tests/test-bad-pull.t

graft: use revset for intersecting with ancestor set

This addresses a TODO added in a1381eea7c7d (graft: do not use
`.remove` on a smart set (regression), 2014-04-28).

Differential Revision: https://phab.mercurial-scm.org/D7806

#require serve

  $ hg clone http://localhost:$HGPORT/ copy
  abort: * (glob)
  [255]

  $ test -d copy
  [1]

  $ "$PYTHON" "$TESTDIR/dumbhttp.py" -p $HGPORT --pid dumb.pid
  $ cat dumb.pid >> $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT/foo copy2
  abort: HTTP Error 404: * (glob)
  [255]
  $ killdaemons.py