getFileExtension()); self::assertEquals('application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', $sut->getContentType()); $spreadsheet = new Spreadsheet(); $file = $sut->save($spreadsheet); self::assertInstanceOf(\SplFileInfo::class, $file); self::assertTrue(file_exists($file->getRealPath())); // TODO test autofilter // TODO test freeze pane } }