bugfix(filesystem): Fix existing files being reported as missing after they are created again

[tintinhamans]

Creating a file that the existence cache already knows about marks it as missing. doesFileExist then says no for it until the game is closed, even though the file is on disk.

FileInstance is an UnsignedByte, so ~FileInstance(0) is the int -1. The unset instanceDoesNotExist of 255 never equals that, so it gets incremented anyway and wraps to 0.

I ran into this while reloading game data in one process. The map preview gets copied to MapPreviews a second time and then draws as the missing texture.

On main the map transfer can run into it. ConnectionManager::processFile asks if the file exists and then creates it, so receiving a file you already have marks it as missing. GameLogic::loadMapINI then skips that map's map.ini, solo.ini and map.str.

[coderabbitai]

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📥 Commits

Reviewing files that changed from the base of the PR and between f746af7 and 0e1e242.

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📒 Files selected for processing (1)

• Core/GameEngine/Source/Common/System/FileSystem.cpp

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Walkthrough

The file-existence cache’s maximum-value check now casts the complemented FileInstance value back to FileInstance before comparison.

Changes

File-existence cache

Layer / File(s)	Summary
Update sentinel comparison Core/GameEngine/Source/Common/System/FileSystem.cpp	The sentinel comparison casts the complemented FileInstance value back to FileInstance.

Priority: ➖ Normal

Estimated code review effort: 1 (Trivial) | ~5 minutes

Change: Bug fix

Suggested reviewers: bobtista

Merge Risk: ⚪ Minimal · up to 0e1e2

The cache now preserves the missing-file sentinel when an existing file is recreated, avoiding the reported false-missing result. No actionable merge-blocking risk remains.

Pre-merge checks | 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description check		The description clearly explains the filesystem cache bug, its cause, and the affected workflows. It directly relates to the changeset.
Title check		The title clearly and concisely identifies the filesystem bug: existing files are reported as missing after they are created again.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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[greptile-apps]

Confidence Score: 5/5

[Medium impact] This PR appears safe to merge; the cast fixes the missing-file marker comparison.

Summary

Fixes the file-existence cache when an existing file is created again.

• Opening a known file no longer marks it as missing.

_{Reviews (1) · Last reviewed commit: "bugfix(filesystem): Fix existing files b..." · Reviewed by Greptile}

[xezon]

I will put a block on this because I also have a big pending filesystem change coming up which also touches many things here.