Minimal testing

minitest.cpp

// clang++ -o minitest minitest.cpp -std=c++1y -stdlib=libc++

#include <iostream>

#define TEST_PREDICATE(expr, oper)                                   \
    do {                                                             \
        auto expr__ = (expr);                                        \
        if (!(expr__ oper)) {                                        \
            std::cout << __FILE__ << ":" << __LINE__ << " "          \
                      << "FAILED " << #expr << " " << #oper          \
                      << " (actual: " << expr__ << ")" << std::endl; \
        }                                                            \
    } while (0)

#define TEST_TRUE(expr)                                     \
    do {                                                    \
        if (!(expr)) {                                      \
            std::cout << __FILE__ << ":" << __LINE__ << " " \
                      << "FAILED " #expr << std::endl;      \
        }                                                   \
    } while (0)

#define TEST_MACRO(_1, _2, NAME, ...) NAME

#define TEST(...) TEST_MACRO(__VA_ARGS__, TEST_PREDICATE, TEST_TRUE)(__VA_ARGS__)

// Test target sample

template <typename item_t>
class rectangle
{
private:
    item_t width_;
    item_t height_;
public:
    rectangle(item_t width, item_t height)
        : width_(width), height_(height)
    {
    }

    item_t area() const
    {
        return width_ + height_; // TODO: Fix bug here
    }

    bool is_square() const
    {
        return width_ == height_;
    }

};

// Test sample

int main()
{
    rectangle<int> r(2, 3);
    TEST(r.area(), == 6);
    TEST(r.area(), >= 6);
    TEST(r.area(), != 5);
    TEST(r.is_square()); // TODO: Fix bug here
    return 0;
}

$ ./minitest 
minitest.cpp:58 FAILED r.area() == 6 (actual: 5)
minitest.cpp:59 FAILED r.area() >= 6 (actual: 5)
minitest.cpp:60 FAILED r.area() != 5 (actual: 5)
minitest.cpp:61 FAILED r.is_square()