windows260.cpp

#include <iostream>
#include <fstream>
#include <filesystem>

int main()
{
    const auto sandbox = std::filesystem::absolute(std::filesystem::path{ "sandbox" });

    if (std::filesystem::exists(sandbox))
    {
        std::clog << "Removing " << sandbox << " because it exists" << std::endl;
        std::filesystem::remove_all(sandbox);
    }
    std::filesystem::create_directories(sandbox);

    std::clog << "Sandbox lenght: " << sandbox.string().size() << std::endl;

    // Other constants from here are not handled, it should prove the point, if you have a lot till the limit
    const auto toTheLimit = 260 - sandbox.string().size();
    const auto problematic = toTheLimit * 2 / 3;
    const auto longName = std::string(problematic, 'b');

    const auto levelX = sandbox / "dPCRRelease-windows_amd64-v11.1.0.68-51da8cf-mimic" ;
    const auto branchA = sandbox / "a" / longName;
    const auto branchB = sandbox / "pa" / ("p" + longName);

    std::filesystem::create_directories(branchA);
    std::filesystem::create_directories(branchB);
    std::filesystem::current_path(branchA);
    std::clog << "Changed dir" << std::endl;

    {
        std::ofstream ofs{ branchB / "t" };
        ofs << "welp" << std::endl;
    }

    const std::string input = "../../pa/p" + longName;
    const auto inputRelative = input;
    const auto inputAbsolute = std::filesystem::absolute(inputRelative);
    const auto inputProcessed = std::filesystem::relative(inputAbsolute);

    std::clog << "inputRelative: " << std::filesystem::exists(inputRelative) << " -- " << inputRelative << std::endl;
    std::clog << "inputAbsolute: " << std::filesystem::exists(inputAbsolute) << " -- " << inputAbsolute << std::endl;
    std::clog << "inputProcessed: " << std::filesystem::exists(inputProcessed) << " -- " << inputProcessed << std::endl;
}