diff -r 47fac1692ede -r 9f70512ae2cf mercurial/pure/charencode.py
--- a/mercurial/pure/charencode.py	Sun Nov 10 07:30:14 2019 -0800
+++ b/mercurial/pure/charencode.py	Fri Nov 08 11:19:20 2019 -0800
@@ -85,6 +85,6 @@
         jm = _jsonmap
     # non-BMP char is represented as UTF-16 surrogate pair
     u16b = u8chars.decode('utf-8', _utf8strict).encode('utf-16', _utf8strict)
-    u16codes = array.array(r'H', u16b)
+    u16codes = array.array('H', u16b)
     u16codes.pop(0)  # drop BOM
     return b''.join(jm[x] if x < 128 else b'\\u%04x' % x for x in u16codes)