- Patch #423888 by mikeryan, Crell, drunken monkey: use subqueries for ->countQuery(), at least for MySQL.

includes/database/select.inc

@@ -93,6 +93,24 @@ interface SelectQueryInterface extends QueryConditionInterface, QueryAlterableIn
    */
   public function &getOrderBy();
 
+  /**
+   * Returns a reference to the group-by array for this query.
+   *
+   * Because this method returns by reference, alter hooks may edit the group-by
+   * array directly to make their changes. If just adding additional grouping
+   * fields, however, the use of groupBy() is preferred.
+   *
+   * Note that this method must be called by reference as well:
+   *
+   * @code
+   * $fields =& $query->getGroupBy();
+   * @endcode
+   *
+   * @return
+   *   A reference to the group-by array structure.
+   */
+  public function &getGroupBy();
+
   /**
    * Returns a reference to the tables array for this query.
    *
@@ -619,6 +637,10 @@ class SelectQueryExtender implements SelectQueryInterface {
     return $this->query->getOrderBy();
   }
 
+  public function &getGroupBy() {
+    return $this->query->getGroupBy();
+  }
+
   public function &getTables() {
     return $this->query->getTables();
   }
@@ -1026,6 +1048,10 @@ class SelectQuery extends Query implements SelectQueryInterface {
     return $this->order;
   }
 
+  public function &getGroupBy() {
+    return $this->group;
+  }
+
   public function &getTables() {
     return $this->tables;
   }
@@ -1279,13 +1305,24 @@ class SelectQuery extends Query implements SelectQueryInterface {
     // Create our new query object that we will mutate into a count query.
     $count = clone($this);
 
+    $group_by = array_keys($count->getGroupBy());
+
     if (!$count->distinct) {
       // When not executing a distinct query, we can zero-out existing fields
-      // and expressions.
+      // and expressions that are not used by a GROUP BY.  Fields listed in
+      // the GROUP BY clause need to be present in the query.
       $fields =& $count->getFields();
-      $fields = array();
+      foreach (array_keys($fields) as $field) {
+        if (!empty($group_by[$field])) {
+          unset($fields[$field]);
+        }
+      }
       $expressions =& $count->getExpressions();
-      $expressions = array();
+      foreach (array_keys($expressions) as $field) {
+        if (!empty($group_by[$field])) {
+          unset($fields[$field]);
+        }
+      }
 
       // Also remove 'all_fields' statements, which are expanded into tablename.*
       // when the query is executed.
@@ -1294,22 +1331,25 @@ class SelectQuery extends Query implements SelectQueryInterface {
       }
     }
 
+    // If we've just removed all fields from the query, make sure there is at
+    // least one so that the query still runs.
+    $count->addExpression('1');
+
     // Ordering a count query is a waste of cycles, and breaks on some
     // databases anyway.
     $orders = &$count->getOrderBy();
     $orders = array();
 
-    if ($count->distinct) {
+    if ($count->distinct && !empty($group_by)) {
-      // If the query is distinct, we need to execute it in a subquery,
+      // If the query is distinct and contains a GROUP BY, we need to remove the
-      // because SQL99 does not support counting on distinct multiple fields.
+      // distinct because SQL99 does not support counting on distinct multiple fields.
-      $count = db_select($count);
       $count->distinct = FALSE;
     }
 
-    // COUNT() is an expression, so we add that back in.
+    $query = db_select($count);
-    $count->addExpression('COUNT(*)');
+    $query->addExpression('COUNT(*)');
 
-    return $count;
+    return $query;
   }
 
   public function __toString() {

modules/field/field.multilingual.inc

@@ -216,10 +216,11 @@ function field_language($entity_type, $entity, $field_name = NULL, $langcode = N
   if (!isset($display_languages[$entity_type][$id][$langcode])) {
     $display_language = array();
 
-    // By default display language is set to LANGUAGE_NONE. It is up to
+    // By default display language is set to LANGUAGE_NONE if the field
-    // translation handlers to implement language fallback rules.
+    // translation is not available. It is up to translation handlers to
+    // implement language fallback rules.
     foreach (field_info_instances($entity_type, $bundle) as $instance) {
-      $display_language[$instance['field_name']] = LANGUAGE_NONE;
+      $display_language[$instance['field_name']] = isset($entity->{$instance['field_name']}[$langcode]) ? $langcode : LANGUAGE_NONE;
     }
 
     if (field_has_translation_handler($entity_type)) {

modules/field/tests/field.test

@@ -2639,8 +2639,7 @@ class FieldTranslationsTestCase extends FieldTestCase {
     field_create_instance($instance);
 
     $entity = field_test_create_stub_entity(1, 1, $this->instance['bundle']);
-    list(, , $bundle) = entity_extract_ids($entity_type, $entity);
+    $instances = field_info_instances($entity_type, $this->instance['bundle']);
-    $instances = field_info_instances($entity_type, $bundle);
 
     $enabled_languages = field_content_languages();
     $languages = array();
@@ -2688,6 +2687,13 @@ class FieldTranslationsTestCase extends FieldTestCase {
     drupal_static_reset('field_language');
     $langcode = field_language($entity_type, $entity, $this->field_name, $requested_language);
     $this->assertTrue(isset($entity->{$this->field_name}[$langcode]) && $langcode != $requested_language, t('The display language for the (single) field %field_name is %language.', array('%field_name' => $field_name, '%language' => $langcode)));
+
+    // Test field_language() basic behavior without language fallback.
+    variable_set('field_test_language_fallback', FALSE);
+    $entity->{$this->field_name}[$requested_language] = mt_rand(1, 127);
+    drupal_static_reset('field_language');
+    $display_language = field_language($entity_type, $entity, $this->field_name, $requested_language);
+    $this->assertEqual($display_language, $requested_language, t('Display language behave correctly when language fallback is disabled'));
   }
 
   /**

modules/field/tests/field_test.module

@@ -103,7 +103,9 @@ function field_test_field_available_languages_alter(&$languages, $context) {
  * Implements hook_field_language_alter().
  */
 function field_test_field_language_alter(&$display_language, $context) {
-  locale_field_language_fallback($display_language, $context['entity'], $context['language']);
+  if (variable_get('field_test_language_fallback', TRUE)) {
+    locale_field_language_fallback($display_language, $context['entity'], $context['language']);
+  }
 }
 
 /**

modules/simpletest/tests/database_test.test

@@ -1986,6 +1986,19 @@ class DatabaseSelectComplexTestCase extends DatabaseTestCase {
     $this->assertEqual($count, 6, t('Counted the correct number of records.'));
   }
 
+  /**
+   * Test that we can generate a count query from a query with GROUP BY.
+   */
+  function testCountQueryGroupBy() {
+    $query = db_select('test_task');
+    $pid_field = $query->addField('test_task', 'pid');
+    $query->groupBy('pid');
+
+    $count = $query->countQuery()->execute()->fetchField();
+
+    $this->assertEqual($count, 3, t('Counted the correct number of records.'));
+  }
+
   /**
    * Confirm that we can properly nest conditional clauses.
    */