expose.js

var path = require('path')
var fs = require('fs')
var crypto = require('crypto')
var shasum = crypto.createHash('sha1')

module.exports = function (grunt) {
  'use strict'

  var _ = grunt.util._

  function generatesha1 (fileName) {
    var content = fs.readFileSync(fileName)

    shasum.update('blob ' + content.length + '\0', 'utf8')
    shasum.update(content)

    return shasum.digest('hex')
  }

  grunt.registerTask('expose', 'Expose available tasks as JSON object.', function (gruntFileName) {
    var cwd = process.cwd()
    gruntFileName = path.join(cwd, gruntFileName)
    var cacheFileName = path.join(cwd, '.sublime-grunt.cache')
    var sha1 = generatesha1(gruntFileName)

    var gruntSublimeCache = (grunt.file.exists(cacheFileName) && grunt.file.readJSON(cacheFileName)) || {}

    if (!gruntSublimeCache[gruntFileName] || gruntSublimeCache[gruntFileName].sha1 !== sha1) {
      var tasks = grunt.task._tasks

      _.each(tasks, function (value, key, list) {
        // We don't want to shouw or own task
        if (key === 'expose') {
          delete list[key]
        } else {
          // Filter away reservered words that are none-targets
          var targets = _.difference(Object.keys(grunt.config.getRaw(key) || {}), ['files', 'options', 'globals'])

          if (targets.length > 0) {
            list[key].targets = targets

            if (targets.length > 1) {
              _.each(targets, function (target) {
                var name = key + ':' + target

                list[name] = {
                  name: name,
                  info: 'Targets ' + name + '. ' + list[key].info || '',
                  meta: {
                    info: list[key].meta && list[key].meta.info
                  }
                }
              })
            }
          }
        }
      })

      gruntSublimeCache[gruntFileName] = gruntSublimeCache[gruntFileName] || {}
      gruntSublimeCache[gruntFileName].sha1 = sha1
      gruntSublimeCache[gruntFileName].tasks = tasks

      grunt.file.write(cacheFileName, JSON.stringify(gruntSublimeCache))
    }
  })
}