Desktop integration and URI scheme registration don't work on linux

[gudvinr]

Description of the bug

If you use either of "Desktop integration" or "Allow downloads from printables.com", application can't do that and emits an error:
Performing desktop integration failed because the application directory was not found.

After reading source, I found this:

    for (size_t i = 0; i < target_candidates.size(); ++i)
    {
        if (contains_path_dir(target_candidates[i], "applications")) {
            // if all failed - try creating default home folder
            if (i == target_candidates.size() - 1) {
                // create $HOME/.local/share
                // create_desktop_file(path, desktop_file)
            }
        }
    }

    if(target_dir_desktop.empty()) {
        show_error(nullptr, _L("Performing desktop integration failed because the application directory was not found."));
        return;
    }

So, only place where desktop file created is inside loop which constructed from environment variables:

std::vector<std::string>target_candidates;
resolve_path_from_var("XDG_DATA_HOME", target_candidates);
resolve_path_from_var("XDG_DATA_DIRS", target_candidates);

There's even comment saying:

// If $XDG_DATA_HOME is either not set or empty, a default equal to $HOME/.local/share should be used. 
// If $XDG_DATA_DIRS is either not set or empty, a value equal to /usr/local/share/:/usr/share/ should be used. 

In my case (and probably in most cases too) these variables are empty, this loop won't even be started. At least that's what I see from quick skimming through the code.
I believe that this condition should happen after this loop in case if no folder was found or $HOME/.local/share could be added to this array, so if any of explicitly defined paths were not found, it simply won't be used.
Default XDG_DATA_DIRS can be skipped whatsoever because those paths usually aren't accessible by users anyway and XDG_DATA_HOME takes precedence.

I run pre-built binary, not appimage.

Project file & How to reproduce

1. Open PrusaSlicer 2.6.0 alpha2 or alpha3
2. Use "Desktop integration"

Checklist of files included above

• Project file
• Screenshot

Version of PrusaSlicer

2.6.0-alpha3+linux-x64-GTK3

Operating system

I use arch btw

Printer model

Artillery Genius Pro

[kocikdav]

Hello, thank you for reporting. You were right in describing the problem. It should be fixed by commit 4c51023 and available in next alpha.