tests/test-revlog.t

grep: extract main search loop as searcher method

Still displayer part is in commands.grep(), the core grep logic is now
reusable. I'll revisit the displayer stuff later since it will be another
long series.

  $ hg init empty-repo
  $ cd empty-repo

Flags on revlog version 0 are rejected

  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
  ...     fh.write(b'\x00\x01\x00\x00') and None

  $ hg log
  abort: unknown flags (0x01) in version 0 revlog 00changelog.i!
  [255]

Unknown flags on revlog version 1 are rejected

  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
  ...     fh.write(b'\x00\x04\x00\x01') and None

  $ hg log
  abort: unknown flags (0x04) in version 1 revlog 00changelog.i!
  [255]

Unknown version is rejected

  >>> with open('.hg/store/00changelog.i', 'wb') as fh:
  ...     fh.write(b'\x00\x00\x00\x02') and None

  $ hg log
  abort: unknown version (2) in revlog 00changelog.i!
  [255]

  $ cd ..

Test for CVE-2016-3630

  $ hg init

  >>> import codecs
  >>> open("a.i", "wb").write(codecs.decode(codecs.decode(
  ... b"""eJxjYGZgZIAAYQYGxhgom+k/FMx8YKx9ZUaKSOyqo4cnuKb8mbqHV5cBCVTMWb1Cwqkhe4Gsg9AD
  ... Joa3dYtcYYYBAQ8Qr4OqZAYRICPTSr5WKd/42rV36d+8/VmrNpv7NP1jQAXrQE4BqQUARngwVA==""",
  ... "base64"), "zlib")) and None

  $ hg debugrevlogindex a.i
     rev linkrev nodeid       p1           p2
       0       2 99e0332bd498 000000000000 000000000000
       1       3 6674f57a23d8 99e0332bd498 000000000000

  >>> from mercurial import revlog, vfs
  >>> tvfs = vfs.vfs(b'.')
  >>> tvfs.options = {b'revlogv1': True}
  >>> rl = revlog.revlog(tvfs, b'a.i')
  >>> rl.revision(1)
  mpatchError(*'patch cannot be decoded'*) (glob)