虽然我仍然为什么上述方法不工作不清，并欢迎任何反馈，一些研究之后，我发现的shelljs ，我能够用它来解决我的问题。由于shelljs可以Exec的外壳命令同步，我没有与回调在工作的时候我真的希望事情块：

Although I'm still unclear on why the method above is not working, and welcome any feedback, after a bit of research, I found shelljs, which I was able to use to solve my problem. Since shelljs can exec shell commands synchronously, I don't have to work with callbacks when I really want things to block:

module.exports = (grunt) ->
  shell = require 'shelljs'
  envvar = shell.exec('./bin/get_envvar.sh', {'silent':true}).output

  grunt.initConfig
    pkg: grunt.file.readJSON('package.json')

    env:
      dev:
        ENV_VAR: envvar

    simplemocha:
      options:
        timeout: 30000
        reporter: 'spec'
        compilers: 'coffee:coffee-script'
      all:
        src: ['Tests/**/*.coffee']

  grunt.registerTask 'test', ['env', 'simplemocha']

很多清洁呢！

参考文献：

• How我可以grunt.initConfig（）？
之前执行异步操作

• http://jaketrent.com/post/im$p$pssions-of-grunt/

• How can I perform an asynchronous operation before grunt.initConfig()?
• http://jaketrent.com/post/impressions-of-grunt/