Fallow - Codebase Health

Version updated for https://github.com/fallow-rs/fallow to version v2.14.1.

  • This action is used across all versions by 3 repositories.

Action Type

This is a Composite action.

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Action Summary

This GitHub Action, Fallow, is a codebase analysis tool designed for TypeScript and JavaScript projects. It automates the detection of unused code, duplicate code, code complexity, architectural issues, and dependency problems, enabling developers to identify inefficiencies and maintain cleaner, more maintainable codebases. Built with Rust for high performance, it requires no configuration, supports real-time re-analysis, and integrates seamlessly with popular frameworks and monorepos.

What’s Changed

HTML Entry File Parsing

Fallow now parses HTML files and follows referenced JS/CSS assets, fixing false-positive dead-code reports in Vite, Parcel, and similar HTML-first bundler setups.

What’s new

  • <script src="..."> tags (both type="module" and classic) create graph edges to referenced JS/TS files
  • <link rel="stylesheet" href="..."> creates edges to referenced CSS files
  • <link rel="modulepreload" href="..."> creates edges to preloaded modules
  • Remote URLs (http://, https://, //, data:) are automatically skipped
  • HTML comments are stripped before matching (no false edges from commented-out tags)
  • HTML files are exempt from unused-file detection (nothing imports HTML, so “unused” is meaningless)

Effect

Given a Vite-style project:

<!-- index.html -->
<link rel="stylesheet" href="./src/global.css" />
<script type="module" src="./src/entry.ts"></script>

Previously, entry.ts, global.css, and all their transitive imports would be falsely reported as dead code. Now they are correctly marked as reachable through the HTML entry point.

Also in this release

  • Parcel index.html entry pattern – the Parcel plugin now auto-detects index.html as a runtime entry point
  • Coverage gaps inline suppression – // fallow-ignore-next-line coverage-gaps now works

Full Changelog: https://github.com/fallow-rs/fallow/compare/v2.14.0...v2.14.1