bug#47050: 28.0.50; [PATCH] `next-error-find-buffer' does things in the wrong order

[Juri Linkov]

> The doc for `next-error' says:
> ...
> I interpreted that to mean that if I create e.g. two `grep' buffers and
> rename them uniquely to `*grep*<2>' and `*grep<3>', then switching
> to one or the other of them and calling `next-error' would use the hits
> from that buffer. However it always uses the hits from the last-used grep
> buffer and I have to change that explicitly, by calling
> `next-error-select-buffer', instead of letting the current buffer
> determine it.
>
> The problem is caused by `next-error-find-buffer' which does things in
> the (IMO) wrong order: it first checks for next-error-last-buffer and
> then it checks for the current buffer.

Please try the following use case:

0. emacs -Q
1. call `grep' (anywhere) that displays the *grep* buffer
2. switch to the the *grep* buffer
3. in the *grep* buffer call `occur' that displays the *Occur* buffer
   with matches from the *grep* buffer
4. switch to the *Occur* buffer
5. type C-x ` (`next-error') in the *Occur* buffer
6. type C-x ` again - it continues visiting hits from the *Occur* buffer

But with your patch the second C-x ` will stop visiting hits
from the *Occur* buffer.