void ContainerTest::output() {
    std::stringstream out;

    std::vector<int> a{1, 9, 3, 4};
    std::vector<int> b{1, 2, 3, 4};

    {
        Error e(&out);
        Comparator<Compare::Container<std::vector<int>>> compare;
        CORRADE_VERIFY(!compare(a, b));
        compare.printErrorMessage(e, "a", "b");
    }

    CORRADE_COMPARE(out.str(), "Containers a and b have different contents. Actual 9 but 2 expected on position 1.\n");
}
void ContainerTest::outputExpectedSmaller() {
    std::stringstream out;

    std::vector<int> a{1, 2, 3, 4};
    std::vector<int> b{1, 2, 3};

    {
        Error e(&out);
        Comparator<Compare::Container<std::vector<int>>> compare;
        CORRADE_VERIFY(!compare(a, b));
        compare.printErrorMessage(e, "a", "b");
    }

    CORRADE_COMPARE(out.str(), "Containers a and b have different size, actual 4 but 3 expected. Actual has 4 on position 3.\n");
}