Append/prepend results

[jamieforth]

#+begin_src jupyter-python
  n = 0
  n
#+end_src

#+results:
: 0

Prepending a single result is fine.

#+begin_src jupyter-python :results prepend
  n = n + 1
  n
#+end_src

#+results:
: 4
: 3
: 2
: 1

Appending with a single resuilt is fine.

#+begin_src jupyter-python :results append
  n = n + 1
  n
#+end_src

#+results:
: 5
: 6
: 7
: 8

Prepending multiple results is fine.

#+begin_src jupyter-python :results prepend
  n = n + 1
  print("n is {}".format(n))
  n
#+end_src

#+results:
:RESULTS:
: n is 12
: 12
:END:
:RESULTS:
: n is 11
: 11
:END:
:RESULTS:
: n is 10
: 10
:END:
:RESULTS:
: n is 9
: 9
:END:

Appending multiple results prepends after the first result.

#+begin_src jupyter-python :results append
  n = n + 1
  print("n is {}".format(n))
  n
#+end_src

#+results:
:RESULTS:
: n is 13
: 13
:END:
:RESULTS:
: n is 16
: 16
:END:
:RESULTS:
: n is 15
: 15
:END:
:RESULTS:
: n is 14
: 14
:END:

Async breaks append/prepend all together.

#+begin_src jupyter-python :results prepend :async yes
  n = n + 1
  n
#+end_src

#+results:
:RESULTS:
: 17
: 18
: 19
: 20
:END:

#+begin_src jupyter-python :results append :async yes
  n = n + 1
  n
#+end_src

#+results:
:RESULTS:
: 21
: 22
: 23
: 24
:END:

#+begin_src jupyter-python :results prepend :async yes
  n = n + 1
  print("n is {}".format(n))
  n
#+end_src

#+results:
:RESULTS:
: n is 25
: 25n is 26
: 26n is 27
: 27n is 28
: 28
:END:

#+begin_src jupyter-python :results append :async yes
  n = n + 1
  print("n is {}".format(n))
  n
#+end_src

#+results:
:RESULTS:
: n is 29
: 29n is 30
: 30n is 31
: 31n is 32
: 32
:END:

[nnicandro]

Yup, there is definately some work that needs to be done to handle prepend/append in the async case.

Thanks for the test cases.

I think the "Append multiple results prepends after the first" issue has to do with the fact that drawers are being used since I get the following using a normal Python src-block

#+BEGIN_SRC python :session pyorg :results drawer append
  n = n + 1
  print("n is {}".format(n))
  n
#+END_SRC

#+RESULTS:
:results:
11
:end:
:results:
14
:end:
:results:
13
:end:
:results:
12
:end:

I think the problem lies in the fact that org-babel-insert-result (also used by Jupyter source blocks in the synchronous case) calls org-babel-result-end to get the append position. org-babel-result-end will always return the end position of the first drawer which has the effect of prepending after the first result.