Custom PHPStan rule to disallow catching \Throwable exception

DisallowCatchingThrowableExceptionRule.php

<?php

declare(strict_types=1);

namespace App\PHPStan\Rules;

use PhpParser\Node;
use PhpParser\Node\Stmt;
use PHPStan\Analyser\Scope;
use PHPStan\Rules\Rule;

/**
 * @implements Rule<Stmt>
 */
class DisallowCatchingThrowableExceptionRule implements Rule
{
    private const THROWABLE_NODE_ATTRIBUTE = '__THROWABLE_NODE_ATTRIBUTE__';

    public function getNodeType(): string
    {
        return Stmt::class;
    }

    /**
     * @return string[]
     */
    public function processNode(Node $node, Scope $scope): array
    {
        if ($node instanceof Stmt\TryCatch) {
            foreach ($node->catches as $catch) {
                $catchClasses = array_map(static function (Node\Name $node): string {
                    return $node->toString();
                }, $catch->types);

                if (!in_array(\Throwable::class, $catchClasses, true)) {
                    continue;
                }

                $catch->setAttribute(self::THROWABLE_NODE_ATTRIBUTE, 'You cannot catch the \Throwable exception');

                break;
            }

            return [];
        }

        if ($node instanceof Stmt\Catch_ && $node->hasAttribute(self::THROWABLE_NODE_ATTRIBUTE)) {
            return [$node->getAttribute(self::THROWABLE_NODE_ATTRIBUTE)];
        }

        return [];
    }
}