Ruby on rails 亚马尔；Rails：没有从nil到integer的隐式转换

我正在创建一个带有三个助手方法的Rails引擎。一个加载YAML配置文件，另一个确定YAML配置文件中是否存在选项，如果存在，则返回YAML配置选项的值。否则，它将返回Rails应用程序名和字符串

'：chat'

：

def config_file
  YAML.load_file(Rails.root.join('config', 'kouventa.yml'))
end

# This helper gets the name of the Rails app you're in.
# It also appends a :chat to it.
def app_name
  yaml = config_file
  name = Rails.application.class.to_s.split('::').first

  if yaml[:app][:name] == true
    yaml[:app][:name]
  else
    "#{name.uncapitalize}:chat"
  end
end

问题是，如果我在ERB模板中包含

，它会引发以下错误：

没有从nil到integer的隐式转换

以下是完整的跟踪：

/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/psych.rb:297:in `initialize'
/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/psych.rb:297:in `open'
/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/psych.rb:297:in `load_file'
/Users/chris/src/railssrc/kouventa/app/helpers/kouventa/application_helper.rb:4:in `config_file'
/Users/chris/src/railssrc/kouventa/app/helpers/kouventa/application_helper.rb:10:in `app_name'
/Users/chris/src/railssrc/kouventa/app/views/layouts/kouventa/application.html.erb:16:in `___sers_chris_src_railssrc_kouventa_app_views_layouts_kouventa_application_html_erb___3103356657825490294_70127840047660'
actionpack (3.2.11) lib/action_view/template.rb:145:in `block in render'
activesupport (3.2.11) lib/active_support/notifications.rb:125:in `instrument'
actionpack (3.2.11) lib/action_view/template.rb:143:in `render'
actionpack (3.2.11) lib/action_view/renderer/template_renderer.rb:59:in `render_with_layout'
actionpack (3.2.11) lib/action_view/renderer/template_renderer.rb:45:in `render_template'
actionpack (3.2.11) lib/action_view/renderer/template_renderer.rb:18:in `render'
actionpack (3.2.11) lib/action_view/renderer/renderer.rb:36:in `render_template'
actionpack (3.2.11) lib/action_view/renderer/renderer.rb:17:in `render'
actionpack (3.2.11) lib/abstract_controller/rendering.rb:110:in `_render_template'
actionpack (3.2.11) lib/action_controller/metal/streaming.rb:225:in `_render_template'
actionpack (3.2.11) lib/abstract_controller/rendering.rb:103:in `render_to_body'
actionpack (3.2.11) lib/action_controller/metal/renderers.rb:28:in `render_to_body'
actionpack (3.2.11) lib/action_controller/metal/compatibility.rb:50:in `render_to_body'
actionpack (3.2.11) lib/abstract_controller/rendering.rb:88:in `render'
actionpack (3.2.11) lib/action_controller/metal/rendering.rb:16:in `render'
actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:40:in `block (2 levels) in render'
activesupport (3.2.11) lib/active_support/core_ext/benchmark.rb:5:in `block in ms'
/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/benchmark.rb:295:in `realtime'
activesupport (3.2.11) lib/active_support/core_ext/benchmark.rb:5:in `ms'
actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:40:in `block in render'
actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:83:in `cleanup_view_runtime'
activerecord (3.2.11) lib/active_record/railties/controller_runtime.rb:24:in `cleanup_view_runtime'
actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:39:in `render'
actionpack (3.2.11) lib/action_controller/metal/implicit_render.rb:10:in `default_render'
actionpack (3.2.11) lib/action_controller/metal/implicit_render.rb:5:in `send_action'
actionpack (3.2.11) lib/abstract_controller/base.rb:167:in `process_action'
actionpack (3.2.11) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (3.2.11) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (3.2.11) lib/active_support/callbacks.rb:403:in `_run__1576663026866565057__process_action__3352794237780824881__callbacks'
activesupport (3.2.11) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.11) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
activesupport (3.2.11) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.11) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.2.11) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.2.11) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.11) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.11) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.11) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.2.11) lib/action_controller/metal/params_wrapper.rb:207:in `process_action'
activerecord (3.2.11) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (3.2.11) lib/abstract_controller/base.rb:121:in `process'
actionpack (3.2.11) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.11) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.11) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.11) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:73:in `call'
actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:36:in `call'
journey (1.0.4) lib/journey/router.rb:68:in `block in call'
journey (1.0.4) lib/journey/router.rb:56:in `each'
journey (1.0.4) lib/journey/router.rb:56:in `call'
actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:601:in `call'
railties (3.2.11) lib/rails/engine.rb:479:in `call'
railties (3.2.11) lib/rails/railtie/configurable.rb:30:in `method_missing'
journey (1.0.4) lib/journey/router.rb:68:in `block in call'
journey (1.0.4) lib/journey/router.rb:56:in `each'
journey (1.0.4) lib/journey/router.rb:56:in `call'
actionpack (3.2.11) lib/action_dispatch/routing/route_set.rb:601:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.4) lib/rack/etag.rb:23:in `call'
rack (1.4.4) lib/rack/conditionalget.rb:25:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.4) lib/rack/session/abstract/id.rb:210:in `context'
rack (1.4.4) lib/rack/session/abstract/id.rb:205:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/cookies.rb:341:in `call'
activerecord (3.2.11) lib/active_record/query_cache.rb:64:in `call'
activerecord (3.2.11) lib/active_record/connection_adapters/abstract/connection_pool.rb:479:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.11) lib/active_support/callbacks.rb:405:in `_run__2096171487662296236__call__865153784229083501__callbacks'
activesupport (3.2.11) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.11) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.11) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.11) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.11) lib/rails/rack/logger.rb:32:in `call_app'
railties (3.2.11) lib/rails/rack/logger.rb:16:in `block in call'
activesupport (3.2.11) lib/active_support/tagged_logging.rb:22:in `tagged'
railties (3.2.11) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.4) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.4) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.11) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.4) lib/rack/lock.rb:15:in `call'
actionpack (3.2.11) lib/action_dispatch/middleware/static.rb:62:in `call'
railties (3.2.11) lib/rails/engine.rb:479:in `call'
railties (3.2.11) lib/rails/application.rb:223:in `call'
railties (3.2.11) lib/rails/railtie/configurable.rb:30:in `method_missing'
unicorn (4.5.0) lib/unicorn/http_server.rb:552:in `process_client'
unicorn (4.5.0) lib/unicorn/http_server.rb:628:in `worker_loop'
unicorn (4.5.0) lib/unicorn/http_server.rb:500:in `spawn_missing_workers'
unicorn (4.5.0) lib/unicorn/http_server.rb:142:in `start'
unicorn (4.5.0) bin/unicorn_rails:209:in `<top (required)>'
/Users/chris/.rvm/gems/ruby-1.9.3-p194/bin/unicorn_rails:19:in `load'
/Users/chris/.rvm/gems/ruby-1.9.3-p194/bin/unicorn_rails:19:in `<main>'
/Users/chris/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `eval'
/Users/chris/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `<main>'

/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/psych.rb:297:in'initialize'
/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/psych.rb:297:in'open'
/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/psych.rb:297:in'load_file'
/Users/chris/src/railssrc/kouventa/app/helpers/kouventa/application\u helper.rb:4:在“配置文件”中
/Users/chris/src/railssrc/kouventa/app/helpers/kouventa/application\u helper.rb:10:in'app\u name'
/Users/chris/src/railssrc/kouventa/app/views/layouts/kouventa/application.html.erb:16:in`` uuuuuuu sers\u chris\u src\railssrc\u kouventa\u app\u view\u kouventa\u application\u html\u erb\uu3356657825490294\u 70127840047660'
actionpack（3.2.11）lib/action_view/template.rb:145:在“渲染中的块”中
activesupport（3.2.11）lib/active_support/notifications.rb:125:in'instrument'
actionpack（3.2.11）lib/action_view/template.rb:143:in'render'
actionpack（3.2.11）lib/action\u view/renderer/template\u renderer.rb:59:in'render\u with\u layout'
actionpack（3.2.11）lib/action_view/renderer/template_renderer.rb:45:in'render_template'
actionpack（3.2.11）lib/action_view/renderer/template_renderer.rb:18:in'render'
actionpack（3.2.11）lib/action_view/renderer/renderer.rb:36:in'render_template'
actionpack（3.2.11）lib/action_view/renderer/renderer.rb:17:in'render'
actionpack（3.2.11）lib/abstract\u controller/rendering.rb:110:在`\u render\u模板'中
actionpack（3.2.11）lib/action\u controller/metal/streaming.rb:225:在“渲染”模板中
actionpack（3.2.11）lib/abstract\u controller/rendering.rb:103:in'render\u to\u body'
actionpack（3.2.11）lib/action_controller/metal/renderers.rb:28:in“render_to_body”
actionpack（3.2.11）lib/action\u controller/metal/compatibility.rb:50:in'render\u to\u body'
actionpack（3.2.11）lib/abstract_controller/rendering.rb:88:in'render'
actionpack（3.2.11）lib/action_controller/metal/rendering.rb:16:in'render'
actionpack（3.2.11）lib/action_controller/metal/instrumentation.rb:40:in“渲染中的块（2层）”中
activesupport（3.2.11）lib/active\u support/core\u ext/benchmark.rb:5:in'block in ms'
/Users/chris/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/1.9.1/benchmark.rb:295:in'realtime'
activesupport（3.2.11）lib/active\u support/core\u ext/benchmark.rb:5:in`ms'
actionpack（3.2.11）lib/action_controller/metal/instrumentation.rb:40:在“渲染中的块”中
actionpack（3.2.11）lib/action\u controller/metal/instrumentation.rb:83:in'cleanup\u view\u runtime'
activerecord（3.2.11）lib/active_record/railties/controller_runtime.rb:24:in'cleanup_view_runtime'
actionpack（3.2.11）lib/action_controller/metal/instrumentation.rb:39:in'render'
actionpack（3.2.11）lib/action\u controller/metal/implicit\u render.rb:10:in'default\u render'
actionpack（3.2.11）lib/action\u controller/metal/implicit\u render.rb:5:in'send\u action'
actionpack（3.2.11）lib/abstract\u controller/base.rb:167:in'process\u action'
actionpack（3.2.11）lib/action\u controller/metal/rendering.rb:10:in'process\u action'
actionpack（3.2.11）lib/abstract\u controller/callbacks.rb:18:in‘block in process\u action’
activesupport（3.2.11）lib/active\u support/callbacks.rb:403:in`“u run\u 1576663026866565057\u process\u action\u 335279423778084881\u callbacks”
activesupport（3.2.11）lib/active\u support/callbacks.rb:405:in`\uu run\u callback'
activesupport（3.2.11）lib/active\u support/callbacks.rb:385:in``运行\进程\操作\回调'
activesupport（3.2.11）lib/active\u support/callbacks.rb:81:in'run\u callbacks'
actionpack（3.2.11）lib/abstract\u controller/callbacks.rb:17:in'process\u action'
actionpack（3.2.11）lib/action\u controller/metal/rescue.rb:29:in'process\u action'
actionpack（3.2.11）lib/action\u controller/metal/instrumentation.rb:30:in‘block in process\u action’中
activesupport（3.2.11）lib/active_support/notifications.rb:123:in'block in instrument'
activesupport（3.2.11）lib/active_support/notifications/instrumenter.rb:20:in'instrument'
activesupport（3.2.11）lib/active_support/notifications.rb:123:in'instrument'
actionpack（3.2.11）lib/action\u controller/metal/instrumentation.rb:29:in'process\u action'
actionpack（3.2.11）lib/action_controller/metal/params_wrapper.rb:207:在“进程_操作”中
activerecord（3.2.11）lib/active_record/railties/controller_runtime.rb:18:in'process_action'
actionpack（3.2.11）lib/abstract_controller/base.rb:121:正在进行中
actionpack（3.2.11）lib/abstract_controller/rendering.rb:45:in'process'
actionpack（3.2.11）lib/action_controller/metal.rb:203:in'dispatch'
actionpack（3.2.11）lib/action\u controller/metal/rack\u delegation.rb:14:in'dispatch'
actionpack（3.2.11）lib/action_controller/metal.rb:246:in“block in action”
actionpack（3.2.11）lib/action\u dispatch/routing/route\u set.rb:73:in'call'
actionpack（3.2.11）lib/action_dispatch/routing/route_set.rb:73:in'dispatch'
actionpack（3.2.11）lib/action\u dispatch/routing/route\u set.rb:36:in'call'
旅程（1.0.4）lib/travely/router.rb:68:in“呼叫阻塞”
旅程（1.0.4）lib/travely/router.rb:56:in'each'
旅程（1.0.4）lib/travely/router.rb:56:in'call'
actionpack（3.2.11）lib/action_dispatch/routing/route_set.rb:601:in'call'
railties（3.2.11）lib/rails/engine.rb:479:in'call'
railties（3.2.11）lib/rails/railtie/configurable.rb:30:in'method_missing'
旅程（1.0.4）lib/travely/router.rb:68:in“呼叫阻塞”
旅程（1.0.4）lib/travely/router.rb:56:in'each'
旅程（1.0.4）lib/travely/router.rb:56:in'call'
actionpack（3.2.11）lib/action_dispatch/routing/route_set.rb:601:in'call'
actionpack（3.2.11）lib/action_dispatch/mid