Ensure idempotent publishing is automatically enabled in future releases

See ably/docs#568

lib/ably/rest/client.rb

@@ -135,7 +135,7 @@ class Client
       # @option options [Integer]                 :fallback_retry_timeout     (600 seconds) amount of time in seconds a REST client will continue to use a working fallback host when the primary fallback host has previously failed
       #
       # @option options [Boolean]                 :add_request_ids             (false) When true, adds a unique request_id to each request sent to Ably servers. This is handy when reporting issues, because you can refer to a specific request.
-      # @option options [Boolean]                 :idempotent_rest_publishing  (false) When true, idempotent publishing is enabled for all messages published via REST
+      # @option options [Boolean]                 :idempotent_rest_publishing  (false if ver < 1.2) When true, idempotent publishing is enabled for all messages published via REST
       #
       # @return [Ably::Rest::Client]
       #
@@ -171,7 +171,8 @@ def initialize(options)
         @custom_tls_port     = options.delete(:tls_port)
         @add_request_ids     = options.delete(:add_request_ids)
         @log_retries_as_info = options.delete(:log_retries_as_info)
-        @idempotent_rest_publishing = options.delete(:idempotent_rest_publishing)
+        @idempotent_rest_publishing = options.delete(:idempotent_rest_publishing) || Ably.major_minor_version_numeric > 1.1
+
 
         if options[:fallback_hosts_use_default] && options[:fallback_jhosts]
           raise ArgumentError, "fallback_hosts_use_default cannot be set to trye when fallback_jhosts is also provided"

lib/ably/version.rb

@@ -13,4 +13,9 @@ def self.lib_variant=(variant)
   def self.lib_variant
     @lib_variant
   end
+
+  # @api private
+  def self.major_minor_version_numeric
+    VERSION.gsub(/\.\d+$/, '').to_f
+  end
 end

spec/acceptance/rest/message_spec.rb

@@ -154,11 +154,17 @@
         end
       end
 
-      specify 'idempotent publishing is disabled by default (#TO3n)' do
+      specify 'idempotent publishing is disabled by default with 1.1 (#TO3n)' do
         client = Ably::Rest::Client.new(key: api_key, protocol: protocol)
         expect(client.idempotent_rest_publishing).to be_falsey
       end
 
+      specify 'idempotent publishing is enabled by default with 1.2 (#TO3n)' do
+        stub_const 'Ably::VERSION', '1.2.0'
+        client = Ably::Rest::Client.new(key: api_key, protocol: protocol)
+        expect(client.idempotent_rest_publishing).to be_truthy
+      end
+
       context 'when idempotent publishing is enabled in the client library ClientOptions (#TO3n)' do
         let(:client_options) { default_client_options.merge(idempotent_rest_publishing: true, log_level: :error) }