state_emitter.rb in ably-0.2.0

- old
+ new

@@ -1,10 +1,13 @@
 module Ably::Modules
   # StateEmitter module adds a set of generic state related methods to a class on the assumption that
   # the instance variable @state is used exclusively, the {Enum} STATE is defined prior to inclusion of this
   # module, and the class is an {EventEmitter}.  It then emits state changes.
   #
+  # It also ensures the EventEmitter is configured to retrict permitted events to the
+  # the available STATEs and :error.
+  #
   # @example
   #   class Connection
   #     include Ably::Modules::EventEmitter
   #     extend  Ably::Modules::Enum
   #     STATE = ruby_enum('STATE',
@@ -52,10 +55,16 @@
     end
     alias_method :change_state, :state=
 
     private
     def self.included(klass)
-      klass.configure_event_emitter coerce_into: Proc.new { |event| klass::STATE(event) }
+      klass.configure_event_emitter coerce_into: Proc.new { |event|
+        if event == :error
+          :error
+        else
+          klass::STATE(event)
+        end
+      }
 
       klass::STATE.each do |state_predicate|
         klass.instance_eval do
           define_method("#{state_predicate.to_sym}?") do
             state?(state_predicate)