Reset prefetch iterator if prefetch or query settings are changed (#219)

library/Solarium/Plugin/PrefetchIterator.php

@@ -104,6 +104,7 @@ class PrefetchIterator extends Plugin implements \Iterator, \Countable
      */
     public function setPrefetch($value)
     {
+        $this->resetData();
         return $this->setOption('prefetch', $value);
     }
 
@@ -126,6 +127,7 @@ class PrefetchIterator extends Plugin implements \Iterator, \Countable
     public function setQuery($query)
     {
         $this->query = $query;
+        $this->resetData();
 
         return $this;
     }
@@ -225,4 +227,15 @@ class PrefetchIterator extends Plugin implements \Iterator, \Countable
         $this->documents = $this->result->getDocuments();
         $this->start += $this->getPrefetch();
     }
+
+    /**
+     * Reset any cached data / position
+     */
+    protected function resetData()
+    {
+        $this->position = null;
+        $this->result = null;
+        $this->documents = null;
+        $this->start = 0;
+    }
 }

tests/Solarium/Tests/Plugin/PrefetchIteratorTest.php

@@ -90,6 +90,8 @@ class PrefetchIteratorTest extends \PHPUnit_Framework_TestCase
     {
         $result = $this->getResult();
         $mockClient = $this->getMock('Solarium\Core\Client\Client', array('execute'));
+
+        // Important: if prefetch or query settings are not changed, the query should be executed only once!
         $mockClient->expects($this->exactly(1))->method('execute')->will($this->returnValue($result));
 
         $this->plugin->initPlugin($mockClient, array());
@@ -110,6 +112,58 @@ class PrefetchIteratorTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals($result->getDocuments(), $results2);
     }
 
+    public function testIteratorResetOnSetPrefetch()
+    {
+        $result = $this->getResult();
+        $mockClient = $this->getMock('Solarium\Core\Client\Client', array('execute'));
+        $mockClient->expects($this->exactly(2))->method('execute')->will($this->returnValue($result));
+
+        $this->plugin->initPlugin($mockClient, array());
+        $this->plugin->setQuery($this->query);
+
+        $results1 = array();
+        foreach ($this->plugin as $doc) {
+            $results1[] = $doc;
+        }
+
+        $this->plugin->setPrefetch(1000);
+
+        // the second foreach should trigger a reset and a second query execution (checked by mock)
+        $results2 = array();
+        foreach ($this->plugin as $doc) {
+            $results2[] = $doc;
+        }
+
+        $this->assertEquals($result->getDocuments(), $results1);
+        $this->assertEquals($result->getDocuments(), $results2);
+    }
+
+    public function testIteratorResetOnSetQuery()
+    {
+        $result = $this->getResult();
+        $mockClient = $this->getMock('Solarium\Core\Client\Client', array('execute'));
+        $mockClient->expects($this->exactly(2))->method('execute')->will($this->returnValue($result));
+
+        $this->plugin->initPlugin($mockClient, array());
+        $this->plugin->setQuery($this->query);
+
+        $results1 = array();
+        foreach ($this->plugin as $doc) {
+            $results1[] = $doc;
+        }
+
+        $this->plugin->setQuery($this->query);
+
+        // the second foreach should trigger a reset and a second query execution (checked by mock)
+        $results2 = array();
+        foreach ($this->plugin as $doc) {
+            $results2[] = $doc;
+        }
+
+        $this->assertEquals($result->getDocuments(), $results1);
+        $this->assertEquals($result->getDocuments(), $results2);
+    }
+
     public function getResult()
     {
         $numFound = 5;