Fix message-subject-re-regexp some more

1 files changed, 25 insertions, 12 deletions

diff --git a/.gnus b/.gnus
index 18873aa..8bca6a2 100644
--- a/.gnus
+++ b/.gnus
@@ -41,18 +41,31 @@
                                      . "%b %d")
                                     (t
                                      . "%F"))
-      gnus-gcc-mark-as-read t
-      ;; This regexp is used both in Gnus summary buffers to detect
-      ;; and elide similar subjects in a thread, and by message mode
-      ;; when replying, to determine what to strip from the subject.
-      message-subject-re-regexp
-      (rx bol (+ (* space)
-                 (or "re" "Re" "RE"
-                     "aw" "Aw" "AW"
-                     "sv" "Sv" "SV"
-                     (seq "bug#" (+ digit))
-                     "[External]")
-                 (* space) ":" (* space))))
+      gnus-gcc-mark-as-read t)
+
+;; message-subject-re-regexp is used both in Gnus summary buffers to
+;; detect and elide similar subjects in a thread, and by message mode
+;; when replying, to determine what to strip from the subject.
+;;
+;; Some MUAs add cruft to the subject, turning "Re: bug#123: foobar"
+;; into "RE: [External] : Re: bug#1234: foobar", which Debbugs will
+;; then turn into "bug#1234: [External] : Re: bug#1234: foobar".
+;;
+;; The only way I can find to tell the Gnus summary code to
+;; canonicalize all that cruft away is by tweaking this regexp, but
+;; setting its global value causes message mode to elide stuff it
+;; shouldn't.  Therefore, chase down the best Gnus hook for the job,
+;; and set the regexp locally.
+(add-hook 'gnus-summary-generate-hook
+          (lambda ()
+            (setq-local message-subject-re-regexp
+                        (rx bol (+ (* space)
+                                   (or "re" "Re" "RE"
+                                       "aw" "Aw" "AW"
+                                       "sv" "Sv" "SV"
+                                       (seq "bug#" (+ digit))
+                                       "[External]")
+                                   (* space) ":" (* space))))))
 
 (gnus-add-configuration
  '(summary