Merge pull request #27416 from voray/remove-throw-from-action-cable

ActionCable should not raise when a connection is already open

actioncable/app/assets/javascripts/action_cable/connection.coffee

@@ -23,7 +23,7 @@ class ActionCable.Connection
   open: =>
     if @isActive()
       ActionCable.log("Attempted to open WebSocket, but existing socket is #{@getState()}")
-      throw new Error("Existing connection must be closed before opening")
+      false
     else
       ActionCable.log("Opening WebSocket, current state is #{@getState()}, subprotocols: #{protocols}")
       @uninstallEventHandlers() if @webSocket?

actioncable/test/javascript/src/unit/consumer_test.coffee

@@ -2,8 +2,11 @@
 {consumerTest} = ActionCable.TestHelpers
 
 module "ActionCable.Consumer", ->
-  consumerTest "#connect", connect: false, ({consumer, server, done}) ->
-    server.on("connection", done)
+  consumerTest "#connect", connect: false, ({consumer, server, assert, done}) ->
+    server.on "connection", ->
+      assert.equal consumer.connect(), false
+      done()
+
     consumer.connect()
 
   consumerTest "#disconnect", ({consumer, client, done}) ->