Make mm-possibly-verify-or-decrypt pass decryption error

* lisp/gnus/mm-decode.el (mm-possibly-verify-or-decrypt): If
there's an error, report the error back in a new part (bug#25649).

1 files changed, 15 insertions, 3 deletions

diff --git a/lisp/gnus/mm-decode.el b/lisp/gnus/mm-decode.el
index 5636b8eca47..b6e2a68d556 100644
--- a/lisp/gnus/mm-decode.el
+++ b/lisp/gnus/mm-decode.el
@@ -1738,9 +1738,21 @@ If RECURSIVE, search recursively."
               (setq parts (funcall func parts ctl))
             (mm-set-handle-multipart-parameter
              mm-security-handle 'gnus-details
-             (format "Unknown encrypt protocol (%s)" protocol))))))
-     (t nil))
-    parts))
+             (format "Unknown encrypt protocol (%s)" protocol)))))))
+    (let ((info (get-text-property 0 'gnus-info (car mm-security-handle))))
+      (if (or (not info)
+              (member "OK" (split-string info "\n")))
+          parts
+        ;; We had an error during decryption.  Report what it is.
+        (list
+         (mm-make-handle
+          (with-current-buffer (generate-new-buffer " *mm*")
+            (insert "Error!  Result from decryption:\n\n"
+                    info "\n\n"
+                    (get-text-property 0 'gnus-details
+                                       (car mm-security-handle)))
+            (current-buffer))
+          '("text/plain")))))))
 
 (defun mm-multiple-handles (handles)
   (and (listp handles)