php-cleanup

PHP/WordPress Dead Code & Dependency Cleanup

A toolchain that replicates what Knip does for JS/TS — detect unused code, unused dependencies, missing dependencies, and dead exports — but for PHP/WordPress plugin and theme development.

Toolchain Overview

Tool	Purpose	Detects
composer-unused	Unused Composer packages	Packages in require/require-dev never referenced in code
composer-require-checker	Missing Composer packages	Packages used in code but not declared in composer.json
Psalm --find-unused-code	Dead PHP code	Unused classes, methods, functions, properties, variables
PHP-CS-Fixer	Unused use imports	use statements at the top of files that aren't referenced
PHP_CodeSniffer	Unused imports (alt)	Same as above, alternative tool

Installation

All Tools at Once

composer require --dev \
  icanhazstring/composer-unused \
  maglnet/composer-require-checker \
  vimeo/psalm \
  php-stubs/wordpress-stubs \
  friendsofphp/php-cs-fixer

Individual Installation

# Unused dependency detection
composer require --dev icanhazstring/composer-unused

# Missing dependency detection
composer require --dev maglnet/composer-require-checker

# Static analysis + dead code detection
composer require --dev vimeo/psalm
composer require --dev php-stubs/wordpress-stubs

# Unused import cleanup
composer require --dev friendsofphp/php-cs-fixer

Tool 1: composer-unused — Unused Dependencies

Detects Composer packages listed in composer.json that are never referenced anywhere in the codebase.

Usage

# Basic scan
composer unused

# JSON output for parsing
composer unused --output-format=json

# Exclude specific packages from the check
composer unused --excludePackage=php-stubs/wordpress-stubs

# Only check runtime dependencies (skip dev)
composer unused --no-dev

Configuration (composer-unused.php)

<?php

declare(strict_types=1);

use ComposerUnused\ComposerUnused\Configuration\Configuration;
use ComposerUnused\ComposerUnused\Configuration\NamedFilter;
use ComposerUnused\ComposerUnused\Configuration\PatternFilter;

return static function (Configuration $config): Configuration {
    return $config
        // Packages used dynamically or via WordPress hooks
        ->addNamedFilter(NamedFilter::fromString('php-stubs/wordpress-stubs'))
        ->addNamedFilter(NamedFilter::fromString('wpackagist-plugin/some-plugin'))
        // Ignore all packages matching a pattern
        ->addPatternFilter(PatternFilter::fromString('/^ext-/'));
};