[pygobject] tests: add a test for Gio.DBusNodeInfo.new_for_xml, see #164

[Christoph Reiter <creiter src gnome org>]

commit 0fcd57846b0053319dc5a28503d3eab173927fc6
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Wed Feb 14 00:56:47 2018 +0100

    tests: add a test for Gio.DBusNodeInfo.new_for_xml, see #164
    
    This was fixed by the recent reverts

 tests/test_gdbus.py | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
---
diff --git a/tests/test_gdbus.py b/tests/test_gdbus.py
index 2e96eb8f..18315afa 100644
--- a/tests/test_gdbus.py
+++ b/tests/test_gdbus.py
@@ -17,6 +17,35 @@ else:
     has_dbus = True
 
 
+class TestDBusNodeInfo(unittest.TestCase):
+
+    def test_new_for_xml(self):
+        info = Gio.DBusNodeInfo.new_for_xml("""
+<!DOCTYPE node PUBLIC '-//freedesktop//DTD D-BUS Object Introspection 1.0//EN'
+    'http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd'>
+<node>
+    <interface name='org.freedesktop.DBus.Introspectable'>
+        <method name='Introspect'>
+            <arg name='data' direction='out' type='s'/>
+        </method>
+    </interface>
+</node>
+""")
+
+        interfaces = info.interfaces
+        del info
+        assert len(interfaces) == 1
+        assert interfaces[0].name == "org.freedesktop.DBus.Introspectable"
+        methods = interfaces[0].methods
+        del interfaces
+        assert len(methods) == 1
+        assert methods[0].name == "Introspect"
+        out_args = methods[0].out_args
+        assert len(out_args)
+        del methods
+        assert out_args[0].name == "data"
+
+
 @unittest.skipUnless(has_dbus, "no dbus running")
 class TestGDBusClient(unittest.TestCase):
     def setUp(self):