Fallow for VS Code

Dead code and duplication analyzer for JavaScript/TypeScript projects. Powered by fallow, a Rust-native alternative to knip that is 3-36x faster than knip v5 (2-14x faster than knip v6).

Features

Real-time diagnostics via the fallow LSP server: unused files, exports, types, dependencies, enum/class members, unresolved imports, unlisted deps, and duplicate exports
Quick-fix code actions: remove unused exports, delete unused files
Tree views: browse dead code by issue type and duplicates by clone family in the sidebar
Status bar: see total issue count and duplication percentage at a glance
Auto-fix: remove unused exports and dependencies with one command
Auto-download: the extension downloads the fallow-lsp binary automatically

Installation

From the Marketplace

Search for "Fallow" in the VS Code extensions panel, or install from the command line:

code --install-extension fallow-rs.fallow-vscode

Manual

Install the fallow and fallow-lsp binaries (see fallow installation)
Install the extension VSIX file: code --install-extension fallow-vscode-*.vsix

Commands

Command	Description
`Fallow: Run Analysis`	Run full dead code + duplication analysis and update tree views
`Fallow: Auto-Fix Unused Exports & Dependencies`	Remove unused exports and dependencies
`Fallow: Preview Fixes (Dry Run)`	Show what fixes would be applied without changing files
`Fallow: Restart Language Server`	Restart the fallow-lsp process
`Fallow: Show Output Channel`	Open the Fallow output panel for debugging

Settings

Setting	Default	Description
`fallow.lspPath`	`""`	Path to the `fallow-lsp` binary. Leave empty for auto-detection.
`fallow.autoDownload`	`true`	Automatically download the binary if not found.
`fallow.issueTypes`	all enabled	Toggle individual issue types on/off.
`fallow.duplication.threshold`	`5`	Duplication threshold percentage.
`fallow.duplication.mode`	`"mild"`	Detection mode: `strict`, `mild`, `weak`, or `semantic`.
`fallow.production`	`false`	Production mode: exclude test/dev files, only production scripts.
`fallow.trace.server`	`"off"`	LSP trace level: `off`, `messages`, or `verbose`.

Binary resolution

The extension looks for the fallow-lsp binary in this order:

fallow.lspPath setting (if configured)
fallow-lsp in PATH
Previously downloaded binary in extension storage
Auto-download from GitHub releases (if fallow.autoDownload is enabled)

Development

cd editors/vscode
npm install
npm run build        # Production build
npm run watch        # Watch mode for development
npm run lint         # Type check
npm run package      # Package as .vsix