title: when I use 'jekyll new <someSite>, it complain of missing folder when I `bundle exec jekyll serve`
body: <p>I want to create a website from scratch using Jekyll. I use this command: `jekyll new mysite'. And it spit out this:</p>
  
  <pre><code> repo&gt; jekyll new mysite
  Running bundle install in /Users/johntowery/repo/kbsite... 
    Bundler: Fetching gem metadata from https://rubygems.org/...........
    Bundler: Fetching gem metadata from https://rubygems.org/.
    Bundler: Resolving dependencies...
    Bundler: Using public_suffix 4.0.1
    Bundler: Using addressable 2.7.0
    Bundler: Using bundler 2.0.2
    Bundler: Using colorator 1.1.0
    Bundler: Using concurrent-ruby 1.1.5
    Bundler: Using eventmachine 1.2.7
    Bundler: Using http_parser.rb 0.6.0
    Bundler: Using em-websocket 0.5.1
    Bundler: Using ffi 1.11.1
    Bundler: Using forwardable-extended 2.6.0
    Bundler: Using i18n 1.6.0
    Bundler: Using sassc 2.2.0
    Bundler: Using jekyll-sass-converter 2.0.0
    Bundler: Using rb-fsevent 0.10.3
    Bundler: Using rb-inotify 0.10.0
    Bundler: Using ruby_dep 1.5.0
    Bundler: Using listen 3.1.5
    Bundler: Using jekyll-watch 2.2.1
    Bundler: Using kramdown 2.1.0
    Bundler: Using kramdown-parser-gfm 1.1.0
    Bundler: Using liquid 4.0.3
    Bundler: Using mercenary 0.3.6
    Bundler: Using pathutil 0.16.2
    Bundler: Using rouge 3.10.0
    Bundler: Using safe_yaml 1.0.5
    Bundler: Using unicode-display_width 1.6.0
    Bundler: Using terminal-table 1.8.0
    Bundler: Using jekyll 4.0.0
    Bundler: Using jekyll-feed 0.12.1
    Bundler: Using jekyll-seo-tag 2.6.1
    Bundler: Using minima 2.5.1
    Bundler: Bundle complete! 6 Gemfile dependencies, 31 gems now installed.
    Bundler: Use `bundle info [gemname]` to see where a bundled gem is installed.
  New jekyll site installed in /Users/johntowery/repo/mysite. 
  </code></pre>
  
  <p>It created some file and directories. I understnad that this new site use gem-based theme "Minima". </p>
  
  <pre><code>repo&gt; cd mysite 
  mysite&gt; ls
  404.html       Gemfile        Gemfile.lock   _config.yml    _posts         about.markdown index.markdown
  </code></pre>
  
  <p>So far so good. I do understand that _layout, _include, etc are already inside Minima theme so that's expected. I didn't add or change anything at this point. Now I run it using: <code>bundle execjekyll serve</code></p>
  
  <p>I get this.</p>
  
  <pre><code>mysite&gt; bundle exec jekyll serve
  Configuration file: /Users/johntowery/repo/kbsite/_config.yml
              Source: /Users/johntowery/repo/kbsite
         Destination: /Users/johntowery/repo/kbsite/_site
   Incremental build: disabled. Enable with --incremental
        Generating... 
         Jekyll Feed: Generating feed for posts
       Build Warning: Layout 'post' requested in _posts/2019-09-12-welcome-to-jekyll.markdown does not exist.
       Build Warning: Layout 'default' requested in 404.html does not exist.
       Build Warning: Layout 'page' requested in about.markdown does not exist.
       Build Warning: Layout 'home' requested in index.markdown does not exist.
                      done in 0.402 seconds.
   Auto-regeneration: enabled for '/Users/johntowery/repo/kbsite'
      Server address: http://127.0.0.1:4000/
    Server running... press ctrl-c to stop.
  </code></pre>
  
  <p>Why is it not recognizing that those "missing" Layout is in Minima gem?</p>
  
  <p>The <code>_config.yml</code> folder: (which was autogenerated by <code>jekyll new</code> and I didn't modify it.)</p>
  
  <pre><code># Welcome to Jekyll!
  #
  # This config file is meant for settings that affect your whole blog, values
  # which you are expected to set up once and rarely edit after that. If you find
  # yourself editing this file very often, consider using Jekyll's data files
  # feature for the data you need to update frequently.
  #
  # For technical reasons, this file is *NOT* reloaded automatically when you use
  # 'bundle exec jekyll serve'. If you change this file, please restart the server process.
  #
  # If you need help with YAML syntax, here are some quick references for you: 
  # https://learn-the-web.algonquindesign.ca/topics/markdown-yaml-cheat-sheet/#yaml
  # https://learnxinyminutes.com/docs/yaml/
  #
  # Site settings
  # These are used to personalize your new site. If you look in the HTML files,
  # you will see them accessed via {{ site.title }}, {{ site.email }}, and so on.
  # You can create any custom variable you would like, and they will be accessible
  # in the templates via {{ site.myvariable }}.
  
  title: Your awesome title
  email: your-email@example.com
  description: &gt;- # this means to ignore newlines until "baseurl:"
    Write an awesome description for your new site here. You can edit this
    line in _config.yml. It will appear in your document head meta (for
    Google search results) and in your feed.xml site description.
  baseurl: "" # the subpath of your site, e.g. /blog
  url: "" # the base hostname &amp; protocol for your site, e.g. http://example.com
  twitter_username: jekyllrb
  github_username:  jekyll
  
  # Build settings
  theme: minima
  plugins:
    - jekyll-feed
  
  # Exclude from processing.
  # The following items will not be processed, by default.
  # Any item listed under the `exclude:` key here will be automatically added to
  # the internal "default list".
  #
  # Excluded items can be processed by explicitly listing the directories or
  # their entries' file path in the `include:` list.
  #
  # exclude:
  #   - .sass-cache/
  #   - .jekyll-cache/
  #   - gemfiles/
  #   - Gemfile
  #   - Gemfile.lock
  #   - node_modules/
  #   - vendor/bundle/
  #   - vendor/cache/
  #   - vendor/gems/
  #   - vendor/ruby/
  </code></pre>
  
  <p>I understand that when creating new site using <code>jekyll new &lt;newstie&gt;</code>, it  will create all the basic files (scaffolding). And I do know that some folders are not created because it is already in the theme gem (Minima). And I do know that you only need to create the folder (_layouts, _includes, or _sass, etc etc) if you wanted to override the 'default'. I knew that. But I expect the <code>jekyll new &lt;sitename&gt;</code> create the essential and be able to <code>bundle exec jekyll serve</code> successfully. But it isn't. It is not recognizing that those 'missing' folder is in Minima gem. Why is it not recognizing it?  What's the point of Theme gems if Jekyll don't recognize the folder in the gem?</p>
  
  <p>Is there something missing?</p>
  
  <p>Im using:</p>
  
  <ul>
  <li>macOS Mojave (10.14.6 (18G95))</li>
  <li>ruby 2.6.4p104</li>
  <li>Bundler version 2.0.2</li>
  <li>jekyll 4.0.0</li>
  </ul>
  
  <p>thanks</p>