- Patch #657972 by plach, Berdir: make field fallback logic actually reusable.

modules/field/field.api.php

@@ -1062,11 +1062,43 @@ function hook_field_attach_delete_revision($entity_type, $entity) {
  *   - obj_type: The type of $entity; e.g. 'node' or 'user'.
  *   - object: The entity with fields to render.
  *   - view_mode: View mode, e.g. 'full', 'teaser'...
- *   - langcode: The language in which the field values will be displayed.
  */
 function hook_field_attach_view_alter(&$output, $context) {
 }
 
+/**
+ * Act on field_language().
+ *
+ * This hook is invoked to alter the array of display languages for the given
+ * entity.
+ *
+ * @param $display_language
+ *   A reference to an array of language codes keyed by field name.
+ * @param $context
+ *   An associative array containing:
+ *   - entity_type: The type of the entity to be displayed.
+ *   - entity: The entity with fields to render.
+ *   - langcode: The language code $entity has to be displayed in.
+ */
+function hook_field_language_alter(&$display_language, $context) {
+}
+
+/**
+ * Act on field_available_languages().
+ *
+ * This hook is invoked to alter the array of available languages for the given
+ * field.
+ *
+ * @param &$languages
+ *   A reference to an array of language codes to be made available.
+ * @param $context
+ *   An associative array containing:
+ *   - entity_type: The type of the entity the field is attached to.
+ *   - field: A field data structure.
+ */
+function hook_field_available_languages_alter(&$languages, $context) {
+}
+
 /**
  * Act on field_attach_create_bundle.
  *

modules/field/field.attach.inc

@@ -168,6 +168,9 @@ class FieldQueryException extends FieldException {}
  *  - 'deleted': If TRUE, the function will operate on deleted fields
  *    as well as non-deleted fields. If unset or FALSE, only
  *    non-deleted fields are operated on.
+ *  - 'language': A language code or an array of language codes keyed by field
+ *    name. It will be used to narrow down to a single value the available
+ *    languages to act on.
  */
 function _field_invoke($op, $entity_type, $entity, &$a = NULL, &$b = NULL, $options = array()) {
   // Merge default options.
@@ -196,10 +199,14 @@ function _field_invoke($op, $entity_type, $entity, &$a = NULL, &$b = NULL, $opti
     if ((!isset($options['field_id']) || $options['field_id'] == $instance['field_id']) && (!isset($options['field_name']) || $options['field_name'] == $field_name)) {
       $field = field_info_field($field_name);
       $field_translations = array();
-      $suggested_languages = empty($options['language']) ? NULL : array($options['language']);
+
+      // Unless a language suggestion is provided we iterate on all the
+      // available languages.
+      $available_languages = field_available_languages($entity_type, $field);
+      $languages = _field_language_suggestion($available_languages, $options['language'], $field_name);
 
       // Initialize field translations according to the available languages.
-      foreach (field_multilingual_available_languages($entity_type, $field, $suggested_languages) as $langcode) {
+      foreach ($languages as $langcode) {
         $field_translations[$langcode] = isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : array();
       }
 
@@ -271,6 +278,10 @@ function _field_invoke($op, $entity_type, $entity, &$a = NULL, &$b = NULL, $opti
  *  - 'deleted': If TRUE, the function will operate on deleted fields
  *    as well as non-deleted fields. If unset or FALSE, only
  *    non-deleted fields are operated on.
+ *  - 'language': A language code or an array of language codes keyed by field
+ *    name. It will be used to narrow down to a single value the available
+ *    languages to act on.
+ *
  * @return
  *   An array of returned values keyed by entity id.
  */
@@ -321,8 +332,11 @@ function _field_invoke_multiple($op, $entity_type, $entities, &$a = NULL, &$b =
         $grouped_entities[$field_id][$id] = $entities[$id];
         // Extract the field values into a separate variable, easily accessed
         // by hook implementations.
-        $suggested_languages = empty($options['language']) ? NULL : array($options['language']);
-        foreach (field_multilingual_available_languages($entity_type, $fields[$field_id], $suggested_languages) as $langcode) {
+        // Unless a language suggestion is provided we iterate on all the
+        // available languages.
+        $available_languages = field_available_languages($entity_type, $fields[$field_id]);
+        $languages = _field_language_suggestion($available_languages, $options['language'], $field_name);
+        foreach ($languages as $langcode) {
           $grouped_items[$field_id][$langcode][$id] = isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : array();
         }
       }
@@ -492,7 +506,7 @@ function _field_invoke_multiple_default($op, $entity_type, $entities, &$a = NULL
  */
 function field_attach_form($entity_type, $entity, &$form, &$form_state, $langcode = NULL) {
   // If no language is provided use the default site language.
-  $options = array('language' => field_multilingual_valid_language($langcode));
+  $options = array('language' => field_valid_language($langcode));
   $form += (array) _field_invoke_default('form', $entity_type, $entity, $form, $form_state, $options);
 
   // Add custom weight handling.
@@ -1200,9 +1214,12 @@ function field_attach_prepare_view($entity_type, $entities, $view_mode = 'full')
  *   A renderable array for the field values.
  */
 function field_attach_view($entity_type, $entity, $view_mode = 'full', $langcode = NULL) {
-  // Invoke field_default_view(). If no language is provided, use the current
-  // UI language.
-  $options = array('language' => field_multilingual_valid_language($langcode, FALSE));
+  // Determine the actual language to display for each field, given the
+  // languages available in the field data.
+  $display_language = field_language($entity_type, $entity, NULL, $langcode);
+  $options = array('language' => $display_language);
+
+  // Invoke field_default_view().
   $null = NULL;
   $output = _field_invoke_default('view', $entity_type, $entity, $view_mode, $null, $options);
 
@@ -1219,7 +1236,6 @@ function field_attach_view($entity_type, $entity, $view_mode = 'full', $langcode
     'obj_type' => $entity_type,
     'object' => $entity,
     'view_mode' => $view_mode,
-    'langcode' => $langcode,
   );
   drupal_alter('field_attach_view', $output, $context);
 

modules/field/field.module

@@ -496,10 +496,8 @@ function field_view_value($entity_type, $entity, $field_name, $item, $display =
   $output = array();
 
   if ($field = field_info_field($field_name)) {
-    $langcode = field_multilingual_valid_language($langcode, FALSE);
-
     // Determine the langcode that will be used by language fallback.
-    $langcode = current(field_multilingual_available_languages($entity_type, $field, array($langcode)));
+    $langcode = field_language($entity_type, $entity, $field_name, $langcode);
 
     // Push the item as the single value for the field, and defer to
     // field_view_field() to build the render array for the whole field.
@@ -588,7 +586,10 @@ function field_view_field($entity_type, $entity, $field_name, $display = array()
 
     // Hook invocations are done through the _field_invoke() functions in
     // 'single field' mode, to reuse the language fallback logic.
-    $options = array('field_name' => $field_name, 'language' => field_multilingual_valid_language($langcode, FALSE));
+    // Determine the actual language to display for the field, given the
+    // languages available in the field data.
+    $display_language = field_language($entity_type, $entity, $field_name, $langcode);
+    $options = array('field_name' => $field_name, 'language' => $display_language);
     $null = NULL;
 
     // Invoke prepare_view steps if needed.
@@ -604,13 +605,12 @@ function field_view_field($entity_type, $entity, $field_name, $display = array()
     // Build the renderable array.
     $result = _field_invoke_default('view', $entity_type, $entity, $display, $null, $options);
 
-    // Invoke hook_field_attach_view_alter() to tet other modules alter the
+    // Invoke hook_field_attach_view_alter() to let other modules alter the
     // renderable array, as in a full field_attach_view() execution.
     $context = array(
       'obj_type' => $entity_type,
       'object' => $entity,
       'view_mode' => '_custom',
-      'langcode' => $langcode,
     );
     drupal_alter('field_attach_view', $result, $context);
 
@@ -623,6 +623,27 @@ function field_view_field($entity_type, $entity, $field_name, $display = array()
   return $output;
 }
 
+/**
+ * Returns the field items in the language they currently would be displayed.
+ *
+ * @param $entity_type
+ *   The type of $entity.
+ * @param $entity
+ *   The entity containing the data to be displayed.
+ * @param $field_name
+ *   The field to be displayed.
+ * @param $langcode
+ *   (optional) The language code $entity->{$field_name} has to be displayed in.
+ *   Defaults to the current language.
+ *
+ * @return
+ *   An array of field items keyed by delta if available, FALSE otherwise.
+ */
+function field_get_items($entity_type, $entity, $field_name, $langcode = NULL) {
+  $langcode = field_language($entity_type, $entity, $field_name, $langcode);
+  return isset($entity->{$field_name}[$langcode]) ? $entity->{$field_name}[$langcode] : FALSE;
+}
+
 /**
  * Determine whether a field has any data.
  *

modules/field/modules/field_sql_storage/field_sql_storage.module

@@ -311,7 +311,7 @@ function field_sql_storage_field_storage_load($entity_type, $entities, $age, $fi
       ->fields('t')
       ->condition('etid', $etid)
       ->condition($load_current ? 'entity_id' : 'revision_id', $ids, 'IN')
-      ->condition('language', field_multilingual_available_languages($entity_type, $field), 'IN')
+      ->condition('language', field_available_languages($entity_type, $field), 'IN')
       ->orderBy('delta');
 
     if (empty($options['deleted'])) {
@@ -356,7 +356,7 @@ function field_sql_storage_field_storage_write($entity_type, $entity, $op, $fiel
     $table_name = _field_sql_storage_tablename($field);
     $revision_name = _field_sql_storage_revision_tablename($field);
 
-    $all_languages = field_multilingual_available_languages($entity_type, $field);
+    $all_languages = field_available_languages($entity_type, $field);
     $field_languages = array_intersect($all_languages, array_keys((array) $entity->$field_name));
 
     // Delete and insert, rather than update, in case a value was added.

modules/field/tests/field_test.entity.inc

@@ -63,6 +63,19 @@ function field_test_entity_info_alter(&$entity_info) {
   }
 }
 
+/**
+ * Helper function to enable entity translations.
+ */
+function field_test_entity_info_translatable($entity_type = NULL, $translatable = NULL) {
+  drupal_static_reset('field_has_translation_handler');
+  $stored_value = &drupal_static(__FUNCTION__, array());
+  if (isset($entity_type)) {
+    $stored_value[$entity_type] = $translatable;
+    entity_info_cache_clear();
+  }
+  return $stored_value;
+}
+
 /**
  * Creates a new bundle for test_entity entities.
  *

modules/field/tests/field_test.module

@@ -87,27 +87,23 @@ function field_test_field_test_op_multiple($entity_type, $entities, $field, $ins
 }
 
 /**
- * Implements hook_field_languages().
+ * Implements hook_field_available_languages_alter().
  */
-function field_test_field_languages($entity_type, $field, &$languages) {
-  if ($field['settings']['test_hook_in']) {
+function field_test_field_available_languages_alter(&$languages, $context) {
+  if (variable_get('field_test_field_available_languages_alter', FALSE)) {
     // Add an unavailable language.
     $languages[] = 'xx';
     // Remove an available language.
-    unset($languages[0]);
+    $index = array_search('en', $languages);
+    unset($languages[$index]);
   }
 }
 
 /**
- * Helper function to enable entity translations.
+ * Implements hook_field_language_alter().
  */
-function field_test_entity_info_translatable($entity_type = NULL, $translatable = NULL) {
-  $stored_value = &drupal_static(__FUNCTION__, array());
-  if (isset($entity_type)) {
-    $stored_value[$entity_type] = $translatable;
-    entity_info_cache_clear();
-  }
-  return $stored_value;
+function field_test_field_language_alter(&$display_language, $context) {
+  locale_field_language_fallback($display_language, $context['entity'], $context['language']);
 }
 
 /**

modules/field/tests/field_test.storage.inc

@@ -95,7 +95,7 @@ function field_test_field_storage_load($entity_type, $entities, $age, $fields, $
     foreach ($field_data[$sub_table] as $row) {
       if ($row->type == $entity_type && (!$row->deleted || $options['deleted'])) {
         if (($load_current && in_array($row->entity_id, $ids)) || (!$load_current && in_array($row->revision_id, $ids))) {
-          if (in_array($row->language, field_multilingual_available_languages($entity_type, $field))) {
+          if (in_array($row->language, field_available_languages($entity_type, $field))) {
             if (!isset($delta_count[$row->entity_id][$row->language])) {
               $delta_count[$row->entity_id][$row->language] = 0;
             }
@@ -127,7 +127,7 @@ function field_test_field_storage_write($entity_type, $entity, $op, $fields) {
     $field_name = $field['field_name'];
     $field_data = &$data[$field_id];
 
-    $all_languages = field_multilingual_available_languages($entity_type, $field);
+    $all_languages = field_available_languages($entity_type, $field);
     $field_languages = array_intersect($all_languages, array_keys((array) $entity->$field_name));
 
     // Delete and insert, rather than update, in case a value was added.

modules/locale/locale.field.inc

-<?php
-// $Id$
-
-/**
- * @file
- * Field API multilingual handling.
- */
-
-/**
- * Form submit handler for node_form().
- *
- * Update the field language according to the node language, changing the
- * previous language if necessary.
- */
-function locale_field_node_form_update_field_language($form, &$form_state, $reset_previous = TRUE) {
-  $node = (object) $form_state['values'];
-  $available_languages = field_multilingual_content_languages();
-  // @todo: Unify language neutral language codes.
-  $selected_language = empty($node->language) ? LANGUAGE_NONE : $node->language;
-  list(, , $bundle) = entity_extract_ids('node', $node);
-
-  foreach (field_info_instances('node', $bundle) as $instance) {
-    $field_name = $instance['field_name'];
-    $field = field_info_field($field_name);
-    $previous_language = $form[$field_name]['#language'];
-
-    // Handle a possible language change: previous language values are deleted,
-    // new ones are inserted.
-    if ($field['translatable'] && $previous_language != $selected_language) {
-      $form_state['values'][$field_name][$selected_language] = $node->{$field_name}[$previous_language];
-      if ($reset_previous) {
-        $form_state['values'][$field_name][$previous_language] = array();
-      }
-    }
-  }
-}
-
-/**
- * Apply fallback rules to the given object.
- *
- * Parameters are the same of hook_field_attach_view().
- */
-function locale_field_fallback_view(&$output, $context) {
-  // Lazily init fallback values and candidates to avoid unnecessary calls.
-  $fallback_values = array();
-  $fallback_candidates = NULL;
-  list(, , $bundle) = entity_extract_ids($context['obj_type'], $context['object']);
-
-  foreach (field_info_instances($context['obj_type'], $bundle) as $instance) {
-    $field_name = $instance['field_name'];
-    $field = field_info_field($field_name);
-
-    // If the items array is empty then we have a missing field translation.
-    // @todo: Verify this assumption.
-    if (isset($output[$field_name]) && count(element_children($output[$field_name])) == 0) {
-      if (!isset($fallback_candidates)) {
-        require_once DRUPAL_ROOT . '/includes/language.inc';
-        $fallback_candidates = language_fallback_get_candidates();
-      }
-
-      foreach ($fallback_candidates as $langcode) {
-        // Again if we have a non-empty array we assume the field translation is
-        // valid.
-        if (!empty($context['object']->{$field_name}[$langcode])) {
-          // Cache fallback values per language as fields might have different
-          // fallback values.
-          if (!isset($fallback_values[$langcode])) {
-            $fallback_values[$langcode] = field_attach_view($context['obj_type'], $context['object'], $context['view_mode'], $langcode);
-          }
-          // We are done, skip to the next field.
-          $output[$field_name] = $fallback_values[$langcode][$field_name];
-          break;
-        }
-      }
-    }
-  }
-}

modules/locale/locale.info

@@ -6,7 +6,6 @@ version = VERSION
 core = 7.x
 files[] = locale.module
 files[] = locale.install
-files[] = locale.field.inc
 files[] = locale.admin.inc
 files[] = locale.test
 configure = admin/config/regional/language

modules/locale/locale.install

@@ -113,6 +113,7 @@ function locale_uninstall() {
   variable_del('locale_cache_strings');
   variable_del('locale_js_directory');
   variable_del('javascript_parsed');
+  variable_del('locale_field_language_fallback');
 
   foreach (language_types() as $type) {
     variable_del("language_negotiation_$type");

modules/locale/locale.module

@@ -410,13 +410,27 @@ function locale_form_alter(&$form, &$form_state, $form_id) {
 /**
  * Form submit handler for node_form().
  *
- * Check if Locale is registered as a translation handler and handle possible
+ * Checks if Locale is registered as a translation handler and handle possible
  * node language changes.
  */
 function locale_field_node_form_submit($form, &$form_state) {
-  if (field_multilingual_check_translation_handlers('node', 'locale')) {
-    module_load_include('inc', 'locale', 'locale.field');
-    locale_field_node_form_update_field_language($form, $form_state);
+  if (field_has_translation_handler('node', 'locale')) {
+    $node = (object) $form_state['values'];
+    $available_languages = field_content_languages();
+    list(, , $bundle) = entity_extract_ids('node', $node);
+
+    foreach (field_info_instances('node', $bundle) as $instance) {
+      $field_name = $instance['field_name'];
+      $field = field_info_field($field_name);
+      $previous_language = $form[$field_name]['#language'];
+
+      // Handle a possible language change: new language values are inserted,
+      // previous ones are deleted.
+      if ($field['translatable'] && $previous_language != $node->language) {
+        $form_state['values'][$field_name][$node->language] = $node->{$field_name}[$previous_language];
+        $form_state['values'][$field_name][$previous_language] = array();
+      }
+    }
   }
 }
 
@@ -438,20 +452,57 @@ function locale_theme() {
 }
 
 /**
- * Implements hook_field_attach_view_alter().
+ * Implements hook_field_language_alter().
  */
-function locale_field_attach_view_alter(&$output, $context) {
-  // In locale_field_fallback_view() we might call field_attach_view(). The
-  // static variable avoids unnecessary recursion.
-  static $recursion;
+function locale_field_language_alter(&$display_language, $context) {
+  // Do not apply core language fallback rules if they are disabled or if Locale
+  // is not registered as a translation handler.
+  if (variable_get('locale_field_language_fallback', TRUE) && field_has_translation_handler($context['entity_type'], 'locale')) {
+    locale_field_language_fallback($display_language, $context['entity'], $context['language']);
+  }
+}
 
-  // Do not apply fallback rules if disabled or if Locale is not registered as a
-  // translation handler.
-  if (!$recursion && variable_get('locale_field_fallback_view', TRUE) && field_multilingual_check_translation_handlers($context['obj_type'], 'locale')) {
-    $recursion = TRUE;
-    module_load_include('inc', 'locale', 'locale.field');
-    locale_field_fallback_view($output, $context);
-    $recursion = FALSE;
+/**
+ * Applies language fallback rules to the fields attached to the given entity.
+ *
+ * Core language fallback rules simply check if fields have a field translation
+ * for the requested language code. If so the requested language is returned,
+ * otherwise all the fallback candidates are inspected to see if there is a
+ * field translation available in another language.
+ * By default this is called by locale_field_language_alter(), but this
+ * behavior can be disabled by setting the 'locale_field_language_fallback'
+ * variable to FALSE.
+ *
+ * @param $display_language
+ *   A reference to an array of language codes keyed by field name.
+ * @param $entity
+ *   The entity to be displayed.
+ * @param $langcode
+ *   The language code $entity has to be displayed in. 
+ */
+function locale_field_language_fallback(&$display_language, $entity, $langcode) {
+  // Lazily init fallback candidates to avoid unnecessary calls.
+  $fallback_candidates = NULL;
+  $field_languages = array();
+
+  foreach ($display_language as $field_name => $field_language) {
+    // If the requested language is defined for the current field use it,
+    // otherwise search for a fallback value among the fallback candidates.
+    if (isset($entity->{$field_name}[$langcode])) {
+      $display_language[$field_name] = $langcode;
+    }
+    elseif (!empty($entity->{$field_name})) {
+      if (!isset($fallback_candidates)) {
+        require_once DRUPAL_ROOT . '/includes/language.inc';
+        $fallback_candidates = language_fallback_get_candidates();
+      }
+      foreach ($fallback_candidates as $fallback_language) {
+        if (isset($entity->{$field_name}[$fallback_language])) {
+          $display_language[$field_name] = $fallback_language;
+          break;
+        }
+      }
+    }
   }
 }