bug#19744: 25.0.50; Cannot yank text with "\n" in inferior python mode

bug#19744: 25.0.50; Cannot yank text with "\n" in inferior python mode

[Dima Kogan]

Hi.

I'm using a very recent build of Emacs from git. Trying to yank any text
with a "\n" in it into an inferior python buffer does not work: no text
is yanked at all. To reproduce:

1. emacs -Q
2. M-x run-python
3. Type and kill "5\n"
4. C-y. Nothing happens.

If in step 3 you kill "5" instead, then the yank works fine. This is due
to the python-shell-font-lock-post-command-hook. There, the just-entered
input is deleted, and re-inserted with proper fontification. Except in
this case the re-insertion doesn't work for some reason. I'll look later
myself if nobody else get to it first.

bug#19744: 25.0.50; Cannot yank text with "\n" in inferior python mode

[Carlos Pita]

I've been looking at this and it's pretty problematic indeed.

The reported issue is related to the fact that
python-shell-font-lock-post-command-hook just work on a single line of
the font lock buffer. This could be easily fixed replacing point-min
and point-max for line-beginning-position and line-end-position.

The real problem is that multiline pasting is not that easy, as the
shell already supports that on a line by line basis. So after yanking
multiline text you will see a weird output, with a trail of '...',
which means the shell has responded to newlines in the yanked text.

Maybe an output filter should be installed to remove this trail of ellipsis.

Fabian, what do you think?

bug#19744: 25.0.50; Cannot yank text with "\n" in inferior python mode

[Carlos Pita]

This is an example of what I mean by a trail of ellipsis:

In [26]: class A:

    def f(a):
        pass

   ....:    ....:    ....:    ....:

Should be easy to filter out. I will take a look at this later.

bug#19744: 25.0.50; Cannot yank text with "\n" in inferior python mode

[Fabián Ezequiel Gallina]

Fixed at revno 67dfbd6 in the master branch.

Carlos: I left the trail of ellipsis thing out of this commit, feel free
to open a separate bug about it.



Cheers,
Fabián.