Menu items do not get localized (report+patch)

Problem

1. Create a menu with items set to 'All Languages'
2. Use the interface translation to translate these menu items
3. Switch to the langauge you translated into. The translations don't appear.

Analysis

The i18nblocks module uses theme('blocks') to translate the menu item. It does this by overriding the system's default themer, in i18nblocks_theme.
However, by default i18nblocks has the same weight as the system module - this means that system_theme is called after i18nblocks_theme (as it's done by weight, then alphabetically), and therefore the override does not work.

Solution

At the very least, the weight of the i18nblocks module should be set in the .install file. Ideally, there should be an i18nblocks admin page that warns you when the weight of 18nblocks is lower or equal to that of the system blocks ; and that lets you change that weight. Both patches are provided below.

Patch

First, a patch to the .install file :

Index: modules/i18n/i18nblocks/i18nblocks.install
===================================================================
--- modules/i18n/i18nblocks/i18nblocks.install  (revision 1293)
+++ modules/i18n/i18nblocks/i18nblocks.install  (working copy)
@@ -8,8 +8,8 @@
 function i18nblocks_install() {
   // Create database tables
   drupal_install_schema('i18nblocks');
-  // We dont need to change module weight
-  //db_query("UPDATE {system} SET weight = 20 WHERE name = 'i18nblocks' AND type = 'module'");
+  // We do need to change module weight
+  db_query("UPDATE {system} SET weight = 20 WHERE name = 'i18nblocks' AND type = 'module'");
 }

 /**

Next, a patch to create an admin page and set the weight :

Index: modules/i18n/i18n.admin.inc
===================================================================
--- modules/i18n/i18n.admin.inc (revision 1293)
+++ modules/i18n/i18n.admin.inc (working copy)
@@ -29,9 +29,59 @@
     '#options' => _i18n_selection_mode(),
     '#description' => t('Determines which content to show depending on the current page language and the default language of the site.'),
   );
-  return system_settings_form($form);
+  if (module_exists('i18nblocks')) {
+    $blocks_weight = db_result(db_query("SELECT weight FROM {system} WHERE name = 'i18nblocks' AND type='module'"));
+    $system_weight = db_result(db_query("SELECT max(weight) FROM {system} WHERE name = 'system' AND type='module'"));
+
+    $form['i18nblocks'] = array(
+      '#type' => 'fieldset',
+      '#title' => t('i18nblocks module configuration'),
+    );
+    $form['i18nblocks']['weight'] = array(
+      '#type' => 'textfield',
+      '#title' => t('Module weight'),
+      '#description' => t(
+        'In order to function properly, the i18nblocks module must be heavier than the system module. The system module currently weights %weight',
+        array('%weight' => $system_weight)
+       ),
+      '#default_value' => $blocks_weight,
+    );
+  }
+
+  // We don't use the default system form settings, as we want to update the weight of the module
+  // straight away.
+  $form['buttons']['submit'] = array('#type' => 'submit', '#value' => t('Save configuration') );
+  $form['buttons']['reset'] = array('#type' => 'submit', '#value' => t('Reset to defaults') );
+
+  if (!empty($_POST) && form_get_errors()) {
+    drupal_set_message(t('The settings have not been saved because of the errors.'), 'error');
+  }
+  $form['#submit'][] = 'i18n_admin_settings_callback';
+  $form['#theme'] = 'system_settings_form';
+  return $form;
 }

+/**
+ * Save the admin page settings form
+ */
+function i18n_admin_settings_callback($form, &$form_state) {
+  if (isset($form_state['values']['op']) &&
+      $form_state['values']['op'] == t('Reset to defaults')) {
+    variable_del('i18n_selection_mode');
+    drupal_set_message(t('The configuration options have been reset to their default values.'));
+  } else {
+    variable_set('i18n_selection_mode', $form_state['values']['i18n_selection_mode']);
+    if (module_exists('i18nblocks')) {
+      db_query("UPDATE {system} SET weight='".intval($form_state['values']['weight'])."' "
+               ." WHERE type='module' AND name='i18nblocks'");
+    }
+    drupal_set_message(t('The configuration options have been saved.'));
+  }
+
+  cache_clear_all();
+  drupal_rebuild_theme_registry();
+}
+
 // List of selection modes
 function _i18n_selection_mode(){
   return array(