Heroku 推送失败：“未定义的方法”

Question

嘿，我在将我的 rails 项目推送到 heroku 时遇到了一些问题，我收到以下错误：

remote:        Running: rake assets:precompile
remote:        I, [2015-07-24T19:05:36.903629 #973]  INFO -- : Writing /tmp/build_9e450c140b29b08f655c356ad7f8fe81/public/assets/application-3dba84f3550d057a7ebd21940bb94ece39b0ea686486aaaf4c32bb2fda950496.js
remote:        rake aborted!
remote:        NoMethodError: undefined method `[]' for nil:NilClass
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/sass_processor.rb:266:in `sprockets_context'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/sass_processor.rb:112:in `asset_path'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/sass_processor.rb:188:in `font_path'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:140:in `_perform'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/node.rb:50:in `perform'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:402:in `visit_return'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:36:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `block in with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:115:in `with_frame'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:8:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:248:in `block (3 levels) in perform_sass_fn'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:248:in `each'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:248:in `block (2 levels) in perform_sass_fn'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:247:in `catch'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:247:in `block in perform_sass_fn'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:84:in `perform_arguments'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:244:in `perform_sass_fn'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/funcall.rb:131:in `_perform'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/node.rb:50:in `perform'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/operation.rb:64:in `_perform'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/script/tree/node.rb:50:in `perform'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:468:in `visit_variable'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:36:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `block in with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:115:in `with_frame'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:325:in `map'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:88:in `block in with_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:115:in `with_frame'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:88:in `with_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:322:in `visit_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:36:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `block in with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:115:in `with_frame'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:325:in `block (2 levels) in visit_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:325:in `map'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:325:in `block in visit_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:88:in `block in with_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:115:in `with_frame'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:88:in `with_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:322:in `visit_import'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:36:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `block in visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `block in with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:115:in `with_frame'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/stack.rb:79:in `with_base'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:158:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:52:in `block in visit_children'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:52:in `map'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:52:in `visit_children'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:167:in `block in visit_children'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:179:in `with_environment'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:166:in `visit_children'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:36:in `block in visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:186:in `visit_root'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/base.rb:36:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:157:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/visitors/perform.rb:8:in `visit'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/root_node.rb:36:in `css_tree'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/tree/root_node.rb:20:in `render'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sass-3.4.16/lib/sass/engine.rb:278:in `render'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/sass_compressor.rb:48:in `call'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/sass_compressor.rb:28:in `call'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:75:in `call_processor'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:56:in `reverse_each'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/processor_utils.rb:56:in `call_processors'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:86:in `load_asset_by_uri'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:45:in `block in load'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:155:in `fetch_asset_from_dependency_cache'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/loader.rb:38:in `load'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:20:in `block in initialize'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:47:in `yield'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/cached_environment.rb:47:in `load'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/base.rb:63:in `find_asset'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/base.rb:70:in `find_all_linked_assets'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/manifest.rb:138:in `block in find'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:114:in `block (2 levels) in logical_paths'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:223:in `block in stat_tree'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:207:in `block in stat_directory'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:204:in `each'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:204:in `stat_directory'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/path_utils.rb:222:in `stat_tree'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:105:in `each'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:105:in `block in logical_paths'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:104:in `each'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/legacy.rb:104:in `logical_paths'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/manifest.rb:136:in `find'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/sprockets/manifest.rb:162:in `compile'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-rails-2.3.2/lib/sprockets/rails/task.rb:70:in `block (3 levels) in define'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-3.2.0/lib/rake/sprocketstask.rb:147:in `with_logger'
remote:        /tmp/build_9e450c140b29b08f655c356ad7f8fe81/vendor/bundle/ruby/2.0.0/gems/sprockets-rails-2.3.2/lib/sprockets/rails/task.rb:69:in `block (2 levels) in define'
remote:        Tasks: TOP => assets:precompile
remote:        (See full trace by running task with --trace)
remote:  !
remote:  !     Precompiling assets failed.
remote:  !
remote: 

Tt 好像跟 js 文件有关。如果有帮助，我正在使用 cloud 9。

我的宝石文件：

source 'https://rubygems.org'

gem 'rails',        '4.2.2'
gem 'bcrypt',               '3.1.7'
gem 'bootstrap-sass',       '3.2.0.0'
gem 'sass-rails',   '5.0.2'
gem 'uglifier',     '2.5.3'
gem 'coffee-rails', '4.1.0'
gem 'jquery-rails', '4.0.3'
gem 'turbolinks',   '2.3.0'
gem 'jbuilder',     '2.2.3'
gem 'sdoc',         '0.4.0', group: :doc


group :development, :test do
  gem 'sqlite3',     '1.3.9'
  gem 'byebug',      '3.4.0'
  gem 'web-console', '2.0.0.beta3'
  gem 'spring',      '1.1.3'
end

group :test do
  gem 'minitest-reporters', '1.0.5'
  gem 'mini_backtrace',     '0.1.3'
  gem 'guard-minitest',     '2.3.1'
end

group :production do
  gem 'pg',             '0.17.1'
  gem 'rails_12factor', '0.0.2'
end

我的 application.js 文件：

// This is a manifest file that'll be compiled into application.js, which will include all the files
// listed below.
//
// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
// or any plugin's vendor/assets/javascripts directory can be referenced here using a relative path.
//
// It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
// compiled file.
//
// Read Sprockets README (https://github.com/rails/sprockets#sprockets-directives) for details
// about supported directives.
//
//= require jquery
//= require jquery_ujs
//= require bootstrap
//= require turbolinks
//= require_tree .

我之前在尝试推送到 heroku 时遇到了数据库问题，如果相关，我将 database.yml 文件更改为以下内容：

development:
  adapter: sqlite3
  database: db/development.sqlite3
  pool: 5
  timeout: 5000

test:
  adapter: sqlite3
  database: db/test.sqlite3
  pool: 5
  timeout: 5000

production:
  adapter: postgresql
  database: treebook
  pool: 5
  timeout: 5000

任何帮助将不胜感激，因为过去几天我一直无法解决这个问题。

项目的 github 仓库：https://github.com/Ghrehh/sitenew

编辑：

I, [2015-07-25T09:07:44.231727 #10217]  INFO -- : Writing /home/ubuntu/workspace/sitenew/public/assets/application-3dba84f3550d057a7ebd21940bb94ece39b0ea686486aaaf4c32bb2fda950496.js
rake aborted!
NoMethodError: undefined method `[]' for nil:NilClass
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/usr/local/rvm/gems/ruby-2.2.1/gems/sprockets-3.2.0/lib/sprockets/sass_processor.rb:188:in `font_path'
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Answer 1

链接到我的 CSS 文件中不存在的文件，愚蠢的错误。不要盲目复制粘贴以前项目的文件！