Add test for returning tuple in server

test/test_capability.capnp

@@ -27,6 +27,7 @@ interface TestInterface {
   foo @0 (i :UInt32, j :Bool) -> (x: Text);
   bar @1 () -> ();
   buz @2 (i: TestSturdyRefHostId) -> (x: Text);
+  bam @3 (i :UInt32, j :Bool) -> (x: Text, i:UInt32);
   # baz @2 (s: TestAllTypes);
 }
 

test/test_capability.py

@@ -17,6 +17,9 @@ class Server(capability.TestInterface.Server):
     def buz(self, i, **kwargs):
         return i.host + '_test'
 
+    def bam(self, i, **kwargs):
+        return str(i) + '_test', i
+
 class PipelineServer(capability.TestPipeline.Server):
     def getCap(self, n, inCap, _context, **kwargs):
         def _then(response):
@@ -97,6 +100,12 @@ def test_simple_client():
 
     assert response.x == 'localhost_test'
 
+    remote = client.bam(i=5)
+    response = remote.wait()
+
+    assert response.x == '5_test'
+    assert response.i == 5
+
     with pytest.raises(ValueError):
         remote = client.foo(5, 10)