Subject: bug#32195: 26.1; [PATCH] Support indirect buffers in `diff-buffer-with-file'

From: Eli Zaretskii <[email-masked]>
Date: Fri, 27 Jul 2018 10:04:40 +0300

> From: Phil Sainty <[email-masked]>
> Date: Wed, 18 Jul 2018 19:50:26 +1200
> 
> In an indirect buffer `buffer-file-name' is nil, and consequently M-x
> diff-buffer-with-file fails with "diff-no-select: Wrong type argument:
> stringp, nil"
> 
> I think it would be sensible to use the base buffer's file name in this
> situation.
> 
> Patch attached.

Looks reasonable.  Can you push (to the master branch), or do you need
someone to do that for you?  If the latter, please provide a commit
log message.

Thanks.