Function TestRequestPatternInMiddleware

http/mux_test.go:200–251

TestRequestPatternInMiddleware verifies that r.Pattern is set by the built-in middleware before user-registered middlewares run. This is critical for observability middleware (e.g., otelhttp) that reads r.Pattern to set the http.route span attribute at span-start time.

(t *testing.T)

// critical for observability middleware (e.g., otelhttp) that reads
// r.Pattern to set the http.route span attribute at span-start time.
func TestRequestPatternInMiddleware(t *testing.T) {
	cases := []struct {
		Name     string
		Method   string
		Pattern  string
		URL      string
		Expected string
	}{
		{
			Name:     "simple",
			Method:   "GET",
			Pattern:  "/users",
			URL:      "/users",
			Expected: "GET /users",
		},
		{
			Name:     "with segment",
			Method:   "POST",
			Pattern:  "/users/{id}",
			URL:      "/users/123",
			Expected: "POST /users/{id}",
		},
		{
			Name:     "with wildcard",
			Method:   "GET",
			Pattern:  "/files/{*path}",
			URL:      "/files/a/b/c",
			Expected: "GET /files/{*path}",
		},
	}

	for _, c := range cases {
		t.Run(c.Name, func(t *testing.T) {
			var middlewareCalled bool
			mux := NewMuxer()
			// Register a user middleware that reads r.Pattern —
			// simulating otelhttp.NewMiddleware.
			mux.Use(func(next http.Handler) http.Handler {
				return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
					assert.Equal(t, c.Expected, r.Pattern)
					middlewareCalled = true
					next.ServeHTTP(w, r)
				})
			})
			mux.Handle(c.Method, c.Pattern, func(_ http.ResponseWriter, _ *http.Request) {})
			req, _ := http.NewRequest(c.Method, c.URL, nil)
			w := httptest.NewRecorder()
			mux.ServeHTTP(w, req)
			assert.True(t, middlewareCalled)
		})
	}
}

func TestResolvePattern(t *testing.T) {
	cases := []struct {