flip eslint logs from rules-per-file pattern to files-per-rule pattern

eslint.log.js

const fs = require('fs')
const path = require('path')

const ESLING_LOG = path.join(__dirname, 'eslint.log')

const STATE = {
  EMPTY: 'EMPTY',
  FILE: 'FILE',
}

const BUGS = {}
const LOG_PATTERN = /^\s+([\S]*)\s+([\S]*).*\s+([\S]*)$/

let file = ''
let state = STATE.EMPTY

fs.readFileSync(ESLING_LOG, 'utf8')
  .split('\n')
  .forEach(line => {
    if (state === STATE.EMPTY) {
      if (line.startsWith('/')) {
        file = line
        state = STATE.FILE
        return
      }
    }

    if (state === STATE.FILE) {
      if (line === '') {
        file = ''
        state = STATE.EMPTY
        return
      }

      const match = line.match(LOG_PATTERN)
      if (match === null) {
        return
      }

      const [, position, level, type] = match
      const source = `${file}:${position}`
      const status = `${level}:${type}`

      if (status in BUGS) {
        BUGS[status].push(source)
      } else {
        BUGS[status] = [source]
      }
    }
  })

const logLines = []

Object.keys(BUGS)
  .sort()
  .forEach(status => {
    logLines.push(status)

    BUGS[status].sort().forEach(src => {
      logLines.push(`  ${src}`)
    })

    logLines.push('')
  })

fs.writeFileSync(ESLING_LOG, logLines.join('\n'))