Command execution time

index.js

const cp = require('child_process')

const results = []
for (let i = 0; i < 10; i++) {
  const result = cp.execSync('yarn --cwd app build')
  const resultString = result.toString()
  const timeMatch = resultString.match(/\d\d\.\d\ds\./)
  if (timeMatch === null) {
    throw new Error('missing time result')
  }
  const time = parseFloat(timeMatch[0].replace('s.', ''))
  console.log(i, 'Time:', time);
  results.push(time)
}

const sum = results.reduce((sum, value) => sum + value, 0)

console.log('Avg:', (sum/results.length).toFixed(2), 'Max:', Math.max(...results), 'Min:', Math.min(...results))