<?php
/*
* This file is part of Psy Shell.
*
* (c) 2012-2020 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\Yield_;
use PhpParser\Node\FunctionLike;
use Psy\Exception\FatalErrorException;
class FunctionContextPass extends CodeCleanerPass
{
/** @var int */
private $functionDepth;
/**
* @param array $nodes
*/
public function beforeTraverse(array $nodes)
{
$this->functionDepth = 0;
}
public function enterNode(Node $node)
{
if ($node instanceof FunctionLike) {
$this->functionDepth++;
return;
}
// node is inside function context
if ($this->functionDepth !== 0) {
return;
}
// It causes fatal error.
if ($node instanceof Yield_) {
$msg = 'The "yield" expression can only be used inside a function';
throw new FatalErrorException($msg, 0, E_ERROR, null, $node->getLine());
}
}
/**
* @param \PhpParser\Node $node
*/
public function leaveNode(Node $node)
{
if ($node instanceof FunctionLike) {
$this->functionDepth--;
}
}
}