Use puny.el instead of idna.el functions in Gnus

* lisp/gnus/gnus-art.el (gnus-use-idna): Default to t (since
Emacs comes with IDNA support built in).
(article-decode-idna-rhs): Use `puny-decode-domain' instead of
`idna-to-unicode'.

* lisp/gnus/gnus-sum.el (gnus-summary-idna-message): Ditto.

2 files changed, 14 insertions, 36 deletions

diff --git a/lisp/gnus/gnus-art.el b/lisp/gnus/gnus-art.el
index 94ebbdd60c7..dea8d1f5c9f 100644
--- a/lisp/gnus/gnus-art.el
+++ b/lisp/gnus/gnus-art.el
@@ -1610,18 +1610,9 @@ It is a string, such as \"PGP\". If nil, ask user."
   :type 'string
   :group 'mime-security)
 
-(defvar idna-program)
-
-(defcustom gnus-use-idna (and (mm-coding-system-p 'utf-8)
-                              (condition-case nil
-                                  (require 'idna)
-                                (file-error)
-                                (invalid-operation))
-                              idna-program
-                              (executable-find idna-program))
-  "Whether IDNA decoding of headers is used when viewing messages.
-This requires GNU Libidn, and by default only enabled if it is found."
-  :version "22.1"
+(defcustom gnus-use-idna t
+  "Whether IDNA decoding of headers is used when viewing messages."
+  :version "25.2"
   :group 'gnus-article-headers
   :type 'boolean)
 
@@ -2591,8 +2582,6 @@ If PROMPT (the prefix), prompt for a coding system to use."
                            t t nil 1))
           (goto-char (point-min)))))))
 
-(autoload 'idna-to-unicode "idna")
-
 (defun article-decode-idna-rhs ()
   "Decode IDNA strings in RHS in various headers in current buffer.
 The following headers are decoded: From:, To:, Cc:, Reply-To:,
@@ -2610,7 +2599,7 @@ Mail-Reply-To: and Mail-Followup-To:."
                          (save-excursion
                            (and (re-search-backward "^[^ \t]" nil t)
                                 (looking-at "From\\|To\\|Cc\\|Reply-To\\|Mail-Reply-To\\|Mail-Followup-To")))
-                         (setq unicode (idna-to-unicode ace))))
+                         (setq unicode (puny-decode-domain ace))))
               (unless (string= ace unicode)
                 (replace-match unicode nil nil nil 1)))))))))
 
diff --git a/lisp/gnus/gnus-sum.el b/lisp/gnus/gnus-sum.el
index 6b3add2cddf..67b4268dbd9 100644
--- a/lisp/gnus/gnus-sum.el
+++ b/lisp/gnus/gnus-sum.el
@@ -9807,8 +9807,6 @@ prefix specifies how many places to rotate each letter forward."
   ;; Create buttons and stuff...
   (gnus-treat-article nil))
 
-(declare-function idna-to-unicode "ext:idna" (str))
-
 (defun gnus-summary-idna-message (&optional arg)
   "Decode IDNA encoded domain names in the current articles.
 IDNA encoded domain names looks like `xn--bar'.  If a string
@@ -9818,25 +9816,16 @@ invalid IDNA string (`xn--bar' is invalid).
 You must have GNU Libidn (URL `http://www.gnu.org/software/libidn/')
 installed for this command to work."
   (interactive "P")
-  (if (not (and (mm-coding-system-p 'utf-8)
-                (condition-case nil
-                    (require 'idna)
-                  (file-error)
-                  (invalid-operation))
-                (symbol-value 'idna-program)
-                (executable-find (symbol-value 'idna-program))))
-      (gnus-message
-       5 "GNU Libidn not installed properly (`idn' or `idna.el' missing)")
-    (gnus-summary-select-article)
-    (let ((mail-header-separator ""))
-      (gnus-eval-in-buffer-window gnus-article-buffer
-        (save-restriction
-          (widen)
-          (let ((start (window-start))
-                buffer-read-only)
-            (while (re-search-forward "\\(xn--[-0-9a-z]+\\)" nil t)
-              (replace-match (idna-to-unicode (match-string 1))))
-            (set-window-start (get-buffer-window (current-buffer)) start)))))))
+  (gnus-summary-select-article)
+  (let ((mail-header-separator ""))
+    (gnus-eval-in-buffer-window gnus-article-buffer
+      (save-restriction
+        (widen)
+        (let ((start (window-start))
+              buffer-read-only)
+          (while (re-search-forward "\\(xn--[-0-9a-z]+\\)" nil t)
+            (replace-match (puny-decode-domain (match-string 1))))
+          (set-window-start (get-buffer-window (current-buffer)) start))))))
 
 (defun gnus-summary-morse-message (&optional arg)
   "Morse decode the current article."