Address thread pool test TODOs [changelog skip]

test/test_thread_pool.rb

@@ -223,27 +223,32 @@ def test_reap_only_dead_threads
   def test_auto_reap_dead_threads
     pool = new_pool(2,2) { Thread.current.kill }
 
+    pool.auto_reap! 0.1
+
+    pause
+
     assert_equal 2, pool.spawned
 
-    # TODO: is there a point to these two lines?
     pool << 1
     pool << 2
 
-    pool.auto_reap! 0.1
-
     pause
 
     assert_equal 0, pool.spawned
   end
 
   def test_force_shutdown_immediately
+    finish = false
+    rescued = false
+
     pool = new_pool(0, 1) do |work|
       begin
         @work_mutex.synchronize do
           @work_done.signal
         end
-        sleep 10 # TODO: do something here other than sleep
+        Thread.pass until finish
       rescue Puma::ThreadPool::ForceShutdown
+        rescued = true
       end
     end
 
@@ -252,7 +257,9 @@ def test_force_shutdown_immediately
     @work_mutex.synchronize do
       @work_done.wait(@work_mutex, 5)
       pool.shutdown(0)
+      finish = true
       assert_equal 0, pool.spawned
+      assert rescued
     end
   end
 end