bug#30757: Better manipulation (suppressing, examining type) of warnings from *Warnings* buffer

[Eli Zaretskii <eliz@gnu.org>]

> From: Robert Pluim <rpluim@gmail.com>
> Date: Fri, 09 Mar 2018 16:53:26 +0100
> Cc: 30757@debbugs.gnu.org
> 
> Here's what I've got so far. Suggestions welcome for wording, style
> changes, etc.

Thanks.

> --- a/etc/NEWS
> +++ b/etc/NEWS
> @@ -71,6 +71,12 @@ moved to the early init file (see above).
>  \f
>  * Changes in Emacs 27.1
>  
> ++++

"+++" means this change was documented in the manual(s), but this
change wasn't, AFAIU.  Shkuld this be documented in the ELisp manual?

> +** Warning types can now be disabled from the warning buffer.
> +For each warning 'display-warning' now adds buttons to the buffer it
> +uses to allow permanent suppression of the warning popup or of the
> +warning itself.

This entry should be made more clear.  "Warning types" is never
explained, the reference to 'display-warning' is confusing (this is a
user-level feature, so why mention the function which is involved?),
it is unclear what buffer is alluded to by "the buffer it uses", and
the difference between "warning popup" and "warning itself" is left
unexplained.

> +(define-button-type 'warning-suppress-warning
> +  'action #'warning-suppress-action
> +  'help-echo "mouse-2, RET: Permanently disable popping up this warning")
> +(defun warning-suppress-action (button)
> +  (customize-save-variable 'warning-suppress-types
> +                           (cons (list (button-get button 'warning-type))
> +                                 warning-suppress-types)))
> +(define-button-type 'warning-suppress-log-warning
> +  'action #'warning-suppress-log-action
> +  'help-echo "mouse-2, RET: Never generate this warning")

Likewise here: the difference between "disable popping up" and "never
generate" is unclear.  maybe a different wording will clarify that,
but I cannot suggest one because frankly I don't understand well
enough what each one does.