--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Tests\Argument;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\DependencyInjection\Argument\RewindableGenerator;
+
+class RewindableGeneratorTest extends TestCase
+{
+ public function testImplementsCountable()
+ {
+ $this->assertInstanceOf(\Countable::class, new RewindableGenerator(function () {
+ yield 1;
+ }, 1));
+ }
+
+ public function testCountUsesProvidedValue()
+ {
+ $generator = new RewindableGenerator(function () {
+ yield 1;
+ }, 3);
+
+ $this->assertCount(3, $generator);
+ }
+
+ public function testCountUsesProvidedValueAsCallback()
+ {
+ $called = 0;
+ $generator = new RewindableGenerator(function () {
+ yield 1;
+ }, function () use (&$called) {
+ ++$called;
+
+ return 3;
+ });
+
+ $this->assertSame(0, $called, 'Count callback is called lazily');
+ $this->assertCount(3, $generator);
+
+ count($generator);
+
+ $this->assertSame(1, $called, 'Count callback is called only once');
+ }
+}