Fix Mux.Find not correctly handling nested routes (#954)

* Fix Mux.Find not correctly handling nested routes

* Add more test cases for TextMuxFind

* Fix Mux.Find returning partial path for failing cases

Author: joeriddles

mux.go

@@ -378,18 +378,25 @@ func (mx *Mux) Find(rctx *Context, method, path string) string {
 	}
 
 	node, _, _ := mx.tree.FindRoute(rctx, m, path)
+	pattern := rctx.routePattern
+
+	if node != nil {
+		if node.subroutes == nil {
+			e := node.endpoints[m]
+			return e.pattern
+		}
 
-	if node != nil && node.subroutes != nil {
 		rctx.RoutePath = mx.nextRoutePath(rctx)
-		return node.subroutes.Find(rctx, method, rctx.RoutePath)
-	}
+		subPattern := node.subroutes.Find(rctx, method, rctx.RoutePath)
+		if subPattern == "" {
+			return ""
+		}
 
-	if node != nil {
-		e := node.endpoints[m]
-		return e.pattern
+		pattern = strings.TrimSuffix(pattern, "/*")
+		pattern += subPattern
 	}
 
-	return ""
+	return pattern
 }
 
 // NotFoundHandler returns the default Mux 404 responder whenever a route

mux_test.go

@@ -1850,6 +1850,11 @@ func TestMuxFind(t *testing.T) {
 		w.Header().Set("X-Test", "yes")
 		w.Write([]byte("bye"))
 	})
+	r.Route("/yo", func(r Router) {
+		r.Get("/sup", func(w http.ResponseWriter, r *http.Request) {
+			w.Write([]byte("sup"))
+		})
+	})
 	r.Route("/articles", func(r Router) {
 		r.Get("/{id}", func(w http.ResponseWriter, r *http.Request) {
 			id := URLParam(r, "id")
@@ -1868,17 +1873,54 @@ func TestMuxFind(t *testing.T) {
 			w.Write([]byte("user:" + id))
 		})
 	})
+	r.Route("/api", func(r Router) {
+		r.Route("/groups", func(r Router) {
+			r.Route("/v2", func(r Router) {
+				r.Get("/", func(w http.ResponseWriter, r *http.Request) {
+					w.Write([]byte("groups"))
+				})
+				r.Post("/{id}", func(w http.ResponseWriter, r *http.Request) {
+					w.Write([]byte("POST groups"))
+				})
+			})
+		})
+	})
 
 	tctx := NewRouteContext()
 
 	tctx.Reset()
-	if r.Find(tctx, "GET", "/users/1") == "/users/{id}" {
-		t.Fatal("expecting to find match for route:", "GET", "/users/1")
+	if r.Find(tctx, "GET", "") == "/" {
+		t.Fatal("expecting to find pattern / for route: GET")
 	}
 
 	tctx.Reset()
-	if r.Find(tctx, "HEAD", "/articles/10") == "/articles/{id}" {
-		t.Fatal("not expecting to find match for route:", "HEAD", "/articles/10")
+	if r.Find(tctx, "GET", "/nope") != "" {
+		t.Fatal("not expecting to find pattern for route: GET /nope")
+	}
+
+	tctx.Reset()
+	if r.Find(tctx, "GET", "/users/1") != "/users/{id}" {
+		t.Fatal("expecting to find pattern /users/{id} for route: GET /users/1")
+	}
+
+	tctx.Reset()
+	if r.Find(tctx, "HEAD", "/articles/10") != "" {
+		t.Fatal("not expecting to find pattern for route: HEAD /articles/10")
+	}
+
+	tctx.Reset()
+	if r.Find(tctx, "GET", "/yo/sup") != "/yo/sup" {
+		t.Fatal("expecting to find pattern /yo/sup for route: GET /yo/sup")
+	}
+
+	tctx.Reset()
+	if r.Find(tctx, "GET", "/api/groups/v2/") != "/api/groups/v2/" {
+		t.Fatal("expecting to find pattern /api/groups/v2/ for route: GET /api/groups/v2/")
+	}
+
+	tctx.Reset()
+	if r.Find(tctx, "POST", "/api/groups/v2/1") != "/api/groups/v2/{id}" {
+		t.Fatal("expecting to find pattern /api/groups/v2/{id} for route: POST /api/groups/v2/1")
 	}
 }