public function testWriteFileContent()
 {
     $writer = $this->contentService->getWriterFor();
     $this->assertTrue($writer instanceof FileContentWriter);
     $writer->write(new FileContentReader(__FILE__), 'test_file.php');
     $id = $writer->getContentId();
     $this->assertNotNull($id);
     $this->assertTrue(strpos($id, 'test_file.php') > 0);
     $this->assertTrue(strpos($id, 'File:') === 0);
 }