add test for duplicate dynamic segent name

actix-router/src/resource.rs

@@ -1770,6 +1770,12 @@ mod tests {
         match_methods_agree!(["/v{v}", "/ver/{v}"] => "", "s/v", "/v1", "/v1/xx", "/ver/i3/5", "/ver/1");
     }
 
+    #[test]
+    #[should_panic]
+    fn duplicate_segment_name() {
+        ResourceDef::new("/user/{id}/post/{id}");
+    }
+
     #[test]
     #[should_panic]
     fn invalid_dynamic_segment_delimiter() {