<?php
/*
* This file is part of Twig.
*
* (c) Fabien Potencier
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Twig\Node\Expression\Test;
use Twig\Compiler;
use Twig\Error\SyntaxError;
use Twig\Node\Expression\ArrayExpression;
use Twig\Node\Expression\BlockReferenceExpression;
use Twig\Node\Expression\ConstantExpression;
use Twig\Node\Expression\FunctionExpression;
use Twig\Node\Expression\GetAttrExpression;
use Twig\Node\Expression\MethodCallExpression;
use Twig\Node\Expression\NameExpression;
use Twig\Node\Expression\TestExpression;
use Twig\Node\Node;
/**
* Checks if a variable is defined in the current context.
*
* {# defined works with variable names and variable attributes #}
* {% if foo is defined %}
* {# ... #}
* {% endif %}
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class DefinedTest extends TestExpression
{
public function __construct(Node $node, string $name, ?Node $arguments, int $lineno)
{
if ($node instanceof NameExpression) {
$node->setAttribute('is_defined_test', true);
} elseif ($node instanceof GetAttrExpression) {
$node->setAttribute('is_defined_test', true);
$this->changeIgnoreStrictCheck($node);
} elseif ($node instanceof BlockReferenceExpression) {
$node->setAttribute('is_defined_test', true);
} elseif ($node instanceof FunctionExpression && 'constant' === $node->getAttribute('name')) {
$node->setAttribute('is_defined_test', true);
} elseif ($node instanceof ConstantExpression || $node instanceof ArrayExpression) {
$node = new ConstantExpression(true, $node->getTemplateLine());
} elseif ($node instanceof MethodCallExpression) {
$node->setAttribute('is_defined_test', true);
} else {
throw new SyntaxError('The "defined" test only works with simple variables.', $lineno);
}
parent::__construct($node, $name, $arguments, $lineno);
}
private function changeIgnoreStrictCheck(GetAttrExpression $node)
{
$node->setAttribute('optimizable', false);
$node->setAttribute('ignore_strict_check', true);
if ($node->getNode('node') instanceof GetAttrExpression) {
$this->changeIgnoreStrictCheck($node->getNode('node'));
}
}
public function compile(Compiler $compiler): void
{
$compiler->subcompile($this->getNode('node'));
}
}