* [BUG] Prompt appears in async shell results
** Minimal reproducible example
#+begin_src emacs-lisp
(org-babel-do-load-languages 'org-babel-load-languages '((shell . t)))
#+end_src
#+begin_src sh :results output :session *test* :async t
cd /tmp
echo "hello world"
#+end_src
#+RESULTS:
: org_babel_sh_prompt> hello world
or
#+begin_src sh :results output :session *test* :async t
# comment
# comment
#+end_src
#+RESULTS:
: org_babel_sh_prompt> org_babel_sh_prompt>
or
#+begin_src sh :results output :session *test* :async t
# print message
echo \"hello world\"
#+end_src
#+RESULTS:
: org_babel_sh_prompt> "hello world"
Interestingly, this returns without the prompt:
,#+begin_src sh :results output :session *test* :async t
echo "hello"
echo "world"
#+end_src
#+RESULTS:
: hello
: world
** Test
Here's a test that checks one of the MREs:
#+begin_src emacs-lisp
(ert-deftest test-ob-shell/session-async-removes-prompt-from-results ()
"Test that async evaluation removes prompt from results."
(let* ((session-name
"test-ob-shell/session-async-removes-prompt-from-results")
(kill-buffer-query-functions nil)
(start-time (current-time))
(wait-time (time-add start-time 3))
uuid-placeholder)
(org-test-with-temp-text
(concat "#+begin_src sh :session " session-name " :async t
# print message
echo \"hello world\"<point>
,#+end_src")
(setq uuid-placeholder (org-trim (org-babel-execute-src-block)))
(catch 'too-long
(while (string-match uuid-placeholder (buffer-string))
(progn
(sleep-for 0.01)
(when (time-less-p wait-time (current-time))
(throw 'too-long (ert-fail "Took too long to get result from
callback"))))))
(search-forward "#+results")
(beginning-of-line 2)
(if (should (string= ": hello world\n" (buffer-substring-no-properties
(point) (point-max))))
(kill-buffer session-name)))))
#+end_src
** Thoughts
A quick fix is:
#+begin_src diff
modified lisp/ob-shell.el
@@ -289,7 +289,7 @@ See `org-babel-comint-async-indicator'.")
(defun ob-shell-async-chunk-callback (string)
"Filter applied to results before insertion.
See `org-babel-comint-async-chunk-callback'."
- (replace-regexp-in-string comint-prompt-regexp "" string))
+ (replace-regexp-in-string org-babel-sh-prompt "" string))
(defun org-babel-sh-evaluate (session body &optional params stdin cmdline)
"Pass BODY to the Shell process in BUFFER.
#+end_src
I'm not sure this is the best way.
There are two ways I can think to look at it: how text is passed to the process
and what's done with it afterward.
Regarding how text is passed to the process:
Blocks without :session and :async are sent via =process-file=. Blocks with
:session, including those with :async, are inserted into a process buffer and
sent to the process with =comint-send-input=. The details differ, but I think
the general concept holds: a chunk of text is inserted into the process buffer
and that chunk is then sent to the process. This is in contrast to successive
insert-send pairs. AFAICT, there's no major difference in how text is passed
to the process between :session only and :session with :async.
Regarding how process results are handled:
AFAIU, =process-file= interfaces directly with the process and no terminal
emulation is involved. So, there's no prompt to worry about. Blocks with only
:session go through =org-babel-comint-with-output= which filters out the prompt
(https://git.savannah.gnu.org/cgit/emacs/org-mode.git/tree/lisp/ob-comint.el#n110).
Async block results go through =org-babel-comint-async-filter= which doesn't
filter results
(https://git.savannah.gnu.org/cgit/emacs/org-mode.git/tree/lisp/ob-comint.el#n212).
It seems to me that we should extract the filter from
=org-babel-comint-with-output= and use it in both
=org-babel-comint-with-output= and =org-babel-comint-async-filter=.
Thoughts?
--
Matt Trzcinski
Emacs Org contributor (ob-shell)
Learn more about Org mode at https://orgmode.org
Support Org development at https://liberapay.com/org-mode
