dispatch: handle late KeyboardInterrupt occurred in run()
User can press Ctrl+C while flushing streams in dispatch.run(). In such case,
I think exiting with 255 is better than printing Python traceback and exiting
with 1.
$ cat >> $HGRCPATH << EOF
> [extensions]
> absorb=
> EOF
Abort absorb if there is an unfinished operation.
$ hg init abortunresolved
$ cd abortunresolved
$ echo "foo1" > foo.whole
$ hg commit -Aqm "foo 1"
$ hg update null
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo "foo2" > foo.whole
$ hg commit -Aqm "foo 2"
$ hg --config extensions.rebase= rebase -r 1 -d 0
rebasing 1:c3b6dc0e177a "foo 2" (tip)
merging foo.whole
warning: conflicts while merging foo.whole! (edit, then use 'hg resolve --mark')
unresolved conflicts (see hg resolve, then hg rebase --continue)
[1]
$ hg --config extensions.rebase= absorb
abort: rebase in progress
(use 'hg rebase --continue' or 'hg rebase --abort')
[255]