bug#30280: async-shell-command-display-buffer doesn't work anymore

[Tino Calancha <tino.calancha@gmail.com>]

"Basil L. Contovounesios" <contovob@tcd.ie> writes:

> I attach two patches.  The first tries to make this test succeed in
> accordance with the resulting bugfix.  The second suggests some
> simplifications to the logic in shell-command.  WDYT?

Basil, thank you for fixing that test!

Concerning the 2nd patch; it adds a bug when
`async-shell-command-buffer' is
confirm-rename-buffer
;; or
rename-buffer

Following is a recipe:

emacs -Q -eval "(setq async-shell-command-buffer 'rename-buffer)" \
-eval '(async-shell-command "while true; do echo foo; sleep 3;done")' \
-eval '(async-shell-command "while true; do echo bar; sleep 3;done")'

;; Now execute the following form:
(cdr 
  (delq nil
     (mapcar (lambda (b) (if (string-match "\*Async Shell Command\*" (buffer-name b)) (buffer-name b)))(buffer-list))))
=> nil
;; It shouldn't be nil: there must be 2 buffers matching '*Async Shell Command*'.
;; Here we are using 1 buffer for 2 shell processes.

;; The original code binds bname below so that we can create the new
;; buffer with the proper name:
(let* ((buffer (get-buffer-create
                (or output-buffer "*Async Shell Command*")))
       (bname (buffer-name buffer))
       (directory default-directory)
       proc)