tests/test-issue1089.t

chgserver: discard buffered output before restoring fds (issue6207)

On Python 3, flush() appears not discarding buffered data on EPIPE, and
the buffered data will be carried over to the restored stdout.

https://bz.mercurial-scm.org/1089

  $ hg init
  $ mkdir a
  $ echo a > a/b
  $ hg ci -Am m
  adding a/b

  $ hg rm a
  removing a/b
  $ hg ci -m m a

  $ mkdir a b
  $ echo a > a/b
  $ hg ci -Am m
  adding a/b

  $ hg rm a
  removing a/b
  $ cd b

Relative delete:

  $ hg ci -m m ../a

  $ cd ..