RequireNullCoalesceEqualOperatorSniff.php

<?php

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

use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use PHP_CodeSniffer\Util\Tokens;
use SlevomatCodingStandard\Helpers\FixerHelper;
use SlevomatCodingStandard\Helpers\IdentificatorHelper;
use SlevomatCodingStandard\Helpers\SniffSettingsHelper;
use SlevomatCodingStandard\Helpers\TokenHelper;
use const T_COALESCE;
use const T_EQUAL;
use const T_SEMICOLON;
class RequireNullCoalesceEqualOperatorSniff implements Sniff {
    public const CODE_REQUIRED_NULL_COALESCE_EQUAL_OPERATOR = 'RequiredNullCoalesceEqualOperator';
    
    /** @var bool|null */
    public $enable = null;
    
    /**
     * @return array<int, (int|string)>
     */
    public function register() : array {
        return [
            T_EQUAL,
        ];
    }
    
    /**
     * @phpcsSuppress SlevomatCodingStandard.TypeHints.ParameterTypeHint.MissingNativeTypeHint
     * @param int $equalPointer
     */
    public function process(File $phpcsFile, $equalPointer) : void {
        $this->enable = SniffSettingsHelper::isEnabledByPhpVersion($this->enable, 70400);
        if (!$this->enable) {
            return;
        }
        
        /** @var int $variableStartPointer */
        $variableStartPointer = TokenHelper::findNextEffective($phpcsFile, $equalPointer + 1);
        $variableEndPointer = IdentificatorHelper::findEndPointer($phpcsFile, $variableStartPointer);
        if ($variableEndPointer === null) {
            return;
        }
        $nullCoalescePointer = TokenHelper::findNextEffective($phpcsFile, $variableEndPointer + 1);
        $tokens = $phpcsFile->getTokens();
        if ($tokens[$nullCoalescePointer]['code'] !== T_COALESCE) {
            return;
        }
        $variableContent = IdentificatorHelper::getContent($phpcsFile, $variableStartPointer, $variableEndPointer);
        
        /** @var int $beforeEqualEndPointer */
        $beforeEqualEndPointer = TokenHelper::findPreviousEffective($phpcsFile, $equalPointer - 1);
        $beforeEqualStartPointer = IdentificatorHelper::findStartPointer($phpcsFile, $beforeEqualEndPointer);
        if ($beforeEqualStartPointer === null) {
            return;
        }
        $beforeEqualVariableContent = IdentificatorHelper::getContent($phpcsFile, $beforeEqualStartPointer, $beforeEqualEndPointer);
        if ($beforeEqualVariableContent !== $variableContent) {
            return;
        }
        $semicolonPointer = TokenHelper::findNext($phpcsFile, T_SEMICOLON, $equalPointer + 1);
        if (TokenHelper::findNext($phpcsFile, Tokens::$operators, $nullCoalescePointer + 1, $semicolonPointer) !== null) {
            return;
        }
        $fix = $phpcsFile->addFixableError('Use "??=" operator instead of "=" and "??".', $equalPointer, self::CODE_REQUIRED_NULL_COALESCE_EQUAL_OPERATOR);
        if (!$fix) {
            return;
        }
        $phpcsFile->fixer
            ->beginChangeset();
        FixerHelper::change($phpcsFile, $equalPointer, $nullCoalescePointer, '??=');
        $phpcsFile->fixer
            ->endChangeset();
    }

}