Issue #1828790 by plach, chx, pfrenssen: Fixed Entity count query not working with fields shared among different entity types.

core/modules/field/modules/field_sql_storage/lib/Drupal/field_sql_storage/Entity/Query.php

@@ -69,6 +69,7 @@ class Query extends QueryBase {
     $entity_tables[$base_table] = drupal_get_schema($base_table);
     $sqlQuery = $this->connection->select($base_table, 'base_table', array('conjunction' => $this->conjunction));
     $sqlQuery->addMetaData('configurable_fields', $configurable_fields);
+    $sqlQuery->addMetaData('entity_type', $entity_type);
     // Determines the key of the column to join on. This is either the entity
     // id key or the revision id key, depending on whether the entity type
     // supports revisions.

core/modules/field/modules/field_sql_storage/lib/Drupal/field_sql_storage/Entity/Tables.php

@@ -129,7 +129,8 @@ class Tables {
       if ($field['cardinality'] != 1) {
         $this->sqlQuery->addMetaData('simple_query', FALSE);
       }
-      $this->fieldTables[$field_name] = $this->addJoin($type, $table, "%alias.$field_id_field = base_table.$entity_id_field", $langcode);
+      $entity_type = $this->sqlQuery->getMetaData('entity_type');
+      $this->fieldTables[$field_name] = $this->addJoin($type, $table, "%alias.$field_id_field = base_table.$entity_id_field AND %alias.entity_type = '$entity_type'", $langcode);
     }
     return $this->fieldTables[$field_name];
   }

core/modules/system/lib/Drupal/system/Tests/Entity/EntityQueryTest.php

@@ -367,6 +367,37 @@ class EntityQueryTest extends WebTestBase {
     $this->assertResult(range(15, 1));
   }
 
+  /**
+   * Test entity count query.
+   */
+  protected function testCount() {
+    // Attach the existing 'figures' field to a second entity type so that we
+    // can test whether cross entity type fields produce the correct query.
+    $field_name = $this->figures;
+    $bundle = $this->randomName();
+    $instance = array(
+      'field_name' => $field_name,
+      'entity_type' => 'test_entity_bundle',
+      'bundle' => $bundle,
+    );
+    field_create_instance($instance);
+
+    $entity = entity_create('test_entity_bundle', array(
+      'ftid' => 1,
+      'fttype' => $bundle,
+    ));
+    $entity->enforceIsNew();
+    $entity->setNewRevision();
+    $entity->save();
+    // As the single entity of this type we just saved does not have a value
+    // in the color field, the result should be 0.
+    $count = $this->factory->get('test_entity_bundle')
+      ->exists("$field_name.color")
+      ->count()
+      ->execute();
+     $this->assertFalse($count);
+  }
+
   protected function assertResult() {
     $assert = array();
     $expected = func_get_args();