bug#58253: Add a command to show a diff before `M-x recover-this-file'

[Visuwesh]

[ஞாயிறு அக்டோபர் 02, 2022] Stefan Kangas wrote:

> Severity: wishlist
>
> After a crash with a file with unsaved changes, Emacs says:
>
>     <foo> has auto save data; consider M-x recover-this-file
>
> My usual response if I care enough about the file, and it is not under
> version control, is to manually make a copy of it, run M-x
> recover-this-file, save the resulting file, and then check the diff
> between the resulting file and the copy.
>
> It would be useful with a command to show the diff directly from Emacs.
>
> This was previously discussed in:
> https://lists.gnu.org/r/emacs-devel/2022-10/msg00065.html

I think this is another duplicate of bug#52242.