class AssetXssTest

class AssetXssTest extends BrowserTestBase {
  
  /**
   * {@inheritdoc}
   */
  protected $profile = 'minimal';
  
  /**
   * {@inheritdoc}
   */
  protected $defaultTheme = 'stark';
  
  /**
   * A dataProvider for JS and CSS asset tests.
   *
   * @return array
   *   - Array of inputs for the test URL
   */
  public static function providerAssetUrl() {
    $query = [
      'language' => 'en',
      'delta' => 1,
      'theme' => 'drupal',
      'include' => '<img src=x onerror=alert("xss")>',
    ];
    return [
      [
        'path' => '/js/js_foo.js',
        'query' => $query,
      ],
      [
        'path' => '/css/css_foo.css',
        'query' => $query,
      ],
    ];
  }
  
  /**
   * Test sanitization of the error message for an invalid asset.
   *
   * @throws \Behat\Mink\Exception\ExpectationException
   */
  public function testAssetUrl($path, $query) : void {
    $path = PublicStream::basePath() . $path;
    $this->drupalGet($path, [
      'query' => $query,
    ]);
    $this->assertSession()
      ->statusCodeEquals(400);
    $this->assertSession()
      ->responseContains('library name must include at least one slash');
    $this->assertSession()
      ->elementNotExists('xpath', '//img[contains(@onerror, "alert")]');
    // Swap the XSS payload into the exclude parameter.
    $query['exclude'] = $query['include'];
    $query['include'] = 'foo/bar';
    $this->drupalGet($path, [
      'query' => $query,
    ]);
    $this->assertSession()
      ->statusCodeEquals(400);
    $this->assertSession()
      ->responseContains('library name must include at least one slash');
    $this->assertSession()
      ->elementNotExists('xpath', '//img[contains(@onerror, "alert")]');
  }

}