From 8a47b2342e53c9cdf3093982486b19d6cc2f3e9b Mon Sep 17 00:00:00 2001
From: Steve Clay <steve@mrclay.org>
Date: Sat, 8 Jun 2013 21:34:11 -0400
Subject: Improved algorithm by tracking total incomplete entities

---
 engine/classes/ElggBatch.php | 18 ++++++++++++------
 engine/tests/api/helpers.php | 16 ++++++++--------
 2 files changed, 20 insertions(+), 14 deletions(-)

(limited to 'engine')

diff --git a/engine/classes/ElggBatch.php b/engine/classes/ElggBatch.php
index ac79cf084..d810ea066 100644
--- a/engine/classes/ElggBatch.php
+++ b/engine/classes/ElggBatch.php
@@ -156,6 +156,13 @@ class ElggBatch
 	 */
 	private $incompleteEntities = array();
 
+	/**
+	 * Total number of incomplete entities fetched
+	 *
+	 * @var int
+	 */
+	private $totalIncompletes = 0;
+
 	/**
 	 * Batches operations on any elgg_get_*() or compatible function that supports
 	 * an options array.
@@ -242,12 +249,9 @@ class ElggBatch
 	/**
 	 * Fetches the next chunk of results
 	 *
-	 * @param int $num_incompletes_last_fetch When called recursively, this is the number of
-	 *                                        incomplete entities returned in the last fetch.
-	 *
 	 * @return bool
 	 */
-	private function getNextResultsChunk($num_incompletes_last_fetch = 0) {
+	private function getNextResultsChunk() {
 
 		// always reset results.
 		$this->results = array();
@@ -281,7 +285,7 @@ class ElggBatch
 		if ($this->incrementOffset) {
 			$offset = $this->offset + $this->retrievedResults;
 		} else {
-			$offset = $this->offset + $num_incompletes_last_fetch;
+			$offset = $this->offset + $this->totalIncompletes;
 		}
 
 		$current_options = array(
@@ -298,6 +302,8 @@ class ElggBatch
 		$num_results = count($this->results);
 		$num_incomplete = count($this->incompleteEntities);
 
+		$this->totalIncompletes += $num_incomplete;
+
 		if ($this->incompleteEntities) {
 			// pad the front of the results with nulls representing the incompletes
 			array_splice($this->results, 0, 0, array_pad(array(), $num_incomplete, null));
@@ -318,7 +324,7 @@ class ElggBatch
 			if ($num_results == 0) {
 				// This fetch was *all* incompletes! We need to fetch until we can either
 				// offer at least one row to iterate over, or give up.
-				return $this->getNextResultsChunk($num_incomplete);
+				return $this->getNextResultsChunk();
 			}
 			return true;
 		} else {
diff --git a/engine/tests/api/helpers.php b/engine/tests/api/helpers.php
index 06ef55138..10216140f 100644
--- a/engine/tests/api/helpers.php
+++ b/engine/tests/api/helpers.php
@@ -579,7 +579,7 @@ class ElggCoreHelpersTest extends ElggCoreUnitTest {
 	}
 
 	public function testElggBatchReadHandlesBrokenEntities() {
-		$num_test_entities = 6;
+		$num_test_entities = 8;
 		$guids = array();
 		for ($i = $num_test_entities; $i > 0; $i--) {
 			$entity = new ElggObject();
@@ -592,11 +592,11 @@ class ElggCoreHelpersTest extends ElggCoreUnitTest {
 		}
 
 		// break entities such that the first fetch has one incomplete
-		// and the second fetch has only incompletes!
+		// and the second and third fetches have only incompletes!
 		$db_prefix = elgg_get_config('dbprefix');
 		delete_data("
 			DELETE FROM {$db_prefix}objects_entity
-			WHERE guid IN ({$guids[1]}, {$guids[2]}, {$guids[3]})
+			WHERE guid IN ({$guids[1]}, {$guids[2]}, {$guids[3]}, {$guids[4]}, {$guids[5]})
 		");
 
 		$options = array(
@@ -613,7 +613,7 @@ class ElggCoreHelpersTest extends ElggCoreUnitTest {
 		}
 
 		// The broken entities should not have been visited
-		$this->assertEqual($entities_visited, array($guids[0], $guids[4], $guids[5]));
+		$this->assertEqual($entities_visited, array($guids[0], $guids[6], $guids[7]));
 
 		// cleanup (including leftovers from previous tests)
 		$entity_rows = elgg_get_entities(array_merge($options, array(
@@ -629,7 +629,7 @@ class ElggCoreHelpersTest extends ElggCoreUnitTest {
 	}
 
 	public function testElggBatchDeleteHandlesBrokenEntities() {
-		$num_test_entities = 6;
+		$num_test_entities = 8;
 		$guids = array();
 		for ($i = $num_test_entities; $i > 0; $i--) {
 			$entity = new ElggObject();
@@ -642,11 +642,11 @@ class ElggCoreHelpersTest extends ElggCoreUnitTest {
 		}
 
 		// break entities such that the first fetch has one incomplete
-		// and the second fetch has only incompletes!
+		// and the second and third fetches have only incompletes!
 		$db_prefix = elgg_get_config('dbprefix');
 		delete_data("
 			DELETE FROM {$db_prefix}objects_entity
-			WHERE guid IN ({$guids[1]}, {$guids[2]}, {$guids[3]})
+			WHERE guid IN ({$guids[1]}, {$guids[2]}, {$guids[3]}, {$guids[4]}, {$guids[5]})
 		");
 
 		$options = array(
@@ -664,7 +664,7 @@ class ElggCoreHelpersTest extends ElggCoreUnitTest {
 		}
 
 		// The broken entities should not have been visited
-		$this->assertEqual($entities_visited, array($guids[0], $guids[4], $guids[5]));
+		$this->assertEqual($entities_visited, array($guids[0], $guids[6], $guids[7]));
 
 		// cleanup (including leftovers from previous tests)
 		$entity_rows = elgg_get_entities(array_merge($options, array(
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