[libgit2-glib] ggit-oid.c: Fix return annotations

[Igor Gnatenko <ignatenko src gnome org>]

commit 58a888b1f6817544c0550d0a13bc92a8cbd41d24
Author: Brian C. Lane <bcl redhat com>
Date:   Wed Aug 30 11:53:13 2017 -0700

    ggit-oid.c: Fix return annotations
    
    Add (nullable) where needed.

 libgit2-glib/ggit-oid.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/libgit2-glib/ggit-oid.c b/libgit2-glib/ggit-oid.c
index 4c11667..6284aa5 100644
--- a/libgit2-glib/ggit-oid.c
+++ b/libgit2-glib/ggit-oid.c
@@ -52,7 +52,7 @@ _ggit_oid_get_oid (GgitOId *oid)
  *
  * Copies @oid into a newly allocated #GgitOId.
  *
- * Returns: (transfer full): a newly allocated #GgitOId.
+ * Returns: (transfer full) (nullable): a newly allocated #GgitOId.
  */
 GgitOId *
 ggit_oid_copy (GgitOId *oid)
@@ -84,7 +84,7 @@ ggit_oid_free (GgitOId *oid)
  *
  * Parses a hex formatted object id into a #GgitOId.
  *
- * Returns: (transfer full): a newly allocated #GgitOId or %NULL on error.
+ * Returns: (transfer full) (nullable): a newly allocated #GgitOId or %NULL on error.
  */
 GgitOId *
 ggit_oid_new_from_string (const gchar *str)
@@ -108,7 +108,7 @@ ggit_oid_new_from_string (const gchar *str)
  *
  * Creates a new #GgitOId from a raw oid.
  *
- * Returns: (transfer full): a newly allocated #GgitOId.
+ * Returns: (transfer full) (nullable): a newly allocated #GgitOId or %NULL on error.
  */
 GgitOId *
 ggit_oid_new_from_raw (const guchar *raw)
@@ -147,7 +147,7 @@ ggit_oid_compare (GgitOId *a,
  *
  * Converts @oid into a readable string.
  *
- * Returns: (transfer full): a newly allocated string representing @oid.
+ * Returns: (transfer full) (nullable): a newly allocated string representing @oid or %NULL.
  */
 gchar *
 ggit_oid_to_string (GgitOId *oid)