class DownloadTest

class DownloadTest extends FileTestBase {

  /**
   * {@inheritdoc}
   */
  protected static $modules = [
    'system',
  ];

  /**
   * {@inheritdoc}
   */
  protected function setUp() : void {
    parent::setUp();
    $this->container
      ->get('stream_wrapper_manager')
      ->registerWrapper('temporary', 'Drupal\\Core\\StreamWrapper\\TemporaryStream', StreamWrapperInterface::LOCAL_NORMAL);
  }

  /**
   * Tests a download that overwrites an existing local file.
   */
  public function testOverwritingDownload() {

    // Create a pre-existing file at the destination.
    $destination_uri = $this
      ->createUri('existing_file.txt');

    // Test destructive download.
    $actual_destination = $this
      ->doTransform($destination_uri);
    $this
      ->assertSame($destination_uri, $actual_destination, 'Import returned a destination that was not renamed');
    $this
      ->assertFileDoesNotExist('public://existing_file_0.txt');
  }

  /**
   * Tests a download that renames the downloaded file if there's a collision.
   */
  public function testNonDestructiveDownload() {

    // Create a pre-existing file at the destination.
    $destination_uri = $this
      ->createUri('another_existing_file.txt');

    // Test non-destructive download.
    $actual_destination = $this
      ->doTransform($destination_uri, [
      'file_exists' => 'rename',
    ]);
    $this
      ->assertSame('public://another_existing_file_0.txt', $actual_destination, 'Import returned a renamed destination');
    $this
      ->assertFileExists($actual_destination);
  }

  /**
   * Tests that an exception is thrown if the destination URI is not writable.
   */
  public function testWriteProtectedDestination() {

    // Create a pre-existing file at the destination.
    $destination_uri = $this
      ->createUri('not-writable.txt');

    // Make the destination non-writable.
    $this->container
      ->get('file_system')
      ->chmod($destination_uri, 0444);

    // Pass or fail, we'll need to make the file writable again so the test
    // can clean up after itself.
    $fix_permissions = function () use ($destination_uri) {
      $this->container
        ->get('file_system')
        ->chmod($destination_uri, 0755);
    };
    try {
      $this
        ->doTransform($destination_uri);
      $fix_permissions();
      $this
        ->fail('MigrateException was not thrown for non-writable destination URI.');
    } catch (MigrateException $e) {
      $this
        ->assertTrue(TRUE, 'MigrateException was thrown for non-writable destination URI.');
      $fix_permissions();
    }
  }

  /**
   * Runs an input value through the download plugin.
   *
   * @param string $destination_uri
   *   The destination URI to download to.
   * @param array $configuration
   *   (optional) Configuration for the download plugin.
   *
   * @return string
   *   The local URI of the downloaded file.
   */
  protected function doTransform($destination_uri, $configuration = []) {

    // Prepare a mock HTTP client.
    $this->container
      ->set('http_client', $this
      ->createMock(Client::class));

    // Instantiate the plugin statically so it can pull dependencies out of
    // the container.
    $plugin = Download::create($this->container, $configuration, 'download', []);

    // Execute the transformation.
    $executable = $this
      ->createMock(MigrateExecutableInterface::class);
    $row = new Row([], []);

    // Return the downloaded file's local URI.
    $value = [
      'http://drupal.org/favicon.ico',
      $destination_uri,
    ];

    // Assert that number of stream resources in use is the same before and
    // after the download.
    $initial_count = count(get_resources('stream'));
    $return = $plugin
      ->transform($value, $executable, $row, 'foo');
    $this
      ->assertCount($initial_count, get_resources('stream'));
    return $return;
  }

}