Find files changed in git commits with message matching a pattern

git-message-filtered-files-changed.js

'use strict'

const repo = require('simple-git')(__dirname)
const rgx = /this|that/i
const start = (new Date('2014-12-29 00:00:00 -0500')).valueOf()
const sinceStart = (c) => (new Date(c.date)).valueOf() > start
const fileMap = {}

repo.log([], async (err, d) => {
  const commits = d.all.filter((c) => c.message.match(rgx) && sinceStart(c))

  await Promise.all(commits.map((c) => new Promise((resolve, reject) => {
    const cmd = ['diff-tree', '--no-commit-id', '--name-only', '-r', c.hash]
     repo.raw(cmd, (err, result) => {
       if (err) reject(err)
       result.split('\n').forEach((f) => { if (f) fileMap[f] = true })
       resolve()
     })
  })))

  const map = ([k, v]) => `- ${k}\n  ${v.reverse().map((vv) => `${vv}`).join(`\n  `)}`
  const toPrint = Object.entries(fileMap).map(map).sort().join('\n\n')
  console.log(toPrint)
})