Go Mod Size Viewer

A Visual Studio Code extension that displays the disk size of Go module dependencies in go.mod files.

Features

• 📦 Package Size Display: View the disk size of each dependency
• 🎯 Two Display Modes:
  • Hover Mode: Shows size when you hover over a package (default)
  • Inlay Mode: Displays sizes inline as hints
• ⚡ Smart Caching: Caches results to avoid repeated calculations
• 🎨 Customizable: Configure display units and cache duration
• 🚀 Lightweight: Runs independently without affecting gopls performance

Usage

Hover Mode (Default)

Simply hover over any require line in your go.mod file:

require (
    github.com/gin-gonic/gin v1.9.1     // Hover to see size
    github.com/pkg/errors v0.9.1        // Hover to see size
)

You'll see a popup showing:

• Package name and version
• Total size
• Number of files
• Local path

Inlay Hints Mode

Enable inlay hints in settings to see sizes inline:

require (
    github.com/gin-gonic/gin v1.9.1  // 2.3 MB
    github.com/pkg/errors v0.9.1     // 156 KB
)

Configuration

Open VS Code settings and search for "Go Mod Size Viewer":

{
    // Enable/disable the extension
    "gomodSizeViewer.enabled": true,
    
    // Display mode: "hover" or "inlay"
    "gomodSizeViewer.displayMode": "hover",
    
    // Cache duration in seconds (default: 1 hour)
    "gomodSizeViewer.cacheDuration": 3600,
    
    // Size unit: "auto", "KB", "MB", or "GB"
    "gomodSizeViewer.unit": "auto"
}

Commands

• Go Mod Size Viewer: Clear Cache - Clear all cached size data
• Go Mod Size Viewer: Refresh - Recalculate sizes for current file

Access commands via Command Palette (Cmd/Ctrl + Shift + P)

Requirements

• Visual Studio Code 1.80.0 or higher
• Go modules must be downloaded to $GOPATH/pkg/mod
• For Unix/Linux/Mac: Works best with du and find commands available

How It Works

1. Parses require statements in go.mod
2. Locates packages in $GOPATH/pkg/mod directory
3. Calculates directory size using:
   • Native du command on Unix/Linux/Mac (fast)
   • Recursive file traversal on Windows (cross-platform)
4. Caches results to improve performance

Performance Notes

• First calculation for each package may take a few seconds
• Results are cached for the configured duration (default: 1 hour)
• Calculations run asynchronously without blocking the editor
• Independent from gopls - doesn't affect Go language features

Limitations

• Only shows sizes for already downloaded packages
• Requires packages to exist in $GOPATH/pkg/mod
• May be slower on network file systems
• Windows: Uses recursive traversal (slower than Unix du command)

Troubleshooting

Size not showing?

• Ensure the package is downloaded: go mod download
• Check that $GOPATH is set correctly
• Verify the package exists in $GOPATH/pkg/mod

Slow performance?

• Increase cache duration in settings
• Switch to hover mode if using inlay mode
• Clear cache if it becomes stale

Contributing

Issues and pull requests are welcome on GitHub.

License

MIT License - see LICENSE file for details

Credits

Inspired by the feature request: golang/vscode-go#3667