diff -r 06080afd0565 -r c04e0836f039 mercurial/commands.py
--- a/mercurial/commands.py	Sun Sep 15 22:43:32 2019 +0900
+++ b/mercurial/commands.py	Tue Sep 17 10:47:31 2019 +0000
@@ -514,6 +514,7 @@
     :``tar``:   tar archive, uncompressed
     :``tbz2``:  tar archive, compressed using bzip2
     :``tgz``:   tar archive, compressed using gzip
+    :``txz``:   tar archive, compressed using lzma (only in Python 3)
     :``uzip``:  zip archive, uncompressed
     :``zip``:   zip archive, compressed using deflate