/**
  * Empty strings or anything that is not a string is ignored without error
  *
  * @dataProvider	provideInvalidStrings
  * @depends			testAddFileGetFiles
  * @return		null
  */
 public function testAddFilesInvalidFiles($file)
 {
     $this->assertSame($this->dependency, $this->dependency->addFile($file), 'uses a fluent interface');
     $this->assertEquals(array(), $this->dependency->getFiles());
 }