Like UNIX Expect, but for Node.js.
Latest commit a0b8740 Jun 25, 2016 @piranna piranna v0.6.1

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Node.js - suppose

Have you ever heard of the command line program expect? Basically, expect allows you to automate command line programs. suppose is a programmable Node.js module that allows the same behavior.


From the expect wikipedia page, you can see many examples of expect scripts automating tasks such as telnet or ftp sessions. Now you can easily write Node.js scripts to do the same. This may be most beneficial during testing.


npm install suppose


Automate the command npm init, which initializes a new npm module.

var suppose = require('suppose')
  , fs = require('fs')
  , assert = require('assert')

fs.writeFileSync('/tmp/awesome/', 'READ IT')
// debug is an optional writeable output stream
suppose('npm', ['init'], {debug: fs.createWriteStream('/tmp/debug.txt')})
  .when(/name\: \([\w|\-]+\)[\s]*/).respond('awesome_package\n')
  .when('version: (1.0.0) ').respond('0.0.1\n')
  // response can also be the second argument to .when
  .when('description: ', "It's an awesome package man!\n")
  .when('entry point: (index.js) ').respond("\n")
  .when('test command: ').respond('npm test\n')
  .when('git repository: ').respond("\n")
  .when('keywords: ').respond('awesome, cool\n')
  .when('author: ').respond('JP Richardson\n')
  .when('license: (ISC) ').respond('MIT\n')
  .when('ok? (yes) ' ).respond('yes\n')
.on('error', function(err){
  var packageFile = '/tmp/awesome/package.json';
  fs.readFile(packageFile, function(err, data){
    var packageObj = JSON.parse(data.toString());
    console.log(; //'awesome_package'

.respond() may be called any number of times after .when(). Each response will be sent in the order defined when the condition matches. Once all conditions and responses are defined, call .end() to begin execution.



(MIT License)

Copyright 2012-2013, JP Richardson