more tuning

include/ada/url_search_params-inl.h

@@ -233,7 +233,7 @@ inline void url_search_params::sort() {
         return (codePoint1 < codePoint2);
       }
     }
-    return (i < lhs.first.size());
+    return (j < rhs.first.size() || low_surrogate2 != 0);
   });
 }
 

tests/url_search_params.cpp

@@ -268,4 +268,14 @@ TEST(url_search_params, sort_unicode_code_units) {
   ASSERT_EQ(keys.next(), "\xf0\x9f\x8c\x88");
   ASSERT_EQ(keys.next(), "\xef\xac\x83");
   SUCCEED();
+}
+
+TEST(url_search_params, sort_unicode_code_units_edge_case) {
+  ada::url_search_params search_params("\xf0\x9f\x8c\x88\xef\xac\x83&\xf0\x9f\x8c\x88");
+  search_params.sort();
+  ASSERT_EQ(search_params.size(), 2);
+  auto keys = search_params.get_keys();
+  ASSERT_EQ(keys.next(), "\xf0\x9f\x8c\x88");
+  ASSERT_EQ(keys.next(), "\xf0\x9f\x8c\x88\xef\xac\x83");
+  SUCCEED();
 }