diff --git a/lib/private/Files/Cache/Cache.php b/lib/private/Files/Cache/Cache.php
index 1cb11c70a4061927ad3ded1a25424faf573c04e3..43e48e51654c903e5f3b93ab0896d055907ea2d2 100644
--- a/lib/private/Files/Cache/Cache.php
+++ b/lib/private/Files/Cache/Cache.php
@@ -150,6 +150,8 @@ class Cache implements ICache {
 				$data = $this->partial[$file];
 			}
 			return $data;
+		} else if (!$data) {
+			return $data;
 		} else {
 			return self::cacheEntryFromData($data, $this->mimetypeLoader);
 		}
diff --git a/tests/lib/Files/Cache/CacheTest.php b/tests/lib/Files/Cache/CacheTest.php
index bc95a9004f8bfcf7facea5c3618ea69a77a545cf..d984964ca9f0ca17d4b5dc7b56ddfcb3d8802a0c 100644
--- a/tests/lib/Files/Cache/CacheTest.php
+++ b/tests/lib/Files/Cache/CacheTest.php
@@ -553,6 +553,7 @@ class CacheTest extends \Test\TestCase {
 
 	function testNonExisting() {
 		$this->assertFalse($this->cache->get('foo.txt'));
+		$this->assertFalse($this->cache->get(-1));
 		$this->assertEquals(array(), $this->cache->getFolderContents('foo'));
 	}