf("%w", http.ErrNotSupported)
 }