From 41d41c91a8c5e7734f6ec450b602c60b40c5f1f7 Mon Sep 17 00:00:00 2001
From: Tim Otten <totten@civicrm.org>
Date: Fri, 29 Jun 2018 13:58:11 -0700
Subject: [PATCH] (dev/core#217) CRM_Core_DAO - Add a helper which returns
 results in generator format

---
 CRM/Core/DAO.php                   | 23 +++++++++++++++++++++++
 tests/phpunit/CRM/Core/DAOTest.php | 28 ++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/CRM/Core/DAO.php b/CRM/Core/DAO.php
index b4d07e75ad..3416e61a70 100644
--- a/CRM/Core/DAO.php
+++ b/CRM/Core/DAO.php
@@ -1114,6 +1114,29 @@ FROM   civicrm_domain
     return $result;
   }
 
+  /**
+   * Return the results as PHP generator.
+   *
+   * @param string $type
+   *   Whether the generator yields 'dao' objects or 'array's.
+   */
+  public function fetchGenerator($type = 'dao') {
+    while ($this->fetch()) {
+      switch ($type) {
+        case 'dao':
+          yield $this;
+          break;
+
+        case 'array':
+          yield $this->toArray();
+          break;
+
+        default:
+          throw new \RuntimeException("Invalid record type ($type)");
+      }
+    }
+  }
+
   /**
    * Returns a singular value.
    *
diff --git a/tests/phpunit/CRM/Core/DAOTest.php b/tests/phpunit/CRM/Core/DAOTest.php
index 9cf423c73a..2d362709f7 100644
--- a/tests/phpunit/CRM/Core/DAOTest.php
+++ b/tests/phpunit/CRM/Core/DAOTest.php
@@ -422,6 +422,34 @@ class CRM_Core_DAOTest extends CiviUnitTestCase {
     return $constants;
   }
 
+  public function testFetchGeneratorDao() {
+    $this->individualCreate([], 0);
+    $this->individualCreate([], 1);
+    $this->individualCreate([], 2);
+    $count = 0;
+    $g = CRM_Core_DAO::executeQuery('SELECT contact_type FROM civicrm_contact WHERE contact_type = "Individual" LIMIT 3')
+      ->fetchGenerator();
+    foreach ($g as $row) {
+      $this->assertEquals('Individual', $row->contact_type);
+      $count++;
+    }
+    $this->assertEquals(3, $count);
+  }
+
+  public function testFetchGeneratorArray() {
+    $this->individualCreate([], 0);
+    $this->individualCreate([], 1);
+    $this->individualCreate([], 2);
+    $count = 0;
+    $g = CRM_Core_DAO::executeQuery('SELECT contact_type FROM civicrm_contact WHERE contact_type = "Individual" LIMIT 3')
+      ->fetchGenerator('array');
+    foreach ($g as $row) {
+      $this->assertEquals('Individual', $row['contact_type']);
+      $count++;
+    }
+    $this->assertEquals(3, $count);
+  }
+
   /**
    * @dataProvider serializationMethods
    */
-- 
2.25.1