Make ^C in REPL abort the current line, if one is running

[p6rt]

Migrated from rt.perl.org#128900 (status was 'open')

Searchable as RT128900$

[p6rt]

From @zoffixznet

If you start the REPL and then run​:

  sleep 50000

Or any other long running command, it'll "hang" for a long time. If you attempt to press Control+C to abort that line, you end up exiting REPL.

When ^C is pressed while a line in REPL is running, it should abort that line, instead of exiting. And the current behaviour is to be maintained in that pressing ^C when nothing is running exitings the REPL.

Relevant IRC conversation​: http://irclog.perlgeek.de/perl6/2016-08-11#i_13007834

Specifically​:
[lizmat]​: fwiw, I think it should be pretty trivial to catch SIGINT in a signal handler, then die("SIGINTED") in there, and then let the CATCH handler cleanup

[p6rt]

From @lizmat

Working on this now

On 11 Aug 2016, at 20​:35, Zoffix Znet (via RT) <perl6-bugs-followup@​perl.org> wrote​:

# New Ticket Created by Zoffix Znet
# Please include the string​: [perl #​128900]
# in the subject line of all future correspondence about this issue.
# <URL​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=128900 >

If you start the REPL and then run​:

sleep 50000

Or any other long running command, it'll "hang" for a long time. If you attempt to press Control+C to abort that line, you end up exiting REPL.

When ^C is pressed while a line in REPL is running, it should abort that line, instead of exiting. And the current behaviour is to be maintained in that pressing ^C when nothing is running exitings the REPL.

Relevant IRC conversation​: http://irclog.perlgeek.de/perl6/2016-08-11#i_13007834

Specifically​:
[lizmat]​: fwiw, I think it should be pretty trivial to catch SIGINT in a signal handler, then die("SIGINTED") in there, and then let the CATCH handler cleanup

[p6rt]

The RT System itself - Status changed from 'new' to 'open'

[p6rt]

From @lizmat

Fixed with be7ce04 , tests needed

Turns out this was slightly more involved than just setting up a CATCH block, as the CATCH block will only be seen either in the executing thread, or in the .tap block of the signal handler.

So in the end, I decided to always start the code in a separate thread with “start”, and let another Promise be reset by ^C, and then wait for either promise to be kept.

On 11 Aug 2016, at 20​:35, Zoffix Znet (via RT) <perl6-bugs-followup@​perl.org> wrote​:

# New Ticket Created by Zoffix Znet
# Please include the string​: [perl #​128900]
# in the subject line of all future correspondence about this issue.
# <URL​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=128900 >

If you start the REPL and then run​:

sleep 50000

Or any other long running command, it'll "hang" for a long time. If you attempt to press Control+C to abort that line, you end up exiting REPL.

When ^C is pressed while a line in REPL is running, it should abort that line, instead of exiting. And the current behaviour is to be maintained in that pressing ^C when nothing is running exitings the REPL.

Relevant IRC conversation​: http://irclog.perlgeek.de/perl6/2016-08-11#i_13007834

Specifically​:
[lizmat]​: fwiw, I think it should be pretty trivial to catch SIGINT in a signal handler, then die("SIGINTED") in there, and then let the CATCH handler cleanup

[p6rt]

From @zoffixznet

This was reverted as it caused accidental breakage of variable declarations (RT#​128973)