Add a test for retry_intervals as a lambda

lib/shoryuken/middleware/server/exponential_backoff_retry.rb

@@ -27,7 +27,7 @@ def call(worker, queue, sqs_msg, body)
         def get_interval(retry_intervals, attempts)
           return retry_intervals.call(attempts) if retry_intervals.respond_to?(:call)
 
-          # Array start at 0
+          # Arrays start at 0
           attempts -= 1
 
           if attempts < (retry_intervals = Array(retry_intervals)).size
@@ -44,9 +44,9 @@ def next_visibility_timeout(interval, started_at)
         end
 
         def handle_failure(sqs_msg, started_at, retry_intervals)
-          return false unless sqs_msg.attributes['ApproximateReceiveCount']
+          return false if (receive_count = sqs_msg.attributes['ApproximateReceiveCount'].to_i).zero?
 
-          return false unless (interval = get_interval(retry_intervals, sqs_msg.attributes['ApproximateReceiveCount'].to_i))
+          return false unless (interval = get_interval(retry_intervals, receive_count))
 
           sqs_msg.change_visibility(visibility_timeout: next_visibility_timeout(interval, started_at))
 

spec/shoryuken/middleware/server/exponential_backoff_retry_spec.rb

@@ -39,6 +39,14 @@
     end
 
     context 'and retry_intervals is a lambda' do
+      it 'retries' do
+        TestWorker.get_shoryuken_options['retry_intervals'] = ->(_attempts) { 500 }
+
+        allow(sqs_msg).to receive(:queue) { sqs_queue }
+        expect(sqs_msg).to receive(:change_visibility).with(visibility_timeout: 500)
+
+        expect { subject.call(TestWorker.new, queue, sqs_msg, sqs_msg.body) { raise 'failed' } }.not_to raise_error
+      end
     end
 
     context 'and retry_intervals is empty' do