ggit/src/changed-files.js

Local promise-returning git command wrappers

var la = require('lazy-ass')
var check = require('check-more-types')
var exec = require('./exec')
var log = require('debug')('ggit')
var _ = require('lodash')
var R = require('ramda')
var fileContentsInRepo = require('./file-contents')
la(
  check.fn(fileContentsInRepo),
  'missing file contents function',
  fileContentsInRepo
)
var read = require('fs').readFileSync
var Q = require('q')
var repoRoot = require('./repo-root')
var join = require('path').join

var modifications = {
  A: 'added',
  M: 'modified',
  C: 'copied',
  D: 'deleted'
}

var stdoutToGrouped = require('./parse-file-status')

function changedFiles (needContents) {
  var gitCommand = _.template(
    'git diff --name-status --diff-filter=<%= filter %>'
  )
  log('filter letters Added (A), Copied (C), Deleted (D), Modified (M)')

  var filter = R.keys(modifications).join('')
  var cmd = gitCommand({ filter: filter })
  log('changed files command', cmd)

  function addContents (grouped) {
    if (!needContents) {
      return grouped
    }

    return repoRoot()
      .then(function (repoPath) {
        log('repo root', repoPath)
        return repoPath
      })
      .then(function (repoPath) {
        var promise = Q.when(grouped)

        _.each(grouped, function (list) {
          la(
            check.array(list),
            'expected list of modifications',
            list,
            'in',
            grouped
          )
          list.forEach(function (info) {
            la(check.unemptyString(info.name), 'missing file name', info)
            info.filename = join(repoPath, info.name)
          })
        })

        _.each(grouped, function (list, modification) {
          log('fetching contents for modification', modification)
          la(modifications[modification], 'unknown modification', modification)

          if (modification === 'M') {
            // need both repo and local copy
            list.forEach(function (info) {
              info.after = read(info.filename, 'utf8')
              promise = promise
                .then(function () {
                  return fileContentsInRepo(info.name).catch(
                    function fileNotFound () {
                      // maybe the file was just added and then modified
                      // GIT thinks it is M, but there is no repo content yet
                      return ''
                    }
                  )
                })
                .then(function (contents) {
                  info.before = contents
                  return grouped
                })
            })
          } else if (modification === 'A') {
            // for added files, only grab file contents
            list.forEach(function (info) {
              info.after = read(info.filename, 'utf8')
            })
          } else if (modification === 'D') {
            list.forEach(function (info) {
              promise = promise
                .then(function () {
                  return fileContentsInRepo(info.name)
                })
                .then(function (contents) {
                  info.before = contents
                  return grouped
                })
            })
          }
        })

        return promise
      })
  }

  // another command that gives status especially for added files
  var secondCommand = 'git status --porcelain'

  return Q.all([exec.exec(cmd), exec.exec(secondCommand)])
    .spread(function (firstOutput, secondOutput) {
      log('first output')
      log(firstOutput)
      log('second output')
      log(secondOutput)
      return firstOutput + '\n' + secondOutput
    })
    .then(stdoutToGrouped)
    .then(R.tap(log))
    .then(addContents)
}

module.exports = changedFiles

if (!module.parent) {
  ;(function showChangedFiles () {
    var needContents = true
    changedFiles(needContents)
      .then(function (files) {
        console.log('changed files in the current repo')
        console.log(files)
      })
      .done()
  })()
}