yield 3-tuples for Message.Directory

adapt tuples to the same length and semantics as other messages

gallery_dl/extractor/4archive.py

@@ -38,7 +38,7 @@ class _4archiveThreadExtractor(Extractor):
         for post in posts:
             post.update(data)
             post["time"] = int(dt.to_ts(post["date"]))
-            yield Message.Directory, post
+            yield Message.Directory, "", post
             if "url" in post:
                 yield Message.Url, post["url"], text.nameext_from_url(
                     post["filename"], post)