tp_connection_dup_contact_by_id_async: don't crash without Contacts

Signed-off-by: Simon McVittie <simon.mcvittie@collabora.co.uk>
Reviewed-by: Guillaume Desmottes <guillaume.desmottes@collabora.co.uk>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=49735

2 files changed, 50 insertions, 6 deletions

diff --git a/telepathy-glib/contact.c b/telepathy-glib/contact.c
index a80c7785f..6f17769f7 100644
--- a/telepathy-glib/contact.c
+++ b/telepathy-glib/contact.c
@@ -4738,8 +4738,6 @@ tp_connection_dup_contact_by_id_async (TpConnection *self,
   if (!get_feature_flags (n_features, features, &feature_flags))
     return;
 
-  supported_interfaces = contacts_bind_to_signals (self, feature_flags);
-
   result = g_simple_async_result_new ((GObject *) self, callback, user_data,
       tp_connection_dup_contact_by_id_async);
 
@@ -4748,11 +4746,33 @@ tp_connection_dup_contact_by_id_async (TpConnection *self,
   data->features_array = g_array_sized_new (FALSE, FALSE,
       sizeof (TpContactFeature), n_features);
   g_array_append_vals (data->features_array, features, n_features);
-  tp_cli_connection_interface_contacts_call_get_contact_by_id (self, -1,
-      id, supported_interfaces, got_contact_by_id_cb,
-      data, NULL, NULL);
 
-  g_free (supported_interfaces);
+  if (tp_proxy_has_interface_by_id (self,
+        TP_IFACE_QUARK_CONNECTION_INTERFACE_CONTACTS))
+    {
+      supported_interfaces = contacts_bind_to_signals (self, feature_flags);
+
+      tp_cli_connection_interface_contacts_call_get_contact_by_id (self, -1,
+          id, supported_interfaces, got_contact_by_id_cb,
+          data, NULL, NULL);
+
+      g_free (supported_interfaces);
+    }
+  else
+    {
+      /* Proceed directly to the slow path, do not pass Go, do not collect
+       * £200. contacts_bind_to_signals() relies on having Contacts. */
+
+      G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+      tp_connection_get_contacts_by_id (self, 1,
+          (const gchar * const *) &data->id,
+          data->features_array->len,
+          (TpContactFeature *) data->features_array->data,
+          got_contact_by_id_fallback_cb,
+          data, (GDestroyNotify) contacts_async_data_free, NULL);
+      G_GNUC_END_IGNORE_DEPRECATIONS
+    }
+
   g_object_unref (result);
 }
 
diff --git a/tests/dbus/contacts-slow-path.c b/tests/dbus/contacts-slow-path.c
index 31c22f7e3..fa4b454e2 100644
--- a/tests/dbus/contacts-slow-path.c
+++ b/tests/dbus/contacts-slow-path.c
@@ -1005,6 +1005,28 @@ test_by_id (Fixture *f,
 }
 
 static void
+test_one_by_id (Fixture *f,
+    gconstpointer unused G_GNUC_UNUSED)
+{
+  GAsyncResult *result = NULL;
+  GError *error = NULL;
+  TpContact *contact;
+
+  tp_connection_dup_contact_by_id_async (f->legacy_client_conn,
+      "Alice", 0, NULL, tp_tests_result_ready_cb, &result);
+  tp_tests_run_until_result (&result);
+  contact = tp_connection_dup_contact_by_id_finish (f->legacy_client_conn,
+      result, &error);
+
+  g_assert_no_error (error);
+  g_assert (TP_IS_CONTACT (contact));
+  g_assert_cmpstr (tp_contact_get_identifier (contact), ==, "alice");
+
+  g_clear_object (&result);
+  g_clear_object (&contact);
+}
+
+static void
 test_by_handle_again (Fixture *f,
     gconstpointer unused G_GNUC_UNUSED)
 {
@@ -1271,6 +1293,8 @@ main (int argc,
       test_by_handle_upgrade, teardown);
   g_test_add ("/contacts-slow-path/dup-if-possible", Fixture, NULL, setup,
       test_dup_if_possible, teardown);
+  g_test_add ("/contacts-slow-path/one-by-id", Fixture, NULL, setup,
+      test_one_by_id, teardown);
 
   return g_test_run ();
 }