Backup not restored if multiple mods overwrite game files

[paoloambrosio]

Uninstalling Thunderflash mods removes some game files. Example: when 03-GT3_Custom_AI_Drivers_2.41.zip and 05-FIA_GT1_Custom_AI_Drivers_v1.5.zip are installed together, UserData\CustomAIDrivers\README.txt is deleted on uninstall.

To reproduce:

• Create a file UserData\foo.txt in the game directory
• Create a fake mod with only UserData\foo.txt inside
• Duplicate the mod
• Install/uninstall the two mods will remove the file

Explanation:

• On install, UserData\foo.txt.orig is created with a backup of UserData\foo.txt
• On uninstall, the first mod restores UserData\foo.txt from UserData\foo.txt.orig, the second mod deletes UserData\foo.txt because no orig file exists

Fix:

• I think the only way to fix it is not to add the file to the state in the first place when it was overwritten by another mod.