public function testIsConvertingToCleanUrl()
 {
     $string = new String('Your mother is so ugly, glCullFace always returns TRUE.');
     $result = $string->toCleanUrl();
     $this->assertInstanceOf('Simple\\Type\\String', $result);
     $this->assertEquals('your-mother-is-so-ugly-glcullface-always-returns-true', $result->toString());
     $string = new String('Your mother is so ugly, glCullFace always returns TRUE.');
     $result = $string->toCleanUrl('_');
     $this->assertInstanceOf('Simple\\Type\\String', $result);
     $this->assertEquals('your_mother_is_so_ugly_glcullface_always_returns_true', $result->toString());
     $string = new String('Acentos serão reconhecidos e substituídos.');
     $result = $string->toCleanUrl();
     $this->assertInstanceOf('Simple\\Type\\String', $result);
     $this->assertEquals('acentos-serao-reconhecidos-e-substituidos', $result->toString());
 }