diff --git a/lib/files/mapper.php b/lib/files/mapper.php
index 2b6890472e3..15f5f0628b5 100644
--- a/lib/files/mapper.php
+++ b/lib/files/mapper.php
@@ -191,8 +191,8 @@ class Mapper
 
 		// apply index to file name
 		if ($index !== null) {
-			array_pop($sluggedElements);
-			array_push($sluggedElements, $filename.'-'.$index);
+			$last= array_pop($sluggedElements);
+			array_push($sluggedElements, $last.'-'.$index);
 		}
 
 		// add back the extension
diff --git a/tests/lib/files/mapper.php b/tests/lib/files/mapper.php
index 36221f8bcaa..79005eefdcb 100644
--- a/tests/lib/files/mapper.php
+++ b/tests/lib/files/mapper.php
@@ -34,8 +34,19 @@ class Mapper extends \PHPUnit_Framework_TestCase {
 	}
 
 	public function testSlugifyPath() {
+		// with extension
 		$this->assertEquals('D:/text.txt', $this->mapper->slugifyPath('D:/text.txt'));
 		$this->assertEquals('D:/text-2.txt', $this->mapper->slugifyPath('D:/text.txt', 2));
 		$this->assertEquals('D:/a/b/text.txt', $this->mapper->slugifyPath('D:/a/b/text.txt'));
+
+		// without extension
+		$this->assertEquals('D:/text', $this->mapper->slugifyPath('D:/text'));
+		$this->assertEquals('D:/text-2', $this->mapper->slugifyPath('D:/text', 2));
+		$this->assertEquals('D:/a/b/text', $this->mapper->slugifyPath('D:/a/b/text'));
+
+		// with double dot
+		$this->assertEquals('D:/text-text.txt', $this->mapper->slugifyPath('D:/text.text.txt'));
+		$this->assertEquals('D:/text-text-2.txt', $this->mapper->slugifyPath('D:/text.text.txt', 2));
+		$this->assertEquals('D:/a/b/text-text.txt', $this->mapper->slugifyPath('D:/a/b/text.text.txt'));
 	}
 }