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() : void {
        // 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() : void {
        // 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() : void {
        // 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) {
            $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;
    }

}