Developer
<?php
/*
* This file is part of Psy Shell.
*
* (c) 2012-2023 Justin Hileman
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Psy\CodeCleaner;
use PhpParser\Node;
use PhpParser\Node\Expr\ArrayDimFetch;
use PhpParser\Node\Expr\Assign;
use PhpParser\Node\Expr\AssignRef;
use PhpParser\Node\Stmt\Foreach_;
use Psy\Exception\FatalErrorException;
/**
* Validate empty brackets are only used for assignment.
*/
class EmptyArrayDimFetchPass extends CodeCleanerPass
{
const EXCEPTION_MESSAGE = 'Cannot use [] for reading';
private $theseOnesAreFine = [];
/**
* @return Node[]|null Array of nodes
*/
public function beforeTraverse(array $nodes)
{
$this->theseOnesAreFine = [];
}
/**
* @throws FatalErrorException if the user used empty array dim fetch outside of assignment
*
* @param Node $node
*
* @return int|Node|null Replacement node (or special return value)
*/
public function enterNode(Node $node)
{
if ($node instanceof Assign && $node->var instanceof ArrayDimFetch) {
$this->theseOnesAreFine[] = $node->var;
} elseif ($node instanceof AssignRef && $node->expr instanceof ArrayDimFetch) {
$this->theseOnesAreFine[] = $node->expr;
} elseif ($node instanceof Foreach_ && $node->valueVar instanceof ArrayDimFetch) {
$this->theseOnesAreFine[] = $node->valueVar;
} elseif ($node instanceof ArrayDimFetch && $node->var instanceof ArrayDimFetch) {
// $a[]['b'] = 'c'
if (\in_array($node, $this->theseOnesAreFine)) {
$this->theseOnesAreFine[] = $node->var;
}
}
if ($node instanceof ArrayDimFetch && $node->dim === null) {
if (!\in_array($node, $this->theseOnesAreFine)) {
throw new FatalErrorException(self::EXCEPTION_MESSAGE, $node->getStartLine());
}
}
}
}
Developer
To ensure a smooth integration process and optimal performance, follow these best practices: