eliminate redundant server_close() (#2041)

pymodbus/server/async_io.py

@@ -283,10 +283,6 @@ def callback_new_connection(self):
         return ModbusServerRequestHandler(self)
 
     async def shutdown(self):
-        """Shutdown server."""
-        await self.server_close()
-
-    async def server_close(self):
         """Close server."""
         if not self.serving.done():
             self.serving.set_result(True)

test/sub_server/test_server_asyncio.py

@@ -125,7 +125,7 @@ async def _setup_teardown(self):
 
         # teardown
         if self.server is not None:
-            await self.server.server_close()
+            await self.server.shutdown()
             self.server = None
         if self.task is not None:
             await asyncio.sleep(0.1)
@@ -239,15 +239,15 @@ async def test_async_tcp_server_connection_lost(self):
         BasicClient.transport.close()
         await asyncio.sleep(0.2)  # so we have to wait a bit
 
-    async def test_async_tcp_server_close_connection(self):
-        """Test server_close() while there are active TCP connections."""
+    async def test_async_tcp_server_shutdown_connection(self):
+        """Test server shutdown() while there are active TCP connections."""
         await self.start_server()
         await self.connect_server()
 
         # On Windows we seem to need to give this an extra chance to finish,
         # otherwise there ends up being an active connection at the assert.
         await asyncio.sleep(0.5)
-        await self.server.server_close()
+        await self.server.shutdown()
 
     async def test_async_tcp_server_no_slave(self):
         """Test unknown slave exception."""
@@ -258,7 +258,7 @@ async def test_async_tcp_server_no_slave(self):
         await self.start_server()
         await self.connect_server()
         assert not BasicClient.eof.done()
-        await self.server.server_close()
+        await self.server.shutdown()
         self.server = None
 
     async def test_async_tcp_server_modbus_error(self):
@@ -313,7 +313,7 @@ async def test_async_start_udp_server(self):
     async def test_async_udp_server_serve_forever_close(self):
         """Test StarAsyncUdpServer serve_forever() method."""
         await self.start_server(do_udp=True)
-        await self.server.server_close()
+        await self.server.shutdown()
         self.server = None
 
     async def test_async_udp_server_serve_forever_twice(self):