string ToString() const { return strings::StrCat(first, "->", second); }
};

class CApiFunctionTest : public ::testing::Test {
 protected:
  CApiFunctionTest()
      : s_(TF_NewStatus()),
        func_graph_(TF_NewGraph()),
        host_graph_(TF_NewGraph()),
        func_(nullptr) {}

  void SetUp() override {}

  ~CApiFunctionTest() override {
    TF_DeleteFunction(func_);
    TF_DeleteGraph(host_graph_);