generate-function-metadata.php

#!/usr/bin/env php
<?php declare(strict_types=1);

use PhpParser\Node;
use PhpParser\NodeTraverser;
use PhpParser\NodeVisitor\NameResolver;
use PhpParser\NodeVisitor\NodeConnectingVisitor;
use PhpParser\ParserFactory;

(function () {
	require_once __DIR__ . '/../vendor/autoload.php';

	$parser = (new ParserFactory())->create(ParserFactory::ONLY_PHP7);
	$finder = new Symfony\Component\Finder\Finder();
	$finder->in(__DIR__ . '/../vendor/jetbrains/phpstorm-stubs')->files()->name('*.php');

	$visitor = new class() extends \PhpParser\NodeVisitorAbstract {

		/** @var string[] */
		public $functions = [];

		/** @var string[] */
		public $methods = [];

		public function enterNode(Node $node)
		{
			if ($node instanceof Node\Stmt\Function_) {
				foreach ($node->attrGroups as $attrGroup) {
					foreach ($attrGroup->attrs as $attr) {
						if ($attr->name->toString() === \JetBrains\PhpStorm\Pure::class) {
							$this->functions[] = $node->namespacedName->toLowerString();
							break 2;
						}
					}
				}
			}

			if ($node instanceof Node\Stmt\ClassMethod) {
				$class = $node->getAttribute('parent');
				if (!$class instanceof Node\Stmt\ClassLike) {
					throw new \PHPStan\ShouldNotHappenException($node->name->toString());
				}
				$className = $class->namespacedName->toString();
				foreach ($node->attrGroups as $attrGroup) {
					foreach ($attrGroup->attrs as $attr) {
						if ($attr->name->toString() === \JetBrains\PhpStorm\Pure::class) {
							$this->methods[] = sprintf('%s::%s', $className, $node->name->toString());
							break 2;
						}
					}
				}
			}

			return null;
		}
	};

	foreach ($finder as $stubFile) {
		$path = $stubFile->getPathname();
		$traverser = new NodeTraverser();
		$traverser->addVisitor(new NameResolver());
		$traverser->addVisitor(new NodeConnectingVisitor());
		$traverser->addVisitor($visitor);

		$traverser->traverse(
			$parser->parse(\PHPStan\File\FileReader::read($path))
		);
	}

	$metadata = require __DIR__ . '/functionMetadata_original.php';
	foreach ($visitor->functions as $functionName) {
		if (array_key_exists($functionName, $metadata)) {
			if ($metadata[$functionName]['hasSideEffects']) {
				if (in_array($functionName, [
					'mt_rand',
					'rand',
					'random_bytes',
					'random_int',
				], true)) {
					continue;
				}
				throw new \PHPStan\ShouldNotHappenException($functionName);
			}
		}
		$metadata[$functionName] = ['hasSideEffects' => false];
	}

	foreach ($visitor->methods as $methodName) {
		if (array_key_exists($methodName, $metadata)) {
			if ($metadata[$methodName]['hasSideEffects']) {
				throw new \PHPStan\ShouldNotHappenException($methodName);
			}
		}
		$metadata[$methodName] = ['hasSideEffects' => false];
	}

	ksort($metadata);

	$template = <<<'php'
<?php declare(strict_types = 1);

return [
%s
];
php;
	$content = '';
	foreach ($metadata as $name => $meta) {
		$content .= sprintf(
			"\t%s => [%s => %s],\n",
			var_export($name, true),
			var_export('hasSideEffects', true),
			var_export($meta['hasSideEffects'], true),
		);
	}

	\PHPStan\File\FileWriter::write(__DIR__ . '/../resources/functionMetadata.php', sprintf($template, $content));

})();