test_ast: pass the filename to ast.parse()
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 8e105b2..c45326f 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -947,7 +947,7 @@
             fn = os.path.join(stdlib, module)
             with open(fn, "r", encoding="utf-8") as fp:
                 source = fp.read()
-            mod = ast.parse(source)
+            mod = ast.parse(source, fn)
             compile(mod, fn, "exec")