describe('#to - empty subfield', () => {
    it(`should not throw even if there's a subfield no value`, () => {
      const inputRecordJSON = fs.readFileSync(path.resolve(fixturesPath, 'valuelessSubfield'), 'utf8');
      const expectedRecord = fs.readFileSync(path.resolve(fixturesPath, 'emptySubAlephSeq'), 'utf8');
      const record = new MarcRecord(JSON.parse(inputRecordJSON));