Add Composer autoloading functions and PHPStan for testing

vendor/nikic/php-parser/test/PhpParser/ParserFactoryTest.php

@@ -0,0 +1,36 @@
+<?php declare(strict_types=1);
+
+namespace PhpParser;
+
+/* This test is very weak, because PHPUnit's assertEquals assertion is way too slow dealing with the
+ * large objects involved here. So we just do some basic instanceof tests instead. */
+
+class ParserFactoryTest extends \PHPUnit\Framework\TestCase
+{
+    /** @dataProvider provideTestCreate */
+    public function testCreate($kind, $lexer, $expected) {
+        $this->assertInstanceOf($expected, (new ParserFactory)->create($kind, $lexer));
+    }
+
+    public function provideTestCreate() {
+        $lexer = new Lexer();
+        return [
+            [
+                ParserFactory::PREFER_PHP7, $lexer,
+                Parser\Multiple::class
+            ],
+            [
+                ParserFactory::PREFER_PHP5, null,
+                Parser\Multiple::class
+            ],
+            [
+                ParserFactory::ONLY_PHP7, null,
+                Parser\Php7::class
+            ],
+            [
+                ParserFactory::ONLY_PHP5, $lexer,
+                Parser\Php5::class
+            ]
+        ];
+    }
+}