错误（未定义的方法`start_with？'代表nil：NilClass）

Question

在构建项目时。

undefined method `start_with?' for nil:NilClass
    ActionView::Template::Error (undefined method `start_with?' for nil:NilClass):
     <meta name="viewport" content="width=device-width, initial-    scale=1">
    11:     <title><%= Shoppe.settings.site_title%></title>
    12:     <meta charset="UTF-8">
    13:     <%= stylesheet_link_tag 'application' %>
    14:     <%= javascript_include_tag 'application', 'data-turbolinks-track' => true %>
    15:     <%= csrf_meta_tags %>

Gemfile中的

source 'https://rubygems.org'
gem 'redcarpet'
gem 'faker'
gem 'thin'
gem 'shoppe', :path => 'lib/shoppe', :require => 'shoppe'
gem 'rails', '4.2.4'
gem 'mysql2', '~> 0.3.20'
gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.1.0'runtimes
gem 'jquery-rails'

gem 'turbolinks']
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0', group: :doc
group :development, :test dodebugger console
gem 'byebug'
end
group :development do
gem 'web-console', '~> 2.0'
gem 'spring'
end

我不知道修复此错误。