grunt-init y/n question helper.

questions.json

[
  {
    "name": "yes",
    "message": "This question will default to yes (true).",
    "default": true
  },
  {
    "name": "no",
    "message": "This question will default to no (false).",
    "default": false
  }
]

template.js

'use strict';

// Basic template description.
exports.description = 'Foo.';

// Template-specific notes to be displayed before question prompts.
exports.notes = 'Blah blah blah.';

// The actual init template.
exports.template = function(grunt, init, done) {

  // Helper to create a "yes/no" question.
  function yn(o) {
    o = grunt.util._.defaults({}, o, {
      default: true,
      warning: 'You must answer [y]es or [n]o.',
    });
    var defaultYes = o.default === true || String(o.default).toLowerCase() === 'y' || String(o.default)[0] === 'Y';
    o.default = defaultYes ? 'Y/n' : 'y/N';
    o.sanitize = function(value, data, done) {
      data[o.name] = defaultYes ? /y/i.test(value) : !/n/i.test(value);
      done();
    };
    return o;
  }

  // Helper to process an array of "yes/no" questions.
  function yns(o) {
    return o.map(yn);
  }

  // Prompt for these values.
  init.process({}, yns(require('./questions.json')), function(err, props) {
    console.log(props);
    done();
  });

};