DeduplicateStyles.php
No OneTemporary
Actions

Size

1 KB

Referenced Files

None

Subscribers

None

DeduplicateStyles.php
View Options

	<?php

	namespace MediaWiki\OutputTransform\Stages;

	use MediaWiki\Html\Html;
	use MediaWiki\OutputTransform\ContentTextTransformStage;
	use MediaWiki\Parser\ParserOptions;
	use MediaWiki\Parser\ParserOutput;
	use MediaWiki\Parser\Sanitizer;

	/**
	* Generates a list of unique style links
	* @internal
	*/
	class DeduplicateStyles extends ContentTextTransformStage {

	public function shouldRun( ParserOutput $po, ?ParserOptions $popts, array $options = [] ): bool {
	return $options['deduplicateStyles'] ?? true;
	}

	protected function transformText( string $text, ParserOutput $po, ?ParserOptions $popts, array &$options ): string {
	$seen = [];
	return preg_replace_callback( '#<style\s+([^>]data-mw-deduplicate\s=[\'"][^>])>.?</style>#s',
	static function ( $m ) use ( &$seen ) {
	$attr = Sanitizer::decodeTagAttributes( $m[1] );
	if ( !isset( $attr['data-mw-deduplicate'] ) ) {
	return $m[0];
	}

	$key = $attr['data-mw-deduplicate'];
	if ( !isset( $seen[$key] ) ) {
	$seen[$key] = true;

	return $m[0];
	}

	// We were going to use an empty <style> here, but there
	// was concern that would be too much overhead for browsers.
	// So let's hope a <link> with a non-standard rel and href isn't
	// going to be misinterpreted or mangled by any subsequent processing.
	return Html::element( 'link', [
	'rel' => 'mw-deduplicated-inline-style',
	'href' => "mw-data:" . wfUrlencode( $key ),
	] );
	}, $text );
	}
	}