<?php
/**
 * PHPCompatibility, an external standard for PHP_CodeSniffer.
 *
 * @package   PHPCompatibility
 * @copyright 2012-2019 PHPCompatibility Contributors
 * @license   https://opensource.org/licenses/LGPL-3.0 LGPL3
 * @link      https://github.com/PHPCompatibility/PHPCompatibility
 */

namespace PHPCompatibility\Sniffs\Constants;

use PHPCompatibility\Sniff;
use PHP_CodeSniffer_File as File;
use PHP_CodeSniffer_Tokens as Tokens;

/**
 * Detect usage of the magic `::class` constant introduced in PHP 5.5.
 *
 * The special `ClassName::class` constant is available as of PHP 5.5.0, and allows
 * for fully qualified class name resolution at compile time.
 *
 * PHP version 5.5
 *
 * @link https://wiki.php.net/rfc/class_name_scalars
 * @link https://www.php.net/manual/en/language.oop5.constants.php#example-186
 *
 * @since 7.1.4
 * @since 7.1.5 Removed the incorrect checks against invalid usage of the constant.
 */
class NewMagicClassConstantSniff extends Sniff {


	/**
	 * Returns an array of tokens this test wants to listen for.
	 *
	 * @since 7.1.4
	 *
	 * @return array
	 */
	public function register() {
		return array( \T_STRING );
	}

	/**
	 * Processes this test, when one of its tokens is encountered.
	 *
	 * @since 7.1.4
	 *
	 * @param \PHP_CodeSniffer_File $phpcsFile The file being scanned.
	 * @param int                   $stackPtr  The position of the current token in the
	 *                                         stack passed in $tokens.
	 *
	 * @return void
	 */
	public function process( File $phpcsFile, $stackPtr ) {
		if ( $this->supportsBelow( '5.4' ) === false ) {
			return;
		}

		$tokens = $phpcsFile->getTokens();

		if ( strtolower( $tokens[ $stackPtr ]['content'] ) !== 'class' ) {
			return;
		}

		$prevToken = $phpcsFile->findPrevious( Tokens::$emptyTokens, ( $stackPtr - 1 ), null, true, null, true );
		if ( $prevToken === false || $tokens[ $prevToken ]['code'] !== \T_DOUBLE_COLON ) {
			return;
		}

		$phpcsFile->addError(
			'The magic class constant ClassName::class was not available in PHP 5.4 or earlier',
			$stackPtr,
			'Found'
		);
	}
}
