diff --git a/tests/snippets/stdlib_os.py b/tests/snippets/stdlib_os.py
index 9a6ac72c2..525f35187 100644
--- a/tests/snippets/stdlib_os.py
+++ b/tests/snippets/stdlib_os.py
@@ -265,7 +265,7 @@ with TestWithTempDir() as tmpdir:
 	with TestWithTempCurrentDir():
 		os.chdir(tmpdir)
 		assert os.getcwd() == os.path.realpath(tmpdir)
-		os.path.exists(FILE_NAME)
+		assert os.path.exists(FILE_NAME)
 
 # supports
 assert isinstance(os.supports_fd, set)