tests/test-revert-unknown.t

grep: convert an exception to bytes for a warning message

Caught by pytype:

    File "/mnt/c/Users/Matt/hg/mercurial/commands.py", line 3457, in grep: Function _bytestr.__init__ was called with the wrong arguments [wrong-arg-types]
             Expected: (self, ints: Iterable[int])
      Actually passed: (self, ints: re.error)
      The following methods aren't implemented on re.error:
      __iter__

Differential Revision: https://phab.mercurial-scm.org/D10173

  $ hg init
  $ touch unknown

  $ touch a
  $ hg add a
  $ hg ci -m "1"

  $ touch b
  $ hg add b
  $ hg ci -m "2"

Should show unknown

  $ hg status
  ? unknown
  $ hg revert -r 0 --all
  removing b

Should show unknown and b removed

  $ hg status
  R b
  ? unknown

Should show a and unknown

  $ ls -A
  .hg
  a
  unknown