rector/packages/NodeTypeResolver/PHPStan/Scope/NodeVisitor/ByRefVariableNodeVisitor.php

<?php

declare (strict_types=1);
namespace Rector\NodeTypeResolver\PHPStan\Scope\NodeVisitor;

use PhpParser\Node;
use PhpParser\Node\Expr;
use PhpParser\Node\Expr\AssignRef;
use PhpParser\Node\Expr\Closure;
use PhpParser\Node\Expr\Variable;
use PhpParser\Node\FunctionLike;
use PhpParser\NodeVisitorAbstract;
use Rector\NodeTypeResolver\Node\AttributeKey;
use Rector\NodeTypeResolver\PHPStan\Scope\Contract\NodeVisitor\ScopeResolverNodeVisitorInterface;
use Rector\PhpDocParser\NodeTraverser\SimpleCallableNodeTraverser;
final class ByRefVariableNodeVisitor extends NodeVisitorAbstract implements ScopeResolverNodeVisitorInterface
{
    /**
     * @readonly
     * @var \Rector\PhpDocParser\NodeTraverser\SimpleCallableNodeTraverser
     */
    private $simpleCallableNodeTraverser;
    public function __construct(SimpleCallableNodeTraverser $simpleCallableNodeTraverser)
    {
        $this->simpleCallableNodeTraverser = $simpleCallableNodeTraverser;
    }
    public function enterNode(Node $node) : ?Node
    {
        if ($node instanceof AssignRef) {
            $node->expr->setAttribute(AttributeKey::IS_BYREF_VAR, \true);
            return null;
        }
        if (!$node instanceof FunctionLike) {
            return null;
        }
        $byRefVariableNames = $this->resolveClosureUseIsByRefAttribute($node, []);
        $byRefVariableNames = $this->resolveParamIsByRefAttribute($node, $byRefVariableNames);
        $stmts = $node->getStmts();
        if ($stmts === null) {
            return null;
        }
        $this->simpleCallableNodeTraverser->traverseNodesWithCallable($stmts, function (Node $subNode) use(&$byRefVariableNames) : ?\PhpParser\Node\Expr\Variable {
            if ($subNode instanceof Closure) {
                $byRefVariableNames = $this->resolveClosureUseIsByRefAttribute($subNode, $byRefVariableNames);
                return null;
            }
            if (!$subNode instanceof Variable) {
                return null;
            }
            if (!\in_array($subNode->name, $byRefVariableNames, \true)) {
                return null;
            }
            $subNode->setAttribute(AttributeKey::IS_BYREF_VAR, \true);
            return $subNode;
        });
        return null;
    }
    /**
     * @param string[] $byRefVariableNames
     * @return string[]
     */
    private function resolveParamIsByRefAttribute(FunctionLike $functionLike, array $byRefVariableNames) : array
    {
        foreach ($functionLike->getParams() as $param) {
            if ($param->byRef && $param->var instanceof Variable && !$param->var->name instanceof Expr) {
                $param->var->setAttribute(AttributeKey::IS_BYREF_VAR, \true);
                $byRefVariableNames[] = $param->var->name;
            }
        }
        return $byRefVariableNames;
    }
    /**
     * @param string[] $byRefVariableNames
     * @return string[]
     */
    private function resolveClosureUseIsByRefAttribute(FunctionLike $functionLike, array $byRefVariableNames) : array
    {
        if (!$functionLike instanceof Closure) {
            return $byRefVariableNames;
        }
        foreach ($functionLike->uses as $closureUse) {
            if ($closureUse->byRef && !$closureUse->var->name instanceof Expr) {
                $closureUse->var->setAttribute(AttributeKey::IS_BYREF_VAR, \true);
                $byRefVariableNames[] = $closureUse->var->name;
            }
        }
        return $byRefVariableNames;
    }
}