Re: Is M-j broken for you in Org on Emacs 27 and 28?

[Richard Lawrence <richard.lawrence@uni-tuebingen.de>]

Tim Cross <theophilusx@gmail.com> writes:

> I'm running Emacs 28 and cannot reproduce the issue you observe.

Hmm, the plot thickens!

> Running emacs -Q I find M-j is bound to
>
> M-j runs the command default-indent-new-line (found in global-map),
> which is an interactive compiled Lisp function in ‘simple.el’.

I definitely see the error in emacs -Q with

GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.24, cairo version 1.16.0)

which only contains Org 9.3, in my installation. So the problem has been
around at least that long, but only surfaced for me because the binding
of M-j changed between Emacs 26 and 27.

> This binding is the same inside and outside of org mode.

Yes, but inside Org mode, default-indent-new-line calls
org-comment-line-break-function (because it is the value of
comment-line-break-function), which is where the error originates.

The last line of org-comment-line-break-function is:

  (insert-before-markers-and-inherit fill-prefix)

and fill-prefix is nil, at least in all the contexts where I've tried
this.

Since you're not seeing the error, could you please check in an Org
buffer whether:

  - comment-line-break-function is 'org-comment-line-break-function
  - org-comment-line-break-function contains the line above (it should;
    it's still there in the master branch)
  - fill-prefix is nil when you type M-j?
  
Thanks!

-- 
Best,
Richard