router: support Routes accepting multiple strings as method

handler.go

@@ -5,6 +5,7 @@
 package flamego
 
 import (
+	"fmt"
 	"net/http"
 	"reflect"
 
@@ -52,7 +53,7 @@ func (invoke teapotInvoker) Invoke([]interface{}) ([]reflect.Value, error) {
 // gain up to 3x performance improvement.
 func validateAndWrapHandler(h Handler, wrapper func(Handler) Handler) Handler {
 	if reflect.TypeOf(h).Kind() != reflect.Func {
-		panic("handler must be a callable function")
+		panic(fmt.Sprintf("handler must be a callable function, but got %T", h))
 	}
 
 	if inject.IsFastInvoker(h) {

router.go

@@ -50,10 +50,12 @@ type Router interface {
 	Trace(routePath string, handlers ...Handler) *Route
 	// Any is a shortcut for `r.Route("*", routePath, handlers)`.
 	Any(routePath string, handlers ...Handler) *Route
-	// Routes is a shortcut of adding same handlers for different HTTP methods.
+	// Routes is a shortcut of adding route with same list of handlers for different
+	// HTTP methods.
 	//
 	// Example:
-	//	f.Routes("/", "GET,POST", handlers)
+	//  f.Routes("/", http.MethodGet, http.MethodPost, handlers...)
+	//  f.Routes("/", "GET,POST", handlers...)
 	Routes(routePath, methods string, handlers ...Handler) *Route
 	// NotFound configures a http.HandlerFunc to be called when no matching route is
 	// found. When it is not set, http.NotFound is used. Be sure to set
@@ -272,9 +274,24 @@ func (r *router) Routes(routePath, methods string, handlers ...Handler) *Route {
 		panic("empty methods")
 	}
 
-	var route *Route
+	var ms []string
 	for _, m := range strings.Split(methods, ",") {
-		route = r.Route(strings.TrimSpace(m), routePath, handlers)
+		ms = append(ms, strings.TrimSpace(m))
+	}
+
+	// Collect methods from handlers if they are strings
+	for i, h := range handlers {
+		m, ok := h.(string)
+		if !ok {
+			handlers = handlers[i:]
+			break
+		}
+		ms = append(ms, m)
+	}
+
+	var route *Route
+	for _, m := range ms {
+		route = r.Route(m, routePath, handlers)
 	}
 	return route
 }

router_test.go

@@ -119,29 +119,52 @@ func TestRouter_Route(t *testing.T) {
 
 func TestRouter_Routes(t *testing.T) {
 	ctx := newMockContext()
-	contextCreator := func(w http.ResponseWriter, r *http.Request, params route.Params, handlers []Handler, urlPath urlPather) internalContext {
+	contextCreator := func(_ http.ResponseWriter, _ *http.Request, params route.Params, _ []Handler, _ urlPather) internalContext {
 		ctx.MockContext.ParamFunc.SetDefaultHook(func(s string) string {
 			return params[s]
 		})
 		return ctx
 	}
-	r := newRouter(contextCreator)
 
-	r.Routes("/routes", "GET,POST", func() {})
+	t.Run("use single string", func(t *testing.T) {
+		r := newRouter(contextCreator)
 
-	for _, m := range []string{http.MethodGet, http.MethodPost} {
-		gotRoute := ""
-		ctx.run_ = func() { gotRoute = ctx.Param("route") }
+		r.Routes("/routes", "GET,POST", func() {})
 
-		resp := httptest.NewRecorder()
-		req, err := http.NewRequest(m, "/routes", nil)
-		assert.Nil(t, err)
+		for _, m := range []string{http.MethodGet, http.MethodPost} {
+			gotRoute := ""
+			ctx.run_ = func() { gotRoute = ctx.Param("route") }
 
-		r.ServeHTTP(resp, req)
+			resp := httptest.NewRecorder()
+			req, err := http.NewRequest(m, "/routes", nil)
+			assert.Nil(t, err)
 
-		assert.Equal(t, http.StatusOK, resp.Code)
-		assert.Equal(t, "/routes", gotRoute)
-	}
+			r.ServeHTTP(resp, req)
+
+			assert.Equal(t, http.StatusOK, resp.Code)
+			assert.Equal(t, "/routes", gotRoute)
+		}
+	})
+
+	t.Run("use multiple strings", func(t *testing.T) {
+		r := newRouter(contextCreator)
+
+		r.Routes("/routes", http.MethodGet, http.MethodPost, func() {})
+
+		for _, m := range []string{http.MethodGet, http.MethodPost} {
+			gotRoute := ""
+			ctx.run_ = func() { gotRoute = ctx.Param("route") }
+
+			resp := httptest.NewRecorder()
+			req, err := http.NewRequest(m, "/routes", nil)
+			assert.Nil(t, err)
+
+			r.ServeHTTP(resp, req)
+
+			assert.Equal(t, http.StatusOK, resp.Code)
+			assert.Equal(t, "/routes", gotRoute)
+		}
+	})
 }
 
 func TestRouter_AutoHead(t *testing.T) {