c++ - 如何获取gtest TYPED_TEST参数类型

Question

我有一些在 Windows (Visual Studio 2017) 上编写的单元测试，我需要将它们移植到 Linux(GCC 4.9.2 - 我坚持使用这个版本...)。我为我的问题提供了一个简单的例子，它在 Windows 上编译得很好(我认为它不应该编译，因为 MyParamType 是来自 e 模板基类的依赖类型)并且不编译Linux.

例子:

#include <gtest/gtest.h>

template<typename T>
struct MyTest : public testing::Test
{
    using MyParamType = T;
};

using MyTypes = testing::Types<int, float>;
TYPED_TEST_CASE(MyTest, MyTypes);

TYPED_TEST(MyTest, MyTestName)
{
    MyParamType param;
} 

In member function ‘virtual void MyTest_MyTestName_Test::TestBody()’:error: ‘MyParamType’ was not declared in this scope MyParamType param;

通过更改为:

TYPED_TEST(MyTest, MyTestName)
{
    typename MyTest<gtest_TypeParam_>::MyParamType param;
}

代码编译通过了，但是看起来很丑。

有没有简单/好的方法从 TYPED_TEST 获取模板参数类型？

Answer 1

答案隐藏在文档中:

#include <gtest/gtest.h>

template<typename T>
struct MyTest : public testing::Test
{
    using MyParamType = T;
};

using MyTypes = testing::Types<int, float>;
TYPED_TEST_CASE(MyTest, MyTypes);

TYPED_TEST(MyTest, MyTestName)
{
    // To refer to typedefs in the fixture, add the 'typename TestFixture::'
    // prefix.  The 'typename' is required to satisfy the compiler.

    using MyParamType  = typename TestFixture::MyParamType;
}

https://github.com/google/googletest/blob/master/googletest/docs/advanced.md