Extract init command from probot/probot#139

h/t @boneskull

.gitignore

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+node_modules

LICENSE

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+ISC License
+
+Copyright (c) 2017, Brandon Keepers
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

bin/create-probot-plugin.js

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+#!/usr/bin/env node
+
+'use strict';
+
+const path = require('path');
+const inquirer = require('inquirer');
+const program = require('commander');
+const {scaffold} = require('egad');
+const kebabCase = require('lodash.kebabcase');
+const chalk = require('chalk');
+const stringifyAuthor = require('stringify-author');
+const {guessEmail, guessAuthor, guessGitHubUsername} = require('conjecture');
+
+const PLUGIN_REPO_URL = 'https://github.com/probot/plugin-template.git';
+
+program
+  .usage('[options] [destination]')
+  .option('-p, --pkgname <package-name>', 'Plugin package name')
+  .option('-d, --desc "<description>"',
+    'Plugin description (contain in quotes)')
+  .option('-a, --author "<full-name>"',
+    'Plugin author name (contain in quotes)')
+  .option('-e, --email <email>', 'Plugin author email address')
+  .option('-h, --homepage <homepage>', 'Plugin author\'s homepage')
+  .option('-u, --user <username>', 'GitHub username or org (repo owner)')
+  .option('-r, --repo <repo-name>', 'Plugin repo name')
+  .option('--overwrite', 'Overwrite existing files', false)
+  .option('--template <template-url>', 'URL of custom plugin template',
+    PLUGIN_REPO_URL)
+  .parse(process.argv);
+
+const destination = program.args.length ?
+  path.resolve(process.cwd(), program.args.shift()) :
+  process.cwd();
+
+const prompts = [
+  {
+    type: 'input',
+    name: 'name',
+    default(answers) {
+      return answers.repo || kebabCase(path.basename(destination));
+    },
+    message: 'Plugin\'s package name:',
+    when: !program.pkgname
+  },
+  {
+    type: 'input',
+    name: 'desc',
+    default() {
+      return 'A Probot plugin';
+    },
+    message: 'Description of plugin:',
+    when: !program.desc
+  },
+  {
+    type: 'input',
+    name: 'author',
+    default() {
+      return guessAuthor();
+    },
+    message: 'Plugin author\'s full name:',
+    when: !program.author
+  },
+  {
+    type: 'input',
+    name: 'email',
+    default() {
+      return guessEmail();
+    },
+    message: 'Plugin author\'s email address:',
+    when: !program.email
+  },
+  {
+    type: 'input',
+    name: 'homepage',
+    message: 'Plugin author\'s homepage:',
+    when: !program.homepage
+  },
+  {
+    type: 'input',
+    name: 'owner',
+    default(answers) {
+      return guessGitHubUsername(answers.email);
+    },
+    message: 'Plugin\'s GitHub user or org name:',
+    when: !program.user
+  },
+  {
+    type: 'input',
+    name: 'repo',
+    default(answers) {
+      return answers.pkgname || kebabCase(path.basename(destination));
+    },
+    message: 'Plugin\'s repo name:',
+    when: !program.repo
+  }
+];
+
+console.log(chalk.blue('Let\'s create a Probot plugin!'));
+
+inquirer.prompt(prompts)
+  .then(answers => {
+    answers.author = stringifyAuthor({
+      name: answers.author,
+      email: answers.email,
+      url: answers.homepage
+    });
+    return scaffold(program.template, destination, answers, {
+      overwrite: Boolean(program.overwrite)
+    });
+  })
+  .then(results => {
+    results.forEach(fileinfo => {
+      console.log(`${fileinfo.skipped ? chalk.yellow('skipped existing file') :
+        chalk.green('created file')}: ${fileinfo.path}`);
+    });
+    console.log(chalk.blue('Done!'));
+  });