Return proper exit code for TERM signal

lib/puma/cluster.rb

@@ -375,7 +375,10 @@ def setup_signals
           log "Early termination of worker"
           exit! 0
         else
+          stop_workers
           stop
+
+          raise SignalException, "SIGTERM"
         end
       end
     end

lib/puma/launcher.rb

@@ -392,7 +392,9 @@ def setup_signals
 
       begin
         Signal.trap "SIGTERM" do
-          stop
+          graceful_stop
+
+          raise SignalException, "SIGTERM"
         end
       rescue Exception
         log "*** SIGTERM not implemented, signal based gracefully stopping unavailable!"

test/test_integration.rb

@@ -53,6 +53,21 @@ def server(argv)
     @server
   end
 
+  def start_forked_server(argv)
+    pid = fork do
+      exec "#{Gem.ruby} -I lib/ bin/puma -b tcp://127.0.0.1:#{@tcp_port} #{argv}"
+    end
+
+    sleep 5
+    pid
+  end
+
+  def stop_forked_server(pid)
+    Process.kill(:TERM, pid)
+    sleep 1
+    Process.wait2(pid)
+  end
+
   def restart_server_and_listen(argv)
     skip_on_appveyor
     server(argv)
@@ -218,4 +233,22 @@ def test_restart_restores_environment
     assert_includes new_reply, "Hello RAND"
     refute_equal initial_reply, new_reply
   end
+
+  def test_term_signal_exit_code_in_single_mode
+    skip if Puma.jruby? || Puma.windows?
+
+    pid = start_forked_server("test/rackup/hello.ru")
+    _, status = stop_forked_server(pid)
+
+    assert_equal 15, status
+  end
+
+  def test_term_signal_exit_code_in_clustered_mode
+    skip if Puma.jruby? || Puma.windows?
+
+    pid = start_forked_server("-w 2 test/rackup/hello.ru")
+    _, status = stop_forked_server(pid)
+
+    assert_equal 15, status
+  end
 end