view tests/test-revlog.t @ 40432:968dd7e02ac5

changegroup: allow to force delta to be against p1

This new developer option is useful to general more "generic" bundle. Without
this option, a bundle generated from the repository use deltas similar to the
one stored in the specific repository it was generated from. This makes
performance testing a bit tricky.

Using deltas similar to the final result means all delta stored in the bundle
can be applied to the target repository without any further processing (except
for the rare case of a full snapshot). The application of such bundles
(almost) never exercises the (slower) path of searching for a new valid delta.
This result in unrealistic and too favorable timing and profile.

Instead, we introduce an option to make sure all revisions are stored as a
delta against p1. It might not be the best generation option, but it
guarantees that the content will be "generic", not favoring a specific target.

  $ 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)