From 76e7406a5cd84dd9c45dbdbff2aa23b1c308e839 Mon Sep 17 00:00:00 2001
From: stoorx <me@stoorx.one>
Date: Mon, 24 Feb 2025 14:26:21 +0300
Subject: [PATCH] Refactor `Combine()` generator function

---
 googletest/include/gtest/gtest-param-test.h   |  9 ++++---
 .../include/gtest/internal/gtest-param-util.h | 26 +++++--------------
 2 files changed, 12 insertions(+), 23 deletions(-)

diff --git a/googletest/include/gtest/gtest-param-test.h b/googletest/include/gtest/gtest-param-test.h
index e305e715..f5caed68 100644
--- a/googletest/include/gtest/gtest-param-test.h
+++ b/googletest/include/gtest/gtest-param-test.h
@@ -404,9 +404,12 @@ inline internal::ParamGenerator<bool> Bool() { return Values(false, true); }
 // INSTANTIATE_TEST_SUITE_P(TwoBoolSequence, FlagDependentTest,
 //                          Combine(Bool(), Bool()));
 //
-template <typename... Generator>
-internal::CartesianProductHolder<Generator...> Combine(const Generator&... g) {
-  return internal::CartesianProductHolder<Generator...>(g...);
+template <typename... T>
+internal::ParamGenerator<std::tuple<T...>> Combine(
+    internal::ParamGenerator<T>&&... generators) {
+  return internal::ParamGenerator<std::tuple<T...>>(
+      new internal::CartesianProductGenerator<std::tuple<T...>, T...>(
+          std::forward<decltype(generators)>(generators)...));
 }
 
 // ConvertGenerator() wraps a parameter generator in order to cast each produced
diff --git a/googletest/include/gtest/internal/gtest-param-util.h b/googletest/include/gtest/internal/gtest-param-util.h
index 01e3e9e1..b2bdf16d 100644
--- a/googletest/include/gtest/internal/gtest-param-util.h
+++ b/googletest/include/gtest/internal/gtest-param-util.h
@@ -807,14 +807,14 @@ internal::ParamGenerator<typename Container::value_type> ValuesIn(
 
 namespace internal {
 
-template <typename... T>
-class CartesianProductGenerator
-    : public ParamGeneratorInterface<::std::tuple<T...>> {
+template <typename R, typename... T>
+class CartesianProductGenerator : public ParamGeneratorInterface<R> {
  public:
-  typedef ::std::tuple<T...> ParamType;
+  using ParamType = R;
+
+  explicit CartesianProductGenerator(ParamGenerator<T>&&... g)
+      : generators_(std::forward<decltype(g)>(g)...) {}
 
-  CartesianProductGenerator(const std::tuple<ParamGenerator<T>...>& g)
-      : generators_(g) {}
   ~CartesianProductGenerator() override = default;
 
   ParamIteratorInterface<ParamType>* Begin() const override {
@@ -924,20 +924,6 @@ class CartesianProductGenerator
   std::tuple<ParamGenerator<T>...> generators_;
 };
 
-template <class... Gen>
-class CartesianProductHolder {
- public:
-  CartesianProductHolder(const Gen&... g) : generators_(g...) {}
-  template <typename... T>
-  operator ParamGenerator<::std::tuple<T...>>() const {
-    return ParamGenerator<::std::tuple<T...>>(
-        new CartesianProductGenerator<T...>(generators_));
-  }
-
- private:
-  std::tuple<Gen...> generators_;
-};
-
 template <typename From, typename To, typename Func>
 class ParamGeneratorConverter : public ParamGeneratorInterface<To> {
  public: