DConfChangeset: implement dir resets properly

If a dir is reset against a DConfChangeset then the result ought to be
that all keys under that dir read as NULL (until such a time as they are
set to a new value).

This is consistent with the (existing) behaviour that a key will read as
NULL if it, itself, was reset.

In order to make that efficient, we create a separate GHashTable to
serve as a cache of all of the directories that have been reset and
iterate it whenever we do a key lookup that doesn't have a direct hit.

We update (and expand) the test case to reflect this new reality -- the
tests actually had a case that relied on the inconsistent behaviour.

https://bugzilla.gnome.org/show_bug.cgi?id=744678

1 files changed, 24 insertions, 3 deletions

diff --git a/tests/changeset.c b/tests/changeset.c
index 90b8de6..5f046df 100644
--- a/tests/changeset.c
+++ b/tests/changeset.c
@@ -281,37 +281,58 @@ static void
 test_reset (void)
 {
   DConfChangeset *changeset;
+  GVariant *value;
 
   changeset = dconf_changeset_new ();
   g_assert (!dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (!dconf_changeset_get (changeset, "/value/a", &value));
+  /* value was not set */
 
   /* set a value */
   dconf_changeset_set (changeset, "/value/a", g_variant_new_boolean (TRUE));
   g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value != NULL);
+  g_variant_unref (value);
 
   /* record the reset */
   dconf_changeset_set (changeset, "/value/", NULL);
-  g_assert (!dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value == NULL);
 
   /* write it back */
   dconf_changeset_set (changeset, "/value/a", g_variant_new_boolean (TRUE));
   g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value != NULL);
+  g_variant_unref (value);
 
   /* reset again */
   dconf_changeset_set (changeset, "/value/", NULL);
-  g_assert (!dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value == NULL);
 
   /* write again */
   dconf_changeset_set (changeset, "/value/a", g_variant_new_boolean (TRUE));
   g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value != NULL);
+  g_variant_unref (value);
 
   /* reset a different way */
-  dconf_changeset_set (changeset, "/value/a", g_variant_new_boolean (TRUE));
+  dconf_changeset_set (changeset, "/value/a", NULL);
   g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value == NULL);
 
   /* write last time */
   dconf_changeset_set (changeset, "/value/a", g_variant_new_boolean (TRUE));
   g_assert (dconf_changeset_get (changeset, "/value/a", NULL));
+  g_assert (dconf_changeset_get (changeset, "/value/a", &value));
+  g_assert (value != NULL);
+  g_variant_unref (value);
 
   dconf_changeset_unref (changeset);
 }