<?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;
use PhpParser\Node\Expr\FuncCall;
use PhpParser\Node\Expr\Variable;
use PhpParser\Node\Stmt\Do_;
use PhpParser\Node\Stmt\Function_;
use PhpParser\Node\Stmt\If_;
use PhpParser\Node\Stmt\Switch_;
use PhpParser\Node\Stmt\While_;
use Psy\Exception\FatalErrorException;
/**
* Validate that function calls will succeed.
*
* This pass throws a FatalErrorException rather than letting PHP run
* headfirst into a real fatal error and die.
*/
class ValidFunctionNamePass extends NamespaceAwarePass
{
private $conditionalScopes = 0;
/**
* Store newly defined function names on the way in, to allow recursion.
*
* @param Node $node
*/
public function enterNode(Node $node)
{
parent::enterNode($node);
if (self::isConditional($node)) {
$this->conditionalScopes++;
} elseif ($node instanceof Function_) {
$name = $this->getFullyQualifiedName($node->name);
// @todo add an "else" here which adds a runtime check for instances where we can't tell
// whether a function is being redefined by static analysis alone.
if ($this->conditionalScopes === 0) {
if (\function_exists($name) ||
isset($this->currentScope[\strtolower($name)])) {
$msg = \sprintf('Cannot redeclare %s()', $name);
throw new FatalErrorException($msg, 0, E_ERROR, null, $node->getLine());
}
}
$this->currentScope[\strtolower($name)] = true;
}
}
/**
* Validate that function calls will succeed.
*
* @throws FatalErrorException if a function is redefined
* @throws FatalErrorException if the function name is a string (not an expression) and is not defined
*
* @param Node $node
*/
public function leaveNode(Node $node)
{
if (self::isConditional($node)) {
$this->conditionalScopes--;
} elseif ($node instanceof FuncCall) {
// if function name is an expression or a variable, give it a pass for now.
$name = $node->name;
if (!$name instanceof Expr && !$name instanceof Variable) {
$shortName = \implode('\\', $name->parts);
$fullName = $this->getFullyQualifiedName($name);
$inScope = isset($this->currentScope[\strtolower($fullName)]);
if (!$inScope && !\function_exists($shortName) && !\function_exists($fullName)) {
$message = \sprintf('Call to undefined function %s()', $name);
throw new FatalErrorException($message, 0, E_ERROR, null, $node->getLine());
}
}
}
}
private static function isConditional(Node $node)
{
return $node instanceof If_ ||
$node instanceof While_ ||
$node instanceof Do_ ||
$node instanceof Switch_;
}
}