wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\Lib\Formatters;

use InvalidArgumentException;
use ValueFormatters\ValueFormatter;

/**
 * EscapingValueFormatter wraps another ValueFormatter and
 * applies a transformation (escaping) to that formatter's output.
 *
 * @license GPL-2.0-or-later
 * @author Daniel Kinzler
 */
class EscapingValueFormatter implements ValueFormatter {

    /**
     * @var ValueFormatter
     */
    private $formatter;

    /**
     * @var callable
     */
    private $escapeCallback;

    /**
     * @param ValueFormatter $formatter A formatter returning plain text.
     * @param callable $escapeCallback A callable taking plain text and returning escaped text.
     *
     * @throws InvalidArgumentException
     */
    public function __construct( ValueFormatter $formatter, $escapeCallback ) {
        if ( !is_callable( $escapeCallback ) ) {
            throw new InvalidArgumentException( '$escapeCallback must be callable' );
        }

        $this->formatter = $formatter;
        $this->escapeCallback = $escapeCallback;
    }

    /**
     * @see ValueFormatter::format
     *
     * @param mixed $value
     *
     * @return string Typically wikitext or HTML, depending on the $escapeCallback provided.
     */
    public function format( $value ) {
        $text = $this->formatter->format( $value );
        $escaped = call_user_func( $this->escapeCallback, $text );
        return $escaped;
    }

}