如何使用googletest通过引用参数传递来测试void函数？

Question

This is the function that I have.

int square(const int value)
{
    return value * value;
}

void square2(const int value, int& output)
{
    output = value * value;
}

I can test square without problem. But how do I test square2?

This is how I currently test.

TEST(SquareTests, Square)
{
    EXPECT_EQ(0, square(0));
    EXPECT_EQ(4, square(-2));
}

TEST(SquareTests, SquareParameter)
{
    //EXPECT_EQ(0, square2(0));
    //EXPECT_EQ(4, square2(-2));
}

Answer 1

TEST(SquareTests, SquareParameterRef)
{
    int result = -1;
    square2(0, result);
    EXPECT_EQ(0, result);

    square2(-2, result);
    EXPECT_EQ(4, result);
}