bug#39274: Warn when using obsolete command interactively

bug#39274: Warn when using obsolete command interactively

[Stefan Kangas]

Severity: wishlist

When I run an obsolete command interactively, e.g.
`M-x eshell-report-bug', there is no indication that this is an
obsolete command which will be removed in a future version of Emacs.

It's good that there is a warning from the byte-compiler, but it
doesn't help with commands that are normally only used interactively.

This leads to a situation where users can happily be using these
commands, and when upgrading find that they no longer exist.  They
also don't know what to use instead without researching online.

Please add a warning along these lines:

(message "The `%s' command is obsolete since version %s, use `%s' instead"
         obsolete-name version current-name)

Best regards,
Stefan Kangas

bug#39274: Warn when using obsolete command interactively

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Date: Sat, 25 Jan 2020 00:25:35 +0100
> 
> Please add a warning along these lines:
> 
> (message "The `%s' command is obsolete since version %s, use `%s' instead"
>          obsolete-name version current-name)

Where and when will this warning be displayed?

bug#39274: Warn when using obsolete command interactively

[Stefan Kangas]

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Eli Zaretskii <eliz@gnu.org> writes:

>> Please add a warning along these lines:
>> 
>> (message "The `%s' command is obsolete since version %s, use `%s' instead"
>>          obsolete-name version current-name)
>
> Where and when will this warning be displayed?

I was thinking of something along the lines of the below patch.

Best regards,
Stefan Kangas


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diff --git a/lisp/simple.el b/lisp/simple.el
index 8be27745b1..12a413ec0e 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1914,6 +1914,12 @@ execute-extended-command
           (while-no-input
             (setq binding (execute-extended-command--shorter
                            (symbol-name function) typed))))
+        (when-let (obsolete (with-temp-buffer
+                              (when (help-fns--obsolete 'foo)
+                                (buffer-string)
+                                (goto-char (point-max))
+                                (delete-indentation 2))))
+          (message obsolete))
         (when binding
           (with-temp-message
               (format-message "You can run the command `%s' with %s"

bug#39274: Warn when using obsolete command interactively

[Stefan Kangas]

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Stefan Kangas <stefan@marxist.se> writes:

>>> Please add a warning along these lines:
>>> 
>>> (message "The `%s' command is obsolete since version %s, use `%s' instead"
>>>          obsolete-name version current-name)
>>
>> Where and when will this warning be displayed?
>
> I was thinking of something along the lines of the below patch.

Sorry, that had a typo.  See attached instead.

Best regards,
Stefan Kangas


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diff --git a/lisp/simple.el b/lisp/simple.el
index 8be27745b1..f1f0da1fed 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1914,6 +1914,12 @@ execute-extended-command
           (while-no-input
             (setq binding (execute-extended-command--shorter
                            (symbol-name function) typed))))
+        (when-let (obsolete (with-temp-buffer
+                              (when (help-fns--obsolete function)
+                                (buffer-string)
+                                (goto-char (point-max))
+                                (delete-indentation 2))))
+          (message obsolete))
         (when binding
           (with-temp-message
               (format-message "You can run the command `%s' with %s"

bug#39274: Warn when using obsolete command interactively

[Eli Zaretskii]

> From: Stefan Kangas <stefan@marxist.se>
> Cc: 39274@debbugs.gnu.org
> Date: Sat, 25 Jan 2020 20:22:52 +0100
> 
> >>> (message "The `%s' command is obsolete since version %s, use `%s' instead"
> >>>          obsolete-name version current-name)
> >>
> >> Where and when will this warning be displayed?
> >
> > I was thinking of something along the lines of the below patch.

So for obsolete commands we will now display 2 messages, one after the
other?

bug#39274: Warn when using obsolete command interactively

[Stefan Kangas]

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Eli Zaretskii <eliz@gnu.org> writes:

> So for obsolete commands we will now display 2 messages, one after the
> other?

We could display only one or the other, like in the attached patch.
Now that you mention it, that probably would make more sense.

Best regards,
Stefan Kangas


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diff --git a/lisp/simple.el b/lisp/simple.el
index 8be27745b1..f04bae2e90 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1914,16 +1914,23 @@ execute-extended-command
           (while-no-input
             (setq binding (execute-extended-command--shorter
                            (symbol-name function) typed))))
-        (when binding
-          (with-temp-message
-              (format-message "You can run the command `%s' with %s"
-                              function
-                              (if (stringp binding)
-                                  (concat "M-x " binding " RET")
-                                (key-description binding)))
-            (sit-for (if (numberp suggest-key-bindings)
-                         suggest-key-bindings
-                       2))))))))
+        (require 'help-fns)
+        (if-let ((obsolete (with-temp-buffer
+                             (when (help-fns--obsolete function)
+                               (buffer-string)
+                               (goto-char (point-max))
+                               (delete-indentation 2)))))
+            (message obsolete)
+          (when binding
+            (with-temp-message
+                (format-message "You can run the command `%s' with %s"
+                                function
+                                (if (stringp binding)
+                                    (concat "M-x " binding " RET")
+                                  (key-description binding)))
+              (sit-for (if (numberp suggest-key-bindings)
+                           suggest-key-bindings
+                         2)))))))))
 
 (defun command-execute (cmd &optional record-flag keys special)
   ;; BEWARE: Called directly from the C code.

bug#39274: Warn when using obsolete command interactively

[Stefan Kangas]

tags 39274 + wontfix notabug
close 39274
thanks

Stefan Kangas <stefan@marxist.se> writes:

> Eli Zaretskii <eliz@gnu.org> writes:
>
>> So for obsolete commands we will now display 2 messages, one after the
>> other?
>
> We could display only one or the other, like in the attached patch.
> Now that you mention it, that probably would make more sense.

After further testing, it turns out that this is not a good idea,
since it runs a too high risk of obscuring other messages.  I'm
therefore closing this bug.

Sorry about the noise, and thanks for the feedback.

Best regards,
Stefan Kangas