InlineIfToExplicitIfRector.php

<?php

declare(strict_types=1);

namespace Rector\CodeQuality\Rector\Expression;

use PhpParser\Node;
use PhpParser\Node\Expr;
use PhpParser\Node\Expr\BinaryOp\BooleanAnd;
use PhpParser\Node\Expr\BinaryOp\BooleanOr;
use PhpParser\Node\Expr\BooleanNot;
use PhpParser\Node\Expr\FuncCall;
use PhpParser\Node\Expr\MethodCall;
use PhpParser\Node\Expr\Variable;
use PhpParser\Node\Stmt\Expression;
use PhpParser\Node\Stmt\If_;
use Rector\NodeManipulator\BinaryOpManipulator;
use Rector\Rector\AbstractRector;
use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;

/**
 * @see \Rector\Tests\CodeQuality\Rector\Expression\InlineIfToExplicitIfRector\InlineIfToExplicitIfRectorTest
 */
final class InlineIfToExplicitIfRector extends AbstractRector
{
    public function __construct(
        private readonly BinaryOpManipulator $binaryOpManipulator
    ) {
    }

    public function getRuleDefinition(): RuleDefinition
    {
        return new RuleDefinition('Change inline if to explicit if', [
            new CodeSample(
                <<<'CODE_SAMPLE'
class SomeClass
{
    public function run()
    {
        $userId = null;

        is_null($userId) && $userId = 5;
    }
}
CODE_SAMPLE
                ,
                <<<'CODE_SAMPLE'
class SomeClass
{
    public function run()
    {
        $userId = null;

        if (is_null($userId)) {
            $userId = 5;
        }
    }
}
CODE_SAMPLE
            ),
        ]);
    }

    /**
     * @return array<class-string<Node>>
     */
    public function getNodeTypes(): array
    {
        return [Expression::class];
    }

    /**
     * @param Expression $node
     */
    public function refactor(Node $node): ?Node
    {
        if ($node->expr instanceof BooleanAnd) {
            return $this->processExplicitIf($node);
        }

        if ($node->expr instanceof BooleanOr) {
            return $this->processExplicitIf($node);
        }

        return null;
    }

    private function processExplicitIf(Expression $expression): ?Node
    {
        /** @var BooleanAnd|BooleanOr $booleanExpr */
        $booleanExpr = $expression->expr;

        $exprLeft = $booleanExpr->left instanceof BooleanNot
            ? $booleanExpr->left->expr
            : $booleanExpr->left;

        if ($exprLeft instanceof FuncCall && $this->isName($exprLeft, 'defined')) {
            return null;
        }

        if ($this->isSameLocalMethodCallChain($booleanExpr)) {
            return null;
        }

        $leftStaticType = $this->getType($booleanExpr->left);
        if (! $leftStaticType->isBoolean()->yes()) {
            return null;
        }

        /** @var Expr $expr */
        $expr = $booleanExpr instanceof BooleanAnd
            ? $booleanExpr->left
            : $this->binaryOpManipulator->inverseNode($booleanExpr->left);
        $if = new If_($expr);
        $if->stmts[] = new Expression($booleanExpr->right);

        $this->mirrorComments($if, $expression);
        return $if;
    }

    private function isSameLocalMethodCallChain(BooleanAnd|BooleanOr $booleanExpr): bool
    {
        $leaves = $this->collectOperands($booleanExpr);

        $firstMethodCall = null;
        foreach ($leaves as $leaf) {
            if (! $leaf instanceof MethodCall) {
                return false;
            }

            if (! $leaf->var instanceof Variable || ! $this->isName($leaf->var, 'this')) {
                return false;
            }

            if (! $firstMethodCall instanceof MethodCall) {
                $firstMethodCall = $leaf;
                continue;
            }

            if (! $this->nodeNameResolver->areNamesEqual($firstMethodCall->name, $leaf->name)) {
                return false;
            }
        }

        return $firstMethodCall instanceof MethodCall;
    }

    /**
     * @return Expr[]
     */
    private function collectOperands(Expr $expr): array
    {
        if ($expr instanceof BooleanAnd || $expr instanceof BooleanOr) {
            return array_merge($this->collectOperands($expr->left), $this->collectOperands($expr->right));
        }

        return [$expr];
    }
}