emacs/show: Make the insertion of part headers overridable.

[notmuch] / emacs / notmuch-show.el

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 9d9c89fcf834dc724e6c670ab539a4f444450050..ddb9c65c6d05c43319df0e08752f0f44bbdcffc9 100644 (file)
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -930,13 +930,23 @@ will return nil if the CID is unknown or cannot be retrieved."
             "text/x-diff")
        content-type)))
 
+;; The following variable can be overridden by let bindings.
+(defvar notmuch-show-insert-header-p-function 'notmuch-show-insert-header-p
+  "Specify which function decides which part headers get inserted.
+
+The function should take two parameters, PART and HIDE, and
+should return non-NIL if a header button should be inserted for
+this part.")
+
 (defun notmuch-show-insert-header-p (part hide)
-  "Return non-NIL if a header button should be inserted for this part."
   ;; Show all part buttons except for the first part if it is text/plain.
   (let ((mime-type (notmuch-show-mime-type part)))
     (not (and (string= mime-type "text/plain")
              (<= (plist-get part :id) 1)))))
 
+(defun notmuch-show-reply-insert-header-p-never (part hide)
+  nil)
+
 (defun notmuch-show-insert-bodypart (msg part depth &optional hide)
   "Insert the body part PART at depth DEPTH in the current thread.
 
@@ -953,10 +963,10 @@ useful for quoting in replies)."
                    (> notmuch-show-max-text-part-size 0)
                    (> (length (plist-get part :content)) notmuch-show-max-text-part-size)))
         (beg (point))
-        ;; We show the part button if notmuch-show-insert-header-p
-        ;; says to, unless HIDE is 'no-buttons.
+        ;; This default header-p function omits the part button for
+        ;; the first (or only) part if this is text/plain.
         (button (when (and (not (equal hide 'no-buttons))
-                           (notmuch-show-insert-header-p part hide))
+                    (funcall notmuch-show-insert-header-p-function part hide))
                   (notmuch-show-insert-part-header nth mime-type content-type (plist-get part :filename))))
         ;; Hide the part initially if HIDE is t, or if it is too long
         ;; and we have a button to allow toggling (thus reply which