Add test coverage for concurrent-safe routes and StatusContinue

- Add TestConcurrentAddRouteAndRoutes to test concurrent access to addRoute() and Routes()
- Update TestContextBodyAllowedForStatus to include http.StatusContinue

These tests ensure the new mutex code and constant are covered, fixing codecov coverage drops in PRs #4525 and #4523.

context_test.go

@@ -1031,6 +1031,7 @@ func TestContextGetCookie(t *testing.T) {
 }
 
 func TestContextBodyAllowedForStatus(t *testing.T) {
+	assert.False(t, bodyAllowedForStatus(http.StatusContinue))
 	assert.False(t, bodyAllowedForStatus(http.StatusProcessing))
 	assert.False(t, bodyAllowedForStatus(http.StatusNoContent))
 	assert.False(t, bodyAllowedForStatus(http.StatusNotModified))

gin_test.go

@@ -1067,6 +1067,39 @@ func TestLiteralColonWithHTTPServer(t *testing.T) {
 	assert.Contains(t, w2.Body.String(), "foo")
 }
 
+func TestConcurrentAddRouteAndRoutes(t *testing.T) {
+	router := New()
+
+	done := make(chan bool)
+
+	for i := 0; i < 10; i++ {
+		go func(n int) {
+			router.GET(fmt.Sprintf("/route%d", n), func(c *Context) {
+				c.String(http.StatusOK, fmt.Sprintf("route%d", n))
+			})
+			router.POST(fmt.Sprintf("/route%d", n), func(c *Context) {
+				c.String(http.StatusOK, fmt.Sprintf("route%d", n))
+			})
+			done <- true
+		}(i)
+	}
+
+	for i := 0; i < 10; i++ {
+		go func() {
+			routes := router.Routes()
+			assert.GreaterOrEqual(t, len(routes), 0)
+			done <- true
+		}()
+	}
+
+	for i := 0; i < 20; i++ {
+		<-done
+	}
+
+	routes := router.Routes()
+	assert.Len(t, routes, 20)
+}
+
 // Test that updateRouteTrees is called only once
 func TestUpdateRouteTreesCalledOnce(t *testing.T) {
 	SetMode(TestMode)