bug#71605: 30.0.50; [PATCH] Support variable-width text in 'visual-wrap-prefix-mode'

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sat, 27 Jul 2024 21:53:25 -0700
> From: Jim Porter <jporterbugs@gmail.com>
> Cc: 71605@debbugs.gnu.org, Po Lu <luangruo@yahoo.com>
> 
> On 6/20/2024 12:01 PM, Jim Porter wrote:
> > On 6/20/2024 11:08 AM, Eli Zaretskii wrote:
> >> Does this mean we can close this bug, or is there anything else to do
> >> here?
> > 
> > I need to implement a new version of my patch that uses :align-to and 
> > such. So there are still things to do in this bug, but the :align-to 
> > issue that was blocking progress on this bug is now resolved.
> 
> After some time away from this bug, I've made a new version of this 
> patch which uses ':align-to' to line up the wrapped lines. All of the 
> text properties in this patch use widths defined in terms of the average 
> width for the current face (using a spec like "(N . width)"), which I 
> think should work correctly in all situations.
> 
> I've also set the min-width of the first-line prefix to ensure 
> everything lines up just right. That makes it easier to line things up 
> this way, rather than my previous brittle attempts at computing the 
> exact pixel width of the first-line prefix (that width can change for 
> all sorts of reasons).
> 
> Also attached is a test script I wrote to preview the effects of the 
> patch. If you pass an additional numeric argument on the command line 
> when loading it, it will set 'visual-wrap-extra-indent' so you can see 
> how that affects things.

LGTM, thanks.  Feel free to install on master.