Devtools symlinks broken when BAR is installed via Flatpak

[NortySpock]

Issue:

When BAR is installed via Flatpak (info.beyondallreason.bar), the Spring engine runs sandboxed. Symlinks created by just link::create bar point into $DEVTOOLS_DIR/Beyond-All-Reason (typically somewhere under the user's home directory), but the Flatpak sandbox denies the engine access to follow the symlink outside its permitted filesystem.

Steps to reproduce:

1. Install BAR via Flatpak.
2. Clone BAR-Devtools and clone/link the BAR repo:

   cd /home/you/BAR-Devtools
   just repos::clone bar
   just link::create bar
   

3. Launch BAR (via Flatpak desktop entry or flatpak run).
4. Check logs — the engine prints:

   Warning: [FSA::GetFileModificationTime] error 'No such file or directory' getting last modification time of file '/home/you/.var/app/info.beyondallreason.bar/data/games/Beyond-All-Reason.sdd'
   Warning: [IsPathOnSpinningDisk] Error 'No such file or directory' getting stat() for file '/home/you/.var/app/info.beyondallreason.bar/data/games/Beyond-All-Reason.sdd'
   

Root cause:

The symlink itself is valid:

~/.var/app/info.beyondallreason.bar/data/games/Beyond-All-Reason.sdd
  → /home/you/BAR-Devtools/Beyond-All-Reason

But the Flatpak runtime's filesystem sandbox blocks the engine from reading paths outside /home/you/.var/app/info.beyondallreason.bar/ (and a handful of other permitted locations). The kernel returns ENOENT to the engine when it tries to stat() the symlink target, even though the path exists outside the sandbox.

Workaround:

Manually grant the BAR Flatpak access to the devtools directory:

flatpak override --user info.beyondallreason.bar --filesystem=/home/you/BAR-Devtools

Replace the path with wherever your DEVTOOLS_DIR lives.

Proposed fix:

detect_game_dir() in scripts/setup.sh currently checks ~/.local/state/Beyond All Reason and WSL-specific paths, but does not detect the Flatpak data directory at ~/.var/app/info.beyondallreason.bar/data. A fix could either:

1. Teach detect_game_dir() to recognize the Flatpak path (and emit a warning if flatpak override hasn't granted access to the devtools source).
2. Add a just doctor check that detects Flatpak installations and advises the user to run flatpak override if their devtools source is outside the Flatpak sandbox.
3. Future: have just link::create detect the Flatpak runtime and suggest the flatpak override command automatically, or alternatively copy/sync the repo into the Flatpak-visible games directory instead of symlinking.

Additional context:

• detect_game_dir() source: scripts/setup.sh lines 1661-1695 — no Flatpak path handling.
• The intended dev workflow is just bar::launch (native), which avoids this entirely. The issue only affects users who launch BAR via the Flatpak entrypoint while using Devtools symlinks for development.
• dev.Containerfile doesn't reference Flatpak; this is purely a host-side sandbox constraint.

LLM Disclosure

Diagnosed and researched by DeepSeek v4 Flash. Reviewed prior to submission by NortySpock.

[NortySpock]

Detection and doctor recommendation of a manual fix is now working thanks to PR #48 , next step would be automatically handling flatpak permissions in setup