Add ordered iterator for JsonObject

The current iterator API does not guarantee the iteration order, as it's
based off of the hash table iterator. JsonObject, though, can guarantee
the iteration order—we do that for json_object_foreach_member().

Instead of changing the behaviour of json_object_iter_next(), we can add
API to initialize and iterate a JsonObjectIter in insertion order.

1 files changed, 50 insertions, 8 deletions

diff --git a/json-glib/tests/object.c b/json-glib/tests/object.c
index 772265a..fa2efd2 100644
--- a/json-glib/tests/object.c
+++ b/json-glib/tests/object.c
@@ -106,6 +106,7 @@ test_remove_member (void)
 typedef struct _TestForeachFixture
 {
   gint n_members;
+  gboolean ordered;
 } TestForeachFixture;
 
 static const struct {
@@ -128,15 +129,27 @@ verify_foreach (JsonObject  *object,
                 gpointer     user_data)
 {
   TestForeachFixture *fixture = user_data;
-  gint i;
 
-  for (i = 0; i < G_N_ELEMENTS (type_verify); i++)
+  if (fixture->ordered)
     {
-      if (strcmp (member_name, type_verify[i].member_name) == 0)
+      int idx = fixture->n_members;
+
+      g_assert_cmpstr (member_name, ==, type_verify[idx].member_name);
+      g_assert_true (json_node_get_node_type (member_node) == type_verify[idx].member_type);
+      g_assert_true (json_node_get_value_type (member_node) == type_verify[idx].member_gtype);
+    }
+  else
+    {
+      int i;
+
+      for (i = 0; i < G_N_ELEMENTS (type_verify); i++)
         {
-          g_assert (json_node_get_node_type (member_node) == type_verify[i].member_type);
-          g_assert (json_node_get_value_type (member_node) == type_verify[i].member_gtype);
-          break;
+          if (strcmp (member_name, type_verify[i].member_name) == 0)
+            {
+              g_assert_true (json_node_get_node_type (member_node) == type_verify[i].member_type);
+              g_assert_true (json_node_get_value_type (member_node) == type_verify[i].member_gtype);
+              break;
+            }
         }
     }
 
@@ -147,7 +160,7 @@ static void
 test_foreach_member (void)
 {
   JsonObject *object = json_object_new ();
-  TestForeachFixture fixture = { 0, };
+  TestForeachFixture fixture = { 0, TRUE, };
 
   json_object_set_int_member (object, "integer", 42);
   json_object_set_boolean_member (object, "boolean", TRUE);
@@ -167,7 +180,7 @@ static void
 test_iter (void)
 {
   JsonObject *object = NULL;
-  TestForeachFixture fixture = { 0, };
+  TestForeachFixture fixture = { 0, FALSE, };
   JsonObjectIter iter;
   const gchar *member_name;
   JsonNode *member_node;
@@ -192,6 +205,34 @@ test_iter (void)
 }
 
 static void
+test_ordered_iter (void)
+{
+  JsonObject *object = NULL;
+  TestForeachFixture fixture = { 0, TRUE, };
+  JsonObjectIter iter;
+  const gchar *member_name;
+  JsonNode *member_node;
+
+  object = json_object_new ();
+
+  json_object_set_int_member (object, "integer", 42);
+  json_object_set_boolean_member (object, "boolean", TRUE);
+  json_object_set_string_member (object, "string", "hello");
+  json_object_set_double_member (object, "double", 3.14159);
+  json_object_set_null_member (object, "null");
+  json_object_set_int_member (object, "", 0);
+
+  json_object_iter_init_ordered (&iter, object);
+
+  while (json_object_iter_next_ordered (&iter, &member_name, &member_node))
+    verify_foreach (object, member_name, member_node, &fixture);
+
+  g_assert_cmpint (fixture.n_members, ==, json_object_get_size (object));
+
+  json_object_unref (object);
+}
+
+static void
 test_empty_member (void)
 {
   JsonObject *object = json_object_new ();
@@ -227,6 +268,7 @@ main (int   argc,
   g_test_add_func ("/object/remove-member", test_remove_member);
   g_test_add_func ("/object/foreach-member", test_foreach_member);
   g_test_add_func ("/object/iter", test_iter);
+  g_test_add_func ("/object/ordered-iter", test_ordered_iter);
   g_test_add_func ("/object/empty-member", test_empty_member);
 
   return g_test_run ();