[gnome-photos/wip/rishi/import-0: 1/5] source: Prevent the ID and name from getting overwritten

[Debarshi Ray <debarshir src gnome org>]

commit 34965b2d8eda41483626aa23bc7518e1b9d8099e
Author: Debarshi Ray <debarshir gnome org>
Date:   Thu Jan 11 19:04:54 2018 +0100

    source: Prevent the ID and name from getting overwritten
    
    The "id" and "name" properties of a Source created from a GoaObject are
    set based on attributes of the GoaObject, and are not separately routed
    through GObject's property machinery. Since they are marked as
    construct properties, GObject will set them to their default values,
    which is NULL in both cases, regardless of whether they were already
    set outside of the property machinery.
    
    This hasn't been a problem so far because GObject sorts the construct
    properties alphabetically before setting them, and "id" and "name"
    precede "object". This will break when a "mount" property, analogous to
    "object", for GMount-backed sources gets added in a subsequent commit.
    
    https://gitlab.gnome.org/GNOME/gnome-photos/issues/29

 src/photos-source.c | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)
---
diff --git a/src/photos-source.c b/src/photos-source.c
index 845f1c86..500dccc7 100644
--- a/src/photos-source.c
+++ b/src/photos-source.c
@@ -241,12 +241,30 @@ photos_source_set_property (GObject *object, guint prop_id, const GValue *value,
       break;
 
     case PROP_ID:
-      self->id = g_value_dup_string (value);
-      break;
+      {
+        const gchar *id;
+
+        id = g_value_get_string (value);
+        g_return_if_fail (self->id == NULL || id == NULL);
+
+        if (self->id == NULL && id != NULL)
+          self->id = g_strdup (id);
+
+        break;
+      }
 
     case PROP_NAME:
-      self->name = g_value_dup_string (value);
-      break;
+      {
+        const gchar *name;
+
+        name = g_value_get_string (value);
+        g_return_if_fail (self->name == NULL || name == NULL);
+
+        if (self->name == NULL && name != NULL)
+          self->name = g_strdup (name);
+
+        break;
+      }
 
     case PROP_OBJECT:
       {