class TestDiscoveryCacheContextTest

class TestDiscoveryCacheContextTest extends KernelTestBase {
  
  /**
   * {@inheritdoc}
   */
  public static $modules = [
    'simpletest',
  ];
  
  /**
   * Tests that test context hashes are unique.
   *
   * @expectedDeprecation Drupal\simpletest\TestDiscovery is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use \Drupal\Core\Test\TestDiscovery instead. See https://www.drupal.org/node/2949692
   */
  public function testContext() {
    // Mock test discovery.
    $discovery = $this->getMockBuilder(TestDiscovery::class)
      ->setMethods([
      'getTestClasses',
    ])
      ->disableOriginalConstructor()
      ->getMock();
    // Set getTestClasses() to return different results on subsequent calls.
    // This emulates changed tests in the filesystem.
    $discovery->expects($this->any())
      ->method('getTestClasses')
      ->willReturnOnConsecutiveCalls([
      'group1' => [
        'Test',
      ],
    ], [
      'group2' => [
        'Test2',
      ],
    ]);
    // Make our cache context object.
    $cache_context = new TestDiscoveryCacheContext($discovery, $this->container
      ->get('private_key'));
    // Generate a context hash.
    $context_hash = $cache_context->getContext();
    // Since the context stores the hash, we have to reset it.
    $hash_ref = new \ReflectionProperty($cache_context, 'hash');
    $hash_ref->setAccessible(TRUE);
    $hash_ref->setValue($cache_context, NULL);
    // And then assert that we did not generate the same hash for different
    // content.
    $this->assertNotSame($context_hash, $cache_context->getContext());
  }

}