GTest-针对不同类型的参数化测试

时间:2019-05-13 15:47:01

标签: c++ googletest gmock

我想将参数化测试与类型化测试混合使用。这是我的尝试:

struct X {};

struct Y {};

template <typename T>
struct MyTestFixture: public ::testing::Test
{
    T t;
};

template <typename T, typename Param>
struct MyTestFixtureWithParam : public MyTestFixture<T>, 
                                public ::testing::WithParamInterface<Param>
{
};

using MyTestFixtureWithXandString = MyTestFixtureWithParam<X, std::string>;

TEST_P(MyTestFixtureWithXandString, Test1)
{
}

INSTANTIATE_TEST_CASE_P(Name, MyTestFixtureWithXandString, 
                        ::testing::Values("a", "b"));

using MyTestFixtureWithYandString = MyTestFixtureWithParam<Y, std::string>;

TEST_P(MyTestFixtureWithYandString, Test1)
{

}

INSTANTIATE_TEST_CASE_P(Name, MyTestFixtureWithYandString, 
                        ::testing::Values("a", "b"));

Gtest是否包含一些混合了TYPED_TEST和TEST_P的宏,或者上述代码是实现我的目标的唯一方法?

1 个答案:

答案 0 :(得分:1)

据我所知可能没有这样的宏,但是有如下一种可能的方法。


基本思路

让我们定义以下结构abCase。 这里的a::strb::str是我们要测试的参数:

// types
struct X {};
struct Y {};

// "parameters"
struct a { static constexpr char str[] = "a"; };
struct b { static constexpr char str[] = "b"; };

template<class T, class P>
struct Case
{
    using type = T;

    static std::string GetParam()
    {
        return P::str;
    }
};

在单个测试逻辑中测试类型XY的所有组合以及字符串参数的基本思想是使用此结构Case来指定测试类型和参数,如下所示:

using TestTypes = ::testing::Types<Case<X, a>, Case<X, b>, Case<Y, a>, Case<Y, b>>;

template <class T>
class MyTestFixture: public ::testing::Test {};

TYPED_TEST_CASE(MyTestFixture, TestTypes);

TYPED_TEST(MyTestFixture, Test12) 
{
    // X or Y
    TypeParam::type t;

    // "a" or "b"
    const std::string str = TypeParam::GetParam();
}

改进

现在我们的问题是如何改善类型和字符串参数的所有组合的构造。 我已经回答了almost same problem。 在当前情况下,所有可能的{X, Y}{a, b}对都由一维整数0,1,2,3标记,如下所示:

0 -> (0/2, 0%2) = (0,0) -> Case<X, a>
1 -> (1/2, 1%2) = (0,1) -> Case<X, b>
2 -> (2/2, 2%2) = (1,0) -> Case<Y, a>
3 -> (3/2, 3%2) = (1,1) -> Case<Y, b>

其中2{a, b}的大小。 编写函数的方法很简单,如下所示可以使用此算法进行所有可能的组合。 例如,Combinations_t<std::tuple<X, Y>, a, b>等于std::tuple<Case<X,a>, Case<X,b>, Case<Y,a>, Case<Y,b>>的类型:

Live DEMO

template<class TupleType, class TupleParam, std::size_t I>
struct make_case
{
    static constexpr std::size_t N = std::tuple_size<TupleParam>::value;

    using type = Case<typename std::tuple_element<I / N, TupleType >::type,
                      typename std::tuple_element<I % N, TupleParam>::type>;
};

template <class T1, class T2, class Is>
struct make_combinations;

template <class TupleType, class TupleParam, std::size_t... Is>
struct make_combinations<TupleType, TupleParam, std::index_sequence<Is...>>
{
    using tuples = std::tuple<typename make_case<TupleType, TupleParam, Is>::type...>;
};

template<class TupleTypes, class... Params>
using Combinations_t = typename make_combinations
                       <TupleTypes,
                        std::tuple<Params...>,
                        std::make_index_sequence<(std::tuple_size<TupleTypes>::value)*(sizeof...(Params))>>
                     ::tuples;

应用此post的答案,我们可以将此元组Combinations_t<...>划分为类型列表,这里我应用Nawaz的简单类型。 然后,最后,可以按以下步骤进行所有测试:

template <class T>
class MyTestFixture : public ::testing::Test {};

template<class T>
struct Test;

template<class ...T>
struct Test<std::tuple<T...>>
{
    using Types = ::testing::Types<T...>;
};

using TestTypes = Test<Combinations_t<std::tuple<X, Y>, a, b>>::Types;

TYPED_TEST_CASE(MyTestFixture, TestTypes);

TYPED_TEST(MyTestFixture, Test12)
{
    // X or Y
    TypeParam::type t;

    // "a" or "b"
    const std::string str = TypeParam::GetParam();
}