Make smtpmail try all auth methods

* lisp/mail/smtpmail.el (smtpmail-try-auth-methods): Try all valid
methods, even if one fails (bug#48562).

diff --git a/lisp/mail/smtpmail.el b/lisp/mail/smtpmail.el
index 8cba2b14e14a39b1cba251036eb4cae59c44f63c..fcb072d5d09dd2921a212c6b991873886c2aa786 100644 (file)
--- a/lisp/mail/smtpmail.el
+++ b/lisp/mail/smtpmail.el
@@ -550,7 +550,6 @@ for `smtpmail-try-auth-method'.")
                      :require (and ask-for-password
                                    '(:user :secret))
                      :create ask-for-password)))
-         (mech (or (plist-get auth-info :smtp-auth) (car mechs)))
          (user (plist-get auth-info :user))
          (password (auth-info-password auth-info))
         (save-function (and ask-for-password
@@ -570,18 +569,26 @@ for `smtpmail-try-auth-method'.")
              :require '(:user :secret)
              :create t))
            password (auth-info-password auth-info)))
-    (let ((result (catch 'done
-                    (if (and mech user password)
-                       (smtpmail-try-auth-method process mech user password)
-                      ;; No mechanism, or no credentials.
-                      mech))))
-      (if (stringp result)
-         (progn
-           (auth-source-forget+ :host host :port port)
-           (throw 'done result))
-       (when save-function
-         (funcall save-function))
-       result))))
+    (let ((mechs (or (ensure-list (plist-get auth-info :smtp-auth))
+                     mechs))
+          (result ""))
+      (when (and mechs user password)
+        (while (and mechs
+                    (stringp result))
+          (setq result (catch 'done
+                        (smtpmail-try-auth-method
+                          process (pop mechs) user password))))
+        ;; A string result is an error.
+        (if (stringp result)
+            (progn
+              ;; All methods failed.
+              ;; Forget the credentials.
+             (auth-source-forget+ :host host :port port)
+              (throw 'done result))
+          ;; Success.
+         (when save-function
+           (funcall save-function))
+          result)))))
 
 (cl-defgeneric smtpmail-try-auth-method (_process mech _user _password)
   "Perform authentication of type MECH for USER with PASSWORD.