rename shift_and_perform to perform_one

Changes.md

@@ -7,6 +7,8 @@ HEAD
   Sidekiq::Job#enqueued\_at to query the time. [mariovisic, #944]
 - Add Sidekiq::Queue#latency - calculates diff between now and
   enqueued\_at for the oldest job in the queue.
+- Add testing method `perform_one` that dequeues and performs a single job.
+  This is mainly to aid testing jobs that spawn other jobs. [fumin, #963]
 
 2.12.0
 -----------

lib/sidekiq/testing.rb

@@ -89,7 +89,7 @@ module Sidekiq
       end
 
       # Pop out a single job and perform it
-      def shift_and_perform
+      def perform_one
         job = jobs.shift
         new.perform(*job['args'])
       end

test/test_testing.rb

@@ -119,12 +119,12 @@ class TestTesting < Minitest::Test
       StoredWorker.clear
     end
 
-    it 'shift_and_perform runs only one job' do
+    it 'perform_one runs only one job' do
       DirectWorker.perform_async(1, 2)
       DirectWorker.perform_async(3, 4)
       assert_equal 2, DirectWorker.jobs.size
 
-      DirectWorker.shift_and_perform
+      DirectWorker.perform_one
       assert_equal 1, DirectWorker.jobs.size
 
       DirectWorker.clear