TernaryEmptyArrayArrayDimFetchToCoalesceRector.php

<?php

declare (strict_types=1);
namespace Rector\CodeQuality\Rector\Ternary;

use PhpParser\Node;
use PhpParser\Node\Expr\ArrayDimFetch;
use PhpParser\Node\Expr\BinaryOp\Coalesce;
use PhpParser\Node\Expr\BooleanNot;
use PhpParser\Node\Expr\Empty_;
use PhpParser\Node\Expr\Ternary;
use Rector\Rector\AbstractRector;
use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
/**
 * @see \Rector\Tests\CodeQuality\Rector\Ternary\TernaryEmptyArrayArrayDimFetchToCoalesceRector\TernaryEmptyArrayArrayDimFetchToCoalesceRectorTest
 */
final class TernaryEmptyArrayArrayDimFetchToCoalesceRector extends AbstractRector
{
    public function getRuleDefinition() : RuleDefinition
    {
        return new RuleDefinition('Change ternary empty on array property with array dim fetch to coalesce operator', [new CodeSample(<<<'CODE_SAMPLE'
final class SomeClass
{
    private array $items = [];

    public function run()
    {
        return ! empty($this->items) ? $this->items[0] : 'default';
    }
}
CODE_SAMPLE
, <<<'CODE_SAMPLE'
final class SomeClass
{
    private array $items = [];

    public function run()
    {
        return $this->items[0] ?? 'default';
    }
}
CODE_SAMPLE
)]);
    }
    /**
     * @return array<class-string<Node>>
     */
    public function getNodeTypes() : array
    {
        return [Ternary::class];
    }
    /**
     * @param Ternary $node
     */
    public function refactor(Node $node) : ?Node
    {
        if (!$node->cond instanceof BooleanNot) {
            return null;
        }
        $negagedExpr = $node->cond->expr;
        if (!$negagedExpr instanceof Empty_) {
            return null;
        }
        if (!$node->if instanceof ArrayDimFetch) {
            return null;
        }
        $emptyExprType = $this->getType($negagedExpr->expr);
        if (!$emptyExprType->isArray()->yes()) {
            return null;
        }
        $dimFetchVar = $node->if->var;
        if (!$this->nodeComparator->areNodesEqual($negagedExpr->expr, $dimFetchVar)) {
            return null;
        }
        return new Coalesce($node->if, $node->else);
    }
}