Custom implementation of how to run UNIX commands through NodeJS

run-unix-command-with-nodejs.ts

import { exec } from 'child_process'

/**
 * Usage:
 * 
 * const stdout = await _`ls -la`;
 * 
 * or:
 * 
 * const flags = [
 *   "--oneline",
 *   "--decorate",
 *   "--color"
 * ];
 * 
 * const stdout = await _`git log ${flags}`;
*/

const _ = async (pieces: any, ...args: any): Promise<string> => {
  let cmd = pieces[0]
  let i = 0

  while (i < args.length) {
    const arg = Array.isArray(args[i]) ? args[i].join(' ') : args[i]

    cmd += arg + pieces[++i]
  }

  return new Promise((resolve, reject) => {
    const spawn = exec(cmd, (error, stdout, stderr) => {
      if (error || stderr) reject(error || stderr)

      resolve(stdout)
    })

    spawn.on('exit', (code, signal) => {
      code !== 0 &&
        reject(
          new Error(
            `Child process exited with exit code ${code}.${signal ? ` SIGNAL: ${signal}` : ''
            }`,
          ),
        )
    })
  })
}