PHPLIB-160: implement drop() on bucket

src/GridFS/Bucket.php

@@ -150,6 +150,16 @@ class Bucket
         $gridFsStream->downloadToStream($destination);
     }
 
+    /**
+    * Drops the files and chunks collection associated with GridFS this bucket
+    *
+    */
+
+    public function drop()
+    {
+        $this->collectionsWrapper->dropCollections();
+    }
+
     /**
      * Find files from the GridFS bucket's files collection.
      *

src/GridFS/GridFSCollectionsWrapper.php

@@ -35,6 +35,11 @@ class GridFSCollectionsWrapper
         $this->chunksCollection = new Collection($manager, sprintf('%s.%s.chunks', $databaseName, $bucketName), $collectionOptions);
     }
 
+    public function dropCollections(){
+        $this->filesCollection-> drop();
+        $this->chunksCollection->drop();
+    }
+
     public function getChunksCollection()
     {
         return $this->chunksCollection;

tests/GridFS/BucketFunctionalTest.php

@@ -273,6 +273,13 @@ class BucketFunctionalTest extends FunctionalTestCase
 
         $this->assertEquals("testing", stream_get_contents($this->bucket->openDownloadStreamByName("second_name")));
     }
+    public function testDrop()
+    {
+        $id = $this->bucket->uploadFromStream("test_filename", $this->generateStream("hello world"));
+        $this->bucket->drop();
+        $id = $this->bucket->uploadFromStream("test_filename", $this->generateStream("hello world"));
+        $this->assertEquals(1, $this->collectionsWrapper->getFilesCollection()->count());
+    }
     /**
      *@dataProvider provideInsertChunks
      */