#7612 Restore the tmp folder

.gitignore

@@ -28,7 +28,8 @@ php_errors.log
 /plugins/*/tests/UI/screenshot-diffs
 /plugins/*/Test/UI/screenshot-diffs
 /robots.txt
-/tmp/
+/tmp/*
+!/tmp/.gitkeep
 /vendor/
 /.cache
 /.externalToolBuilders

tests/PHPUnit/Integration/ReleaseCheckListTest.php

@@ -300,6 +300,11 @@ class ReleaseCheckListTest extends \PHPUnit_Framework_TestCase
         $this->assertTrue(preg_match($pattern, $contents) == 0);
     }
 
+    public function testTmpDirectoryContainsGitKeep()
+    {
+        $this->assertFileExists(PIWIK_DOCUMENT_ROOT . '/tmp/.gitkeep');
+    }
+
     private function checkFilesAreInPngFormat($files)
     {
         $this->checkFilesAreInFormat($files, "png");