From: Eli Zaretskii <eliz@gnu.org>
Date: Sat, 8 Jan 2022 14:32:01 +0000 (+0200)
Subject: Fix Subject "simplification" in Rmail
X-Git-Tag: emacs-28.0.92~123
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=c54fda643d;p=emacs.git

Fix Subject "simplification" in Rmail

* lisp/mail/rmail.el (rmail-simplified-subject): Match against
"[external]" _after_ decoding the Subject by RFC-2047.
---

diff --git a/lisp/mail/rmail.el b/lisp/mail/rmail.el
index c598e67dab8..49eaeb560e0 100644
--- a/lisp/mail/rmail.el
+++ b/lisp/mail/rmail.el
@@ -3356,12 +3356,12 @@ removing prefixes such as Re:, Fwd: and so on and mailing list
 tags such as [tag]."
   (let ((subject (or (rmail-get-header "Subject" msgnum) ""))
 	(regexp "\\`[ \t\n]*\\(\\(\\w\\{1,4\\}\u00a0*[:：]\\|\\[[^]]+]\\)[ \t\n]+\\)*"))
+    (setq subject (rfc2047-decode-string subject))
     ;; Corporate mailing systems sometimes add `[External] :'; if that happened,
     ;; delete everything up thru there.  Empirically, that deletion makes
     ;; the Subject match the other messages in the thread.
     (if (string-match "\\[external][ \t\n]*:" subject)
         (setq subject (substring subject (match-end 0))))
-    (setq subject (rfc2047-decode-string subject))
     (setq subject (replace-regexp-in-string regexp "" subject))
     (replace-regexp-in-string "[ \t\n]+" " " subject)))