php-extension-check/src/Parser/Visitors/FunctionCollector.php

<?php

declare(strict_types=1);

namespace Fbrinker\ExtensionCheck\Parser\Visitors;

use PhpParser\Node;
use PhpParser\NodeVisitorAbstract;

class FunctionCollector extends NodeVisitorAbstract implements CollectorInferface
{
    /**
    * @var array<string,bool> $functions
    */
    private $functions = [];

    public function getCollected(): array
    {
        $list = array_keys($this->functions);
        natcasesort($list);

        return array_values($list);
    }

    public function enterNode(Node $node)
    {
        if ($node instanceof Node\Expr\FuncCall) {
            if (!empty($node->name) && $node->name instanceof Node\Name) {
                $this->functions[$node->name->toString()] = true;
            }
        }

        return null;
    }
}