ArgumentError（Api::V1 的副本已从模块树中删除，但仍处于活动状态！）
ArgumentError (A copy of Api::V1 has been removed from the module tree but is still active!)
几天来我一直在为这个问题苦苦挣扎。我有一个正在为其构建一些 API 的应用程序，当第一次 运行 时，上述错误总是使我的应用程序崩溃。重新加载应用程序时错误消失，但它更烦人 none。以下是关于此错误的一些类似问题：
ArgumentError: A copy of ApplicationController has been removed from the module tree but is still active
这两个链接都没有解决我面临的问题。这是完整的堆栈跟踪：
ArgumentError (A copy of Api::V1 has been removed from the module tree but is still active!):
activesupport (5.1.4) lib/active_support/dependencies.rb:495:in `load_missing_constant'
activesupport (5.1.4) lib/active_support/dependencies.rb:202:in `const_missing'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:271:in `const_get'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:271:in `block in constantize'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:267:in `each'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:267:in `inject'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:267:in `constantize'
activesupport (5.1.4) lib/active_support/dependencies.rb:582:in `get'
activesupport (5.1.4) lib/active_support/dependencies.rb:613:in `constantize'
actionpack (5.1.4) lib/action_dispatch/http/request.rb:85:in `controller_class_for'
actionpack (5.1.4) lib/action_dispatch/http/parameters.rb:99:in `binary_params_for?'
actionpack (5.1.4) lib/action_dispatch/http/parameters.rb:90:in `set_binary_encoding'
actionpack (5.1.4) lib/action_dispatch/http/parameters.rb:67:in `path_parameters='
actionpack (5.1.4) lib/action_dispatch/journey/router.rb:48:in `block in serve'
actionpack (5.1.4) lib/action_dispatch/journey/router.rb:33:in `each'
actionpack (5.1.4) lib/action_dispatch/journey/router.rb:33:in `serve'
actionpack (5.1.4) lib/action_dispatch/routing/route_set.rb:834:in `call'
bullet (5.7.5) lib/bullet/rack.rb:14:in `call'
warden (1.2.7) lib/warden/manager.rb:36:in `block in call'
warden (1.2.7) lib/warden/manager.rb:35:in `catch'
warden (1.2.7) lib/warden/manager.rb:35:in `call'
rack (2.0.5) lib/rack/etag.rb:25:in `call'
rack (2.0.5) lib/rack/conditional_get.rb:25:in `call'
rack (2.0.5) lib/rack/head.rb:12:in `call'
rack (2.0.5) lib/rack/session/abstract/id.rb:232:in `context'
rack (2.0.5) lib/rack/session/abstract/id.rb:226:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/cookies.rb:613:in `call'
activerecord (5.1.4) lib/active_record/migration.rb:556:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/callbacks.rb:26:in `block in call'
activesupport (5.1.4) lib/active_support/callbacks.rb:97:in `run_callbacks'
actionpack (5.1.4) lib/action_dispatch/middleware/callbacks.rb:24:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/executor.rb:12:in `call'
airbrake (7.3.0) lib/airbrake/rack/middleware.rb:52:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/debug_exceptions.rb:59:in `call'
web-console (3.6.1) lib/web_console/middleware.rb:135:in `call_app'
web-console (3.6.1) lib/web_console/middleware.rb:30:in `block in call'
web-console (3.6.1) lib/web_console/middleware.rb:20:in `catch'
web-console (3.6.1) lib/web_console/middleware.rb:20:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
railties (5.1.4) lib/rails/rack/logger.rb:36:in `call_app'
railties (5.1.4) lib/rails/rack/logger.rb:24:in `block in call'
activesupport (5.1.4) lib/active_support/tagged_logging.rb:69:in `block in tagged'
activesupport (5.1.4) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (5.1.4) lib/active_support/tagged_logging.rb:69:in `tagged'
railties (5.1.4) lib/rails/rack/logger.rb:24:in `call'
sprockets-rails (3.2.1) lib/sprockets/rails/quiet_assets.rb:13:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/remote_ip.rb:79:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/request_id.rb:25:in `call'
rack (2.0.5) lib/rack/method_override.rb:22:in `call'
rack (2.0.5) lib/rack/runtime.rb:22:in `call'
activesupport (5.1.4) lib/active_support/cache/strategy/local_cache_middleware.rb:27:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/static.rb:125:in `call'
rack (2.0.5) lib/rack/sendfile.rb:111:in `call'
rack-mini-profiler (1.0.0) lib/mini_profiler/profiler.rb:285:in `call'
webpacker (3.4.3) lib/webpacker/dev_server_proxy.rb:18:in `perform_request'
rack-proxy (0.6.4) lib/rack/proxy.rb:57:in `call'
railties (5.1.4) lib/rails/engine.rb:522:in `call'
puma (3.11.4) lib/puma/configuration.rb:225:in `call'
puma (3.11.4) lib/puma/server.rb:632:in `handle_request'
puma (3.11.4) lib/puma/server.rb:446:in `process_client'
puma (3.11.4) lib/puma/server.rb:306:in `block in run'
puma (3.11.4) lib/puma/thread_pool.rb:120:in `block in spawn_thread'
如堆栈跟踪所示，这是应用程序与 ActiveSupport 的依赖性冲突。我建议使用 gem bootsnap. Bootsnap overrides ActiveSupport::Dependencies which is causing the issue in the first place. It also improves the app's load time which is actually what it is designed for. From Bootsnap 文档：
ActiveSupport::Dependencies.{autoloadable_module?,load_missing_constant,depend_on} are overridden to eliminate scans of ActiveSupport::Dependencies.autoload_paths.
几天来我一直在为这个问题苦苦挣扎。我有一个正在为其构建一些 API 的应用程序，当第一次 运行 时，上述错误总是使我的应用程序崩溃。重新加载应用程序时错误消失，但它更烦人 none。以下是关于此错误的一些类似问题：
ArgumentError: A copy of ApplicationController has been removed from the module tree but is still active
这两个链接都没有解决我面临的问题。这是完整的堆栈跟踪：
ArgumentError (A copy of Api::V1 has been removed from the module tree but is still active!):
activesupport (5.1.4) lib/active_support/dependencies.rb:495:in `load_missing_constant'
activesupport (5.1.4) lib/active_support/dependencies.rb:202:in `const_missing'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:271:in `const_get'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:271:in `block in constantize'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:267:in `each'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:267:in `inject'
activesupport (5.1.4) lib/active_support/inflector/methods.rb:267:in `constantize'
activesupport (5.1.4) lib/active_support/dependencies.rb:582:in `get'
activesupport (5.1.4) lib/active_support/dependencies.rb:613:in `constantize'
actionpack (5.1.4) lib/action_dispatch/http/request.rb:85:in `controller_class_for'
actionpack (5.1.4) lib/action_dispatch/http/parameters.rb:99:in `binary_params_for?'
actionpack (5.1.4) lib/action_dispatch/http/parameters.rb:90:in `set_binary_encoding'
actionpack (5.1.4) lib/action_dispatch/http/parameters.rb:67:in `path_parameters='
actionpack (5.1.4) lib/action_dispatch/journey/router.rb:48:in `block in serve'
actionpack (5.1.4) lib/action_dispatch/journey/router.rb:33:in `each'
actionpack (5.1.4) lib/action_dispatch/journey/router.rb:33:in `serve'
actionpack (5.1.4) lib/action_dispatch/routing/route_set.rb:834:in `call'
bullet (5.7.5) lib/bullet/rack.rb:14:in `call'
warden (1.2.7) lib/warden/manager.rb:36:in `block in call'
warden (1.2.7) lib/warden/manager.rb:35:in `catch'
warden (1.2.7) lib/warden/manager.rb:35:in `call'
rack (2.0.5) lib/rack/etag.rb:25:in `call'
rack (2.0.5) lib/rack/conditional_get.rb:25:in `call'
rack (2.0.5) lib/rack/head.rb:12:in `call'
rack (2.0.5) lib/rack/session/abstract/id.rb:232:in `context'
rack (2.0.5) lib/rack/session/abstract/id.rb:226:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/cookies.rb:613:in `call'
activerecord (5.1.4) lib/active_record/migration.rb:556:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/callbacks.rb:26:in `block in call'
activesupport (5.1.4) lib/active_support/callbacks.rb:97:in `run_callbacks'
actionpack (5.1.4) lib/action_dispatch/middleware/callbacks.rb:24:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/executor.rb:12:in `call'
airbrake (7.3.0) lib/airbrake/rack/middleware.rb:52:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/debug_exceptions.rb:59:in `call'
web-console (3.6.1) lib/web_console/middleware.rb:135:in `call_app'
web-console (3.6.1) lib/web_console/middleware.rb:30:in `block in call'
web-console (3.6.1) lib/web_console/middleware.rb:20:in `catch'
web-console (3.6.1) lib/web_console/middleware.rb:20:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/show_exceptions.rb:31:in `call'
railties (5.1.4) lib/rails/rack/logger.rb:36:in `call_app'
railties (5.1.4) lib/rails/rack/logger.rb:24:in `block in call'
activesupport (5.1.4) lib/active_support/tagged_logging.rb:69:in `block in tagged'
activesupport (5.1.4) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (5.1.4) lib/active_support/tagged_logging.rb:69:in `tagged'
railties (5.1.4) lib/rails/rack/logger.rb:24:in `call'
sprockets-rails (3.2.1) lib/sprockets/rails/quiet_assets.rb:13:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/remote_ip.rb:79:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/request_id.rb:25:in `call'
rack (2.0.5) lib/rack/method_override.rb:22:in `call'
rack (2.0.5) lib/rack/runtime.rb:22:in `call'
activesupport (5.1.4) lib/active_support/cache/strategy/local_cache_middleware.rb:27:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/executor.rb:12:in `call'
actionpack (5.1.4) lib/action_dispatch/middleware/static.rb:125:in `call'
rack (2.0.5) lib/rack/sendfile.rb:111:in `call'
rack-mini-profiler (1.0.0) lib/mini_profiler/profiler.rb:285:in `call'
webpacker (3.4.3) lib/webpacker/dev_server_proxy.rb:18:in `perform_request'
rack-proxy (0.6.4) lib/rack/proxy.rb:57:in `call'
railties (5.1.4) lib/rails/engine.rb:522:in `call'
puma (3.11.4) lib/puma/configuration.rb:225:in `call'
puma (3.11.4) lib/puma/server.rb:632:in `handle_request'
puma (3.11.4) lib/puma/server.rb:446:in `process_client'
puma (3.11.4) lib/puma/server.rb:306:in `block in run'
puma (3.11.4) lib/puma/thread_pool.rb:120:in `block in spawn_thread'
如堆栈跟踪所示，这是应用程序与 ActiveSupport 的依赖性冲突。我建议使用 gem bootsnap. Bootsnap overrides ActiveSupport::Dependencies which is causing the issue in the first place. It also improves the app's load time which is actually what it is designed for. From Bootsnap 文档：
ActiveSupport::Dependencies.{autoloadable_module?,load_missing_constant,depend_on} are overridden to eliminate scans of ActiveSupport::Dependencies.autoload_paths.