Change rpc server example to use simple restore function

examples/calculator_server.py

@@ -130,15 +130,7 @@ given address/port ADDRESS may be '*' to bind to all local addresses.\
     return parser.parse_args()
 
 
-class CalcRestorer:
-
-    '''A RPC Restorer. This requires a `restore` function to be defined, and
-    will be passed in a SturdyRef by your client'''
-
-    def __init__(self):
-        self.calc = CalculatorImpl()
-
-    def restore(self, ref):
+def restore(ref):
     assert ref.as_text() == 'calculator'
     return CalculatorImpl()
 
@@ -169,8 +161,7 @@ def main():
     while True:
         try:
             (clientsocket, address) = s.accept()
-            restorer = CalcRestorer()
-            server = capnp.TwoPartyServer(clientsocket, restorer)
+            server = capnp.TwoPartyServer(clientsocket, restore)
 
             server.run_forever()
             print("client disconnected")

test/test_rpc_calculator.py

@@ -0,0 +1,35 @@
+import capnp
+import os
+import socket
+import gc
+
+import sys  # add examples dir to sys.path
+sys.path.append(os.path.join(os.path.dirname(__file__), '..', 'examples'))
+import calculator_client
+import calculator_server
+
+
+def test_calculator():
+    read, write = socket.socketpair(socket.AF_UNIX)
+
+    server = capnp.TwoPartyServer(write, calculator_server.restore)
+    calculator_client.main(read)
+
+
+def test_calculator_gc():
+    def new_evaluate_impl(old_evaluate_impl):
+        def call(*args, **kwargs):
+            gc.collect()
+            return old_evaluate_impl(*args, **kwargs)
+        return call
+
+    read, write = socket.socketpair(socket.AF_UNIX)
+
+    # inject a gc.collect to the beginning of every evaluate_impl call
+    evaluate_impl_orig = calculator_server.evaluate_impl
+    calculator_server.evaluate_impl = new_evaluate_impl(evaluate_impl_orig)
+
+    server = capnp.TwoPartyServer(write, calculator_server.restore)
+    calculator_client.main(read)
+
+    calculator_server.evaluate_impl = evaluate_impl_orig