Function BlockWorkers

src/test/threadpool_tests.cpp:67–78

Block a number of worker threads by submitting tasks that wait on `release_sem`. Returns the futures of the blocking tasks, ensuring all have started and are waiting.

// Block a number of worker threads by submitting tasks that wait on `release_sem`.
// Returns the futures of the blocking tasks, ensuring all have started and are waiting.
std::vector<std::future<void>> BlockWorkers(ThreadPool& threadPool, std::counting_semaphore<>& release_sem, size_t num_of_threads_to_block)
{
    assert(threadPool.WorkersCount() >= num_of_threads_to_block);
    std::latch ready{static_cast<std::ptrdiff_t>(num_of_threads_to_block)};
    std::vector<std::future<void>> blocking_tasks(num_of_threads_to_block);
    for (auto& f : blocking_tasks) f = Submit(threadPool, [&] {
        ready.count_down();
        release_sem.acquire();
    });
    ready.wait();
    return blocking_tasks;
}

// Test 0, submit task to a non-started, interrupted, or stopped pool
BOOST_AUTO_TEST_CASE(submit_fails_with_correct_error)