[pygobject] Make use of instance-argument annotations

[Christoph Reiter <creiter src gnome org>]

commit fb0404c0bf08dedf657ce1384b283223b7192df1
Author: Christoph Reiter <creiter src gnome org>
Date:   Tue Mar 21 14:03:47 2017 +0100

    Make use of instance-argument annotations
    
    Use g_callable_info_get_instance_ownership_transfer() instead
    of hardcoding the transfer for instances.
    
    get_instance_ownership_transfer() is available since 1.42.0, so no
    version dependency bump is required.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=735076

 gi/pygi-cache.c          |    4 +++-
 tests/test_everything.py |    9 +++++++++
 2 files changed, 12 insertions(+), 1 deletions(-)
---
diff --git a/gi/pygi-cache.c b/gi/pygi-cache.c
index 29ea400..a106742 100644
--- a/gi/pygi-cache.c
+++ b/gi/pygi-cache.c
@@ -975,14 +975,16 @@ _function_with_instance_cache_generate_args_cache_real (PyGICallableCache *calla
 {
     GIInterfaceInfo *interface_info;
     PyGIArgCache *instance_cache;
+    GITransfer transfer;
 
     interface_info = g_base_info_get_container ((GIBaseInfo *) callable_info);
+    transfer = g_callable_info_get_instance_ownership_transfer (callable_info);
 
     instance_cache =
         _arg_cache_new_for_interface (interface_info,
                                       NULL,
                                       NULL,
-                                      GI_TRANSFER_NOTHING,
+                                      transfer,
                                       PYGI_DIRECTION_FROM_PYTHON,
                                       callable_cache);
 
diff --git a/tests/test_everything.py b/tests/test_everything.py
index 0b5cf6d..fae07e6 100644
--- a/tests/test_everything.py
+++ b/tests/test_everything.py
@@ -54,6 +54,15 @@ class RawGList(ctypes.Structure):
 
 
 @unittest.skipUnless(has_cairo, 'built without cairo support')
+class TestInstanceTransfer(unittest.TestCase):
+
+    def test_main(self):
+        obj = Everything.TestObj()
+        for _ in range(10):
+            obj.instance_method_full()
+
+
+@unittest.skipUnless(has_cairo, 'built without cairo support')
 class TestEverything(unittest.TestCase):
 
     def test_bool(self):