Inject Rails' channel paths in engine.

We were explicitly referencing Rails.root in ActionCable::Server::Configuration.initialize,
thereby coupling ourselves to Rails.

Instead add `app/channels` to Rails' app paths and assign the existent files
to `channel_paths`.

Users can still append to those load paths with `<<` and `push` in `config/application.rb`.

This means we can remove the custom `Dir` lookup in `channel_paths` and the Rails
and root definitions in the tests.

2 files changed, 1 insertions, 17 deletions

diff --git a/actioncable/test/client_test.rb b/actioncable/test/client_test.rb
index 4ade9832e0..f2b090cc52 100644
--- a/actioncable/test/client_test.rb
+++ b/actioncable/test/client_test.rb
@@ -16,12 +16,8 @@ class ClientTest < ActionCable::TestCase
     ::Object.const_set(:ApplicationCable, Module.new)
     ::ApplicationCable.const_set(:Connection, Class.new(ActionCable::Connection::Base))
 
-    ::Object.const_set(:Rails, Module.new)
-    ::Rails.singleton_class.send(:define_method, :root) { Pathname.new(__dir__) }
-
     ActionCable.instance_variable_set(:@server, nil)
     server = ActionCable.server
-    server.config = ActionCable::Server::Configuration.new
     inner_logger = Logger.new(StringIO.new).tap { |l| l.level = Logger::UNKNOWN }
     server.config.logger = ActionCable::Connection::TaggedLoggerProxy.new(inner_logger, tags: [])
 
@@ -29,7 +25,7 @@ class ClientTest < ActionCable::TestCase
 
     # and now the "real" setup for our test:
     server.config.disable_request_forgery_protection = true
-    server.config.channel_load_paths = [File.expand_path('client', __dir__)]
+    server.config.channel_paths = [ File.expand_path('client/echo_channel.rb', __dir__) ]
 
     Thread.new { EventMachine.run } unless EventMachine.reactor_running?
     Thread.pass until EventMachine.reactor_running?
@@ -45,10 +41,6 @@ class ClientTest < ActionCable::TestCase
       ::Object.send(:remove_const, :ApplicationCable)
     rescue NameError
     end
-    begin
-      ::Object.send(:remove_const, :Rails)
-    rescue NameError
-    end
   end
 
   def with_puma_server(rack_app = ActionCable.server, port = 3099)
diff --git a/actioncable/test/subscription_adapter/common.rb b/actioncable/test/subscription_adapter/common.rb
index 361858784e..1b6f8c70bf 100644
--- a/actioncable/test/subscription_adapter/common.rb
+++ b/actioncable/test/subscription_adapter/common.rb
@@ -13,11 +13,7 @@ module CommonSubscriptionAdapterTest
     ::Object.const_set(:ApplicationCable, Module.new)
     ::ApplicationCable.const_set(:Connection, Class.new(ActionCable::Connection::Base))
 
-    ::Object.const_set(:Rails, Module.new)
-    ::Rails.singleton_class.send(:define_method, :root) { Pathname.new(__dir__) }
-
     server = ActionCable::Server::Base.new
-    server.config = ActionCable::Server::Configuration.new
     inner_logger = Logger.new(StringIO.new).tap { |l| l.level = Logger::UNKNOWN }
     server.config.logger = ActionCable::Connection::TaggedLoggerProxy.new(inner_logger, tags: [])
 
@@ -39,10 +35,6 @@ module CommonSubscriptionAdapterTest
       ::Object.send(:remove_const, :ApplicationCable)
     rescue NameError
     end
-    begin
-      ::Object.send(:remove_const, :Rails)
-    rescue NameError
-    end
   end