PHPLIB-414: Remove orphan chunks for GridFS spec tests

tests/GridFS/SpecFunctionalTest.php

@@ -6,6 +6,7 @@ use MongoDB\Collection;
 use MongoDB\BSON\Binary;
 use MongoDB\BSON\ObjectId;
 use MongoDB\BSON\UTCDateTime;
+use MongoDB\GridFS\Exception\FileNotFoundException;
 use MongoDB\Operation\BulkWrite;
 use DateTime;
 use Exception;
@@ -54,6 +55,15 @@ class SpecFunctionalTest extends FunctionalTestCase
             $result = $e;
         }
 
+        /* Per the GridFS spec: "Drivers MAY attempt to delete any orphaned
+         * chunks with files_id equal to id before raising the error." The spec
+         * tests do not expect orphaned chunks to be removed, so we manually
+         * remove those chunks from the expected collection. */
+        if ($test['act']['operation'] === 'delete' && $result instanceof FileNotFoundException) {
+            $filesId = $this->convertTypes($test['act'])['arguments']['id'];
+            $this->expectedChunksCollection->deleteMany(['files_id' => $filesId]);
+        }
+
         if (isset($test['assert'])) {
             $this->executeAssert($test['assert'], $result);
         }