IgnoreLens

Highlights how many files each ignore line matches and flags those hitting zero for easy identification.

Features

• Match Counts: Shows the number of matched files after each pattern in italics, colour-coded to match the line.
• Line Decorations: Redundant patterns (that don't match any files) are highlighted in red.
• Real-time Updates: Decorations update automatically when you edit the file or when files are added/removed from the workspace.

How It Works

View flow diagram

IgnoreLens works with any file that uses VS Code's ignore language type. It analyses each line and checks whether the pattern matches any files in your current workspace:

• Red: The pattern doesn't match any files (redundant)
• No decoration: Patterns that match files, comments, and blank lines

Usage

1. Open any file with the ignore language type in VS Code
2. Patterns will automatically be decorated based on whether they match files

To use IgnoreLens with any file, change its language mode to ignore by clicking the language indicator in the status bar (bottom-right) or using the command palette (Ctrl+Shift+P → "Change Language Mode").

Configuration

Decoration Styles

• none - No visual decoration
• background - Coloured background on the line
• text - Coloured text (default)
• both - Both background and text colour

Match Count Display

IgnoreLens tracks a cumulative set where patterns add files and negations remove them. Implements Git-like directory traversal where negations cannot un-ignore files under ignored directories.

Example output:

node_modules/    +444        (444)
*.js             +1    ≡22   (445)
!src/            −0    ∅1  ✗10   (444)

Customising Colours

You can customise the colours in your settings.json:

{
  "workbench.colorCustomizations": {
    "ignorelens.noMatchForeground": "#f14c4c",
    "ignorelens.noMatchBackground": "#4a1a1a40",
    "ignorelens.matchCountForeground": "#6A9955",
    "ignorelens.negationForeground": "#CCAA00"
  }
}

Colours use hex format: #RRGGBB or #RRGGBBAA (with alpha for transparency). For example, #4a1a1a40 is dark red at 25% opacity.

Supported Patterns

IgnoreLens supports standard ignore file pattern syntax:

• * - Matches anything except path separators
• ** - Matches any path including separators
• ? - Matches any single character
• ! - Negation patterns
• / - Directory anchoring
• # - Comments

Troubleshooting

If match counts aren't showing, settings are missing, or the extension behaves unexpectedly, try uninstalling and reinstalling. VS Code can sometimes get into a state where an updated extension doesn't fully load. A clean reinstall usually fixes it.

Limitations

Empty directories are not detected. Directories are discovered by scanning files, so patterns targeting empty directories (e.g., empty-folder/) will always show zero matches even if the directory exists.

Acknowledgements

This project was developed with assistance from:

• Claude Code (Opus 4.5)
• OpenAI Codex (GPT-5.1-Codex-Max)

Thanks to GitSparTV for identifying the cumulative set tracking issue.

Licence

MIT License - Copyright (c) 2025 Jason Gordon

Free to use, modify, and distribute. See LICENSE for details.