Stale Buffer Guard

Stale Buffer Guard warns when the active VS Code editor has unsaved local changes and the file on disk changed after the editor's saved baseline.

It is designed for the specific footgun where another process edits a file while you still have unsaved edits in the same editor.

Behavior

• Records each file editor's disk last-modified time when the document opens, saves, is cleanly refreshed by VS Code, or you explicitly refresh the baseline.
• Clean buffers are allowed to track disk automatically.
• Watches for disk changes and periodically checks the active editor.
• If the editor is dirty and the file on disk is newer than the stored editor baseline, shows:
  • a warning status bar item: STALE EDITOR BUFFER
  • a warning diagnostic on the first line
  • a warning background across the visible editor buffer
• editor-title actions in the always-visible editor header:
  • Check Active Editor
  • Discard Buffer and Reload
  • Keep Buffer
  • Hide Warning
• Clicking the status bar item opens an action picker. It does not reload the file unless you choose Discard Buffer and Reload.
• The extension never silently reloads editors.
• Discard Buffer and Reload always asks for explicit confirmation, even when the editor is clean.
• Keep Buffer accepts the current disk version as the new baseline and keeps your editor contents.
• Hide Warning hides the warning background and editor-title actions for the current stale snapshot only. The buffer remains stale until you reload, save, keep the buffer, or the disk file changes again.

Commands

• Stale Buffer Guard: Check Active Editor
• Stale Buffer Guard: Keep Editor Buffer
• Stale Buffer Guard: Discard Buffer and Reload
• Stale Buffer Guard: Hide Editor Warning
• Stale Buffer Guard: Show Actions
• Stale Buffer Guard: Explain Stale Warning

Settings

{
  "staleBufferGuard.enabled": true,
  "staleBufferGuard.pollIntervalMs": 2000
}

Try It Locally

Open this directory in VS Code:

code ~/dev/stalebufferguard

Press F5 to launch an Extension Development Host.

In the Extension Development Host:

1. Open a file.
2. Edit the same file from another terminal or tool.
3. Return to the editor. The buffer should show a warning background and editor-title actions.

Install Locally

For quick development usage, run an Extension Development Host with this folder.

For a normal install, package it with vsce:

npm install -g @vscode/vsce
vsce package
code --install-extension stale-buffer-guard-0.0.1.vsix