DisallowYodaComparisonSniff.php

<?php

declare (strict_types=1);
namespace SlevomatCodingStandard\Sniffs\ControlStructures;

use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use SlevomatCodingStandard\Helpers\TokenHelper;
use SlevomatCodingStandard\Helpers\YodaHelper;
use function array_keys;
use function count;
use const T_EQUAL;
use const T_IS_EQUAL;
use const T_IS_IDENTICAL;
use const T_IS_NOT_EQUAL;
use const T_IS_NOT_IDENTICAL;

/**
 * Bigger value must be on the left side:
 *
 * ($variable, Foo::$class, Foo::bar(), foo())
 *  > (Foo::BAR, BAR)
 *  > (true, false, null, 1, 1.0, arrays, 'foo')
 */
class DisallowYodaComparisonSniff implements Sniff {
    public const CODE_DISALLOWED_YODA_COMPARISON = 'DisallowedYodaComparison';
    
    /**
     * @return array<int, (int|string)>
     */
    public function register() : array {
        return [
            T_IS_IDENTICAL,
            T_IS_NOT_IDENTICAL,
            T_IS_EQUAL,
            T_IS_NOT_EQUAL,
        ];
    }
    
    /**
     * @phpcsSuppress SlevomatCodingStandard.TypeHints.ParameterTypeHint.MissingNativeTypeHint
     * @param int $comparisonTokenPointer
     */
    public function process(File $phpcsFile, $comparisonTokenPointer) : void {
        $tokens = $phpcsFile->getTokens();
        $leftSideTokens = YodaHelper::getLeftSideTokens($tokens, $comparisonTokenPointer);
        $rightSideTokens = YodaHelper::getRightSideTokens($tokens, $comparisonTokenPointer);
        $leftDynamism = YodaHelper::getDynamismForTokens($tokens, $leftSideTokens);
        $rightDynamism = YodaHelper::getDynamismForTokens($tokens, $rightSideTokens);
        if ($leftDynamism === null || $rightDynamism === null) {
            return;
        }
        if ($leftDynamism >= $rightDynamism) {
            return;
        }
        if ($leftDynamism >= 900 && $rightDynamism >= 900) {
            return;
        }
        $errorParameters = [
            'Yoda comparisons are disallowed.',
            $comparisonTokenPointer,
            self::CODE_DISALLOWED_YODA_COMPARISON,
        ];
        $lastRightSideTokenPointer = array_keys($rightSideTokens)[count($rightSideTokens) - 1];
        $nextPointer = TokenHelper::findNextEffective($phpcsFile, $lastRightSideTokenPointer + 1);
        if ($tokens[$nextPointer]['code'] === T_EQUAL) {
            $phpcsFile->addError(...$errorParameters);
            return;
        }
        $fix = $phpcsFile->addFixableError(...$errorParameters);
        if (!$fix) {
            return;
        }
        YodaHelper::fix($phpcsFile, $leftSideTokens, $rightSideTokens);
    }

}