Fix rescuing errors in RedisProxy#increment

lib/rack/attack/store_proxy/redis_proxy.rb

@@ -31,16 +31,12 @@ module Rack
         end
 
         def increment(key, amount, options = {})
-          count = nil
-
           rescuing do
             pipelined do
-              count = incrby(key, amount)
+              incrby(key, amount)
               expire(key, options[:expires_in]) if options[:expires_in]
-            end
+            end.first
           end
-
-          count.value if count
         end
 
         def delete(key, _options = {})

spec/integration/offline_spec.rb

@@ -45,3 +45,15 @@ if defined?(::Dalli)
     end
   end
 end
+
+if defined?(Redis)
+  describe 'when Redis is offline' do
+    include OfflineExamples
+
+    before do
+      @cache = Rack::Attack::Cache.new
+      # Use presumably unused port for Redis client
+      @cache.store = Redis.new(host: '127.0.0.1', port: 3333)
+    end
+  end
+end