UTF8/Unicode config filename not supported on Windows

[r2d3]

If I create a config filename with non ascii characters,

./my_app --print > déjà

When I call: ./my_app --config déjà, I got:

my_app-cli.exe --config déjà
déjà was not readable (missing?)
Run with --help for more information.

[r2d3]

I tried using CLI11 version including #875 #878, but this does not solve this issue

[phlptp]

What is the code you are using to parse the arguments?

[r2d3]

Here is the code to reproduce cli11_bug912.tgz

And the command:

# Non accentuated config works
$ cli11_bug --print foo > config
$ cli11_bug -c config
foo

$ cp config déjà
$ cli11_bug -c déjà
déjà was not readable (missing?)
Run with --help for more information.

#include <CLI/CLI.hpp>

#include <iostream>
#include <string>

#ifdef _WIN32
int wmain(int argc, wchar_t* argv[])
#else
int main(int argc, char* argv[])
#endif
{
    std::string filename;
    CLI::App app("cli11_bug");
    app.set_config("-c,--config");
    app.add_flag("--print", "Print configuration and exit")->configurable(false);
    app.add_option("file", filename, "File to process");

    CLI11_PARSE(app);

    if (app.get_option("--print")->as<bool>())
    {
        std::cout << app.config_to_str(true, true);
        return 0;
    }

    std::cout << filename << std::endl;

    return 0;
}

[r2d3]

I am using Git bash to do the cp command with accentuated characters

[bindreams]

So far I was unable to reproduce this, neither on git bash, nor on powershell 5/7, nor on command prompt.

From experience, Unicode on Windows can get corrupted at a number of stages. Could you check a couple of settings for me:

• What terminal are you using? Normal windows terminal is cohost.exe, if you are running in Windows Terminal it's wt.exe, and I believe Git suggests MSYS2-style terminal which is MinTTY.
• Does your Windows installation have this checkmark set:
  
• Can you reproduce this bug if repeating all the steps from PowerShell 7.x instead of Git bash?

[The0Dev]

Hello. I encountered this issue on Windows where configuration files located at (absolute) paths containing Chinese characters failed to be applied. After some investigation, I identified the cause in my case: the from_file function directly passes the filename to ifstream, which fails on Windows because it expects wide strings for Unicode, while the filename is provided as a UTF-8 encoded string. To resolve this, the to_path function should be called before passing the filename to ifstream.

std::ifstream input{to_path(name)};

CLI11/include/CLI/ConfigFwd.hpp

Line 72 in 1df96c8

CLI11_NODISCARD std::vector<ConfigItem> from_file(const std::string &name) const {

To provide a bit more context, I'm using configuration files in the following manner:

//Create a config if it does not exist and return path to its folder as a utf8 encoded string
std::string config_path_global = GetConfigFile("myconf.toml") // may return "C:\Users\张伟\Documents\"

  app.set_config("--conf", "myconf.toml", "Read options from a toml config.")
      ->transform(CLI::FileOnDefaultPath(config_path_global, false))
      ->capture_default_str();