[pygobject] Handle nullable filename parameters

[Christoph Reiter <creiter src gnome org>]

commit 7ccc164b6da6d87c0a200ea50314d213470a1f18
Author: Christoph Reiter <creiter src gnome org>
Date:   Sat Sep 3 20:02:13 2016 +0200

    Handle nullable filename parameters
    
    Make _pygi_marshal_from_py_filename handle None input
    values. This allows one to pass None to parameters
    annotated as nullable filenames.
    
    This fixes a test suite error in test_spawn_async_with_pipes
    triggered by an annotation change in glib.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=770821

 gi/pygi-basictype.c             |    5 +++++
 tests/gimarshallingtestsextra.c |   22 ++++++++++++++++++++++
 tests/gimarshallingtestsextra.h |    3 +++
 tests/test_gi.py                |    4 ++++
 4 files changed, 34 insertions(+), 0 deletions(-)
---
diff --git a/gi/pygi-basictype.c b/gi/pygi-basictype.c
index b6515c3..4a5e112 100644
--- a/gi/pygi-basictype.c
+++ b/gi/pygi-basictype.c
@@ -255,6 +255,11 @@ _pygi_marshal_from_py_filename (PyObject          *py_arg,
     GError *error = NULL;
     PyObject *tmp = NULL;
 
+    if (py_arg == Py_None) {
+        arg->v_pointer = NULL;
+        return TRUE;
+    }
+
     if (PyUnicode_Check (py_arg)) {
         tmp = PyUnicode_AsUTF8String (py_arg);
         if (!tmp)
diff --git a/tests/gimarshallingtestsextra.c b/tests/gimarshallingtestsextra.c
index 56b0113..85a9fba 100644
--- a/tests/gimarshallingtestsextra.c
+++ b/tests/gimarshallingtestsextra.c
@@ -68,3 +68,25 @@ gi_marshalling_tests_ghashtable_enum_none_return (void)
 
   return hash_table;
 }
+
+/**
+ * gi_marshalling_tests_filename_copy:
+ * @path_in: (type filename) (nullable)
+ *
+ * Returns: (type filename) (nullable)
+ */
+gchar *
+gi_marshalling_tests_filename_copy (gchar *path_in)
+{
+  return g_strdup (path_in);
+}
+
+/**
+ * gi_marshalling_tests_filename_exists:
+ * @path: (type filename)
+ */
+gboolean
+gi_marshalling_tests_filename_exists (gchar *path)
+{
+  return g_file_test (path, G_FILE_TEST_EXISTS);
+}
diff --git a/tests/gimarshallingtestsextra.h b/tests/gimarshallingtestsextra.h
index ae6be1b..51a65f2 100644
--- a/tests/gimarshallingtestsextra.h
+++ b/tests/gimarshallingtestsextra.h
@@ -33,4 +33,7 @@ void gi_marshalling_tests_compare_two_gerrors_in_gvalue (GValue *v, GValue *v1);
 void gi_marshalling_tests_ghashtable_enum_none_in (GHashTable *hash_table);
 GHashTable * gi_marshalling_tests_ghashtable_enum_none_return (void);
 
+gchar * gi_marshalling_tests_filename_copy (gchar *path_in);
+gboolean gi_marshalling_tests_filename_exists (gchar *path);
+
 #endif /* EXTRA_TESTS */
diff --git a/tests/test_gi.py b/tests/test_gi.py
index d246a01..d0c72b6 100644
--- a/tests/test_gi.py
+++ b/tests/test_gi.py
@@ -710,6 +710,10 @@ class TestFilename(unittest.TestCase):
         self.assertEqual(result, True)
         self.assertEqual(contents, b'hello world!\n\x01\x02')
 
+    def test_filename_in_nullable(self):
+        self.assertTrue(GIMarshallingTests.filename_copy(None) is None)
+        self.assertRaises(TypeError, GIMarshallingTests.filename_exists, None)
+
     def test_filename_out(self):
         self.assertRaises(GLib.GError, GLib.Dir.make_tmp, 'test')