old_contents: #!/usr/bin/env node
  
  /**
   * @description File size checker.
   * @author sota1235
   */
  
  "use strict";
  
  import { create } from 'node-getopt';
  import glob from 'glob';
  import checkFileSize from './size-checker';
  
  // get arguments
  const opt = create([
    ['',  'files=ARG', 'target files for lint'],
    ['',  'limit=ARG', 'limit size'],
    ['h', 'help',      'display this help'],
  ]).bindHelp().parseSystem();
  
  const targetFiles = opt.options.files;
  const limitSize   = opt.options.limit;
  
  glob(targetFiles, (err, files) => {
    const promises = [];
  
    for (let file of files) {
      promises.push(checkFileSize(file, limitSize));
    }
  
    Promise.all(promises)
      .then(result => console.log('finish!'))
      .catch(err => console.error(`something error, ${err}`));
  });
  
new_contents: #!/usr/bin/env node
  
  /**
   * @description File size checker.
   * @author sota1235
   */
  
  "use strict";
  
  import { create } from 'node-getopt';
  import glob from 'glob';
  import checkFileSize from './size-checker';
  
  // get arguments
  const opt = create([
    ['',  'files=ARG', 'target files for lint'],
    ['',  'limit=ARG', 'limit size'],
    ['h', 'help',      'display this help'],
  ]).bindHelp().parseSystem();
  
  const targetFiles = opt.options.files;
  const limitSize   = opt.options.limit;
  
  glob(targetFiles, (err, files) => {
    const promises = [];
  
    for (let file of files) {
      promises.push(checkFileSize(file, limitSize));
    }
  
    Promise.all(promises)
      .then(result => console.log('All check finished!'))
      .catch(err => {
        console.error(`something error, ${err}`)
        process.exit(1);
      });
  });
  
subject: fix error message and command status