emacs: Prefer '[No Subject]' to blank subjects.

[notmuch] / emacs / notmuch-wash.el

diff --git a/emacs/notmuch-wash.el b/emacs/notmuch-wash.el
index 1f420b25a05d770556cd19e4e737f522b7e18098..67143e5310d35ae87adb2b3e076571e0a154559a 100644 (file)
--- a/emacs/notmuch-wash.el
+++ b/emacs/notmuch-wash.el
@@ -290,6 +290,44 @@ When doing so, maintaining citation leaders in the wrapped text."
 
 (defvar diff-file-header-re) ; From `diff-mode.el'.
 
+(defun notmuch-wash-subject-to-filename (subject &optional maxlen)
+  "Convert a mail SUBJECT into a filename.
+
+The resulting filename is similar to the names generated by \"git
+format-patch\", without the leading patch sequence number
+\"0001-\" and \".patch\" extension. Any leading \"[PREFIX]\"
+style strings are removed prior to conversion.
+
+Optional argument MAXLEN is the maximum length of the resulting
+filename, before trimming any trailing . and - characters."
+  (let* ((s (replace-regexp-in-string "^ *\\(\\[[^]]*\\] *\\)*" "" subject))
+        (s (replace-regexp-in-string "[^A-Za-z0-9._]+" "-" s))
+        (s (replace-regexp-in-string "\\.+" "." s))
+        (s (if maxlen (substring s 0 (min (length s) maxlen)) s))
+        (s (replace-regexp-in-string "[.-]*$" "" s)))
+    s))
+
+(defun notmuch-wash-subject-to-patch-sequence-number (subject)
+  "Convert a patch mail SUBJECT into a patch sequence number.
+
+Return the patch sequence number N from the last \"[PATCH N/M]\"
+style prefix in SUBJECT, or nil if such a prefix can't be found."
+  (when (string-match
+        "^ *\\(\\[[^]]*\\] *\\)*\\[[^]]*?\\([0-9]+\\)/[0-9]+[^]]*\\].*"
+        subject)
+      (string-to-number (substring subject (match-beginning 2) (match-end 2)))))
+
+(defun notmuch-wash-subject-to-patch-filename (subject)
+  "Convert a patch mail SUBJECT into a filename.
+
+The resulting filename is similar to the names generated by \"git
+format-patch\". If the patch mail was generated and sent using
+\"git format-patch/send-email\", this should re-create the
+original filename the sender had."
+  (format "%04d-%s.patch"
+         (or (notmuch-wash-subject-to-patch-sequence-number subject) 1)
+         (notmuch-wash-subject-to-filename subject 52)))
+
 (defun notmuch-wash-convert-inline-patch-to-part (msg depth)
   "Convert an inline patch into a fake 'text/x-diff' attachment.
 
@@ -298,27 +336,29 @@ patch and then guesses the extent of the patch, there is scope
 for error."
 
   (goto-char (point-min))
-  (if (re-search-forward diff-file-header-re nil t)
-      (progn
-       (beginning-of-line -1)
-       (let ((patch-start (point))
-             (patch-end (point-max))
-             part)
-         (goto-char patch-start)
-         (if (or
-              ;; Patch ends with signature.
-              (re-search-forward notmuch-wash-signature-regexp nil t)
-              ;; Patch ends with bugtraq comment.
-              (re-search-forward "^\\*\\*\\* " nil t))
-             (setq patch-end (match-beginning 0)))
-         (save-restriction
-           (narrow-to-region patch-start patch-end)
-           (setq part (plist-put part :content-type "text/x-diff"))
-           (setq part (plist-put part :content (buffer-string)))
-           (setq part (plist-put part :id -1))
-           (setq part (plist-put part :filename "inline patch"))
-           (delete-region (point-min) (point-max))
-           (notmuch-show-insert-bodypart nil part depth))))))
+  (when (re-search-forward diff-file-header-re nil t)
+    (beginning-of-line -1)
+    (let ((patch-start (point))
+         (patch-end (point-max))
+         part)
+      (goto-char patch-start)
+      (if (or
+          ;; Patch ends with signature.
+          (re-search-forward notmuch-wash-signature-regexp nil t)
+          ;; Patch ends with bugtraq comment.
+          (re-search-forward "^\\*\\*\\* " nil t))
+         (setq patch-end (match-beginning 0)))
+      (save-restriction
+       (narrow-to-region patch-start patch-end)
+       (setq part (plist-put part :content-type "inline-patch-fake-part"))
+       (setq part (plist-put part :content (buffer-string)))
+       (setq part (plist-put part :id -1))
+       (setq part (plist-put part :filename
+                             (notmuch-wash-subject-to-patch-filename
+                              (plist-get
+                               (plist-get msg :headers) :Subject))))
+       (delete-region (point-min) (point-max))
+       (notmuch-show-insert-bodypart nil part depth)))))
 
 ;;