Subject: bug#44849: [PATCH] Make XEmacs compat variable warning-level-aliases obsolete

From: Stefan Kangas <[email-masked]>
Date: Tue, 24 Nov 2020 10:09:23 -0800

Severity: wishlist

The `warning-level-aliases' exists only to provide compatibility with
XEmacs warning levels.  I don't think this is very useful these days.

I propose to make it obsolete and warn when one of these levels are
used.  Please see the attached patch.
From 64973830bb453ed45c96cdce0c2a0fd6a584e787 Mon Sep 17 00:00:00 2001
From: Stefan Kangas <[email-masked]>
Date: Tue, 24 Nov 2020 18:54:57 +0100
Subject: [PATCH] Make XEmacs compat variable warning-level-aliases obsolete

* lisp/emacs-lisp/warnings.el (warning-level-aliases): Make obsolete.
(display-warning): Warn when using one of the warning levels defined
in above obsolete variable.
* lisp/url/url-proxy.el (url-find-proxy-for-url): Replace obsolete
warning type 'critical with :error.
---
 lisp/emacs-lisp/warnings.el | 7 +++++--
 lisp/url/url-proxy.el       | 2 +-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/lisp/emacs-lisp/warnings.el b/lisp/emacs-lisp/warnings.el
index f525ea433a..1c1eb14a24 100644
--- a/lisp/emacs-lisp/warnings.el
+++ b/lisp/emacs-lisp/warnings.el
@@ -67,6 +67,7 @@ warning-level-aliases
 Each element looks like (ALIAS . LEVEL) and defines ALIAS as
 equivalent to LEVEL.  LEVEL must be defined in `warning-levels';
 it may not itself be an alias.")
+(make-obsolete-variable 'warning-level-aliases 'warning-levels "28.1")
 
 (define-obsolete-variable-alias 'display-warning-minimum-level
   'warning-minimum-level "28.1")
@@ -256,8 +257,10 @@ display-warning
       (setq level :warning))
     (unless buffer-name
       (setq buffer-name "*Warnings*"))
-    (if (assq level warning-level-aliases)
-	(setq level (cdr (assq level warning-level-aliases))))
+    (with-suppressed-warnings ((obsolete warning-level-aliases))
+      (when-let ((new (cdr-safe (assq level warning-level-aliases))))
+        (warn "Warning level `%s' is obsolete; use `%s' instead" level new)
+        (setq level new)))
     (or (< (warning-numeric-level level)
 	   (warning-numeric-level warning-minimum-log-level))
 	(warning-suppress-p type warning-suppress-log-types)
diff --git a/lisp/url/url-proxy.el b/lisp/url/url-proxy.el
index 698a87098b..ad04a2d94a 100644
--- a/lisp/url/url-proxy.el
+++ b/lisp/url/url-proxy.el
@@ -59,7 +59,7 @@ url-find-proxy-for-url
      ((string-match "^socks +" proxy)
       (concat "socks://" (substring proxy (match-end 0))))
      (t
-      (display-warning 'url (format "Unknown proxy directive: %s" proxy) 'critical)
+      (display-warning 'url (format "Unknown proxy directive: %s" proxy) :error)
       nil))))
 
 (autoload 'url-http "url-http")
-- 
2.29.2