Add fsck.allowInvalidPersonIdent to accept invalid author/committers

A larger than expected number of real-world repositories found on
the Internet contain invalid author, committer and tagger lines
in their history. Many of these seem to be caused by users misusing
the user.name and user.email fields, e.g.:

  [user]
    name = Au Thor <author@example.com>
    email = author@example.com

that some version of Git (or a reimplementation thereof) copied
directly into the object header. These headers are not valid and
are rejected by a strict fsck, making it impossible to transfer
the repository with JGit/EGit.

Another form is an invalid committer line with double negative for
the time zone, e.g.

  committer Au Thor <a@b> 1288373970 --700

The real world is messy. :(

Allow callers and users to weaken the fsck settings to accept these
sorts of breakages if they really want to work on a repo that has
broken history.  Most routines will still function fine, however
commit timestamp sorting in RevWalk may become confused by a corrupt
committer line and sort commits out of order. This is mostly fine if
the corrupted chain is shorter than the slop window.

Change-Id: I6d529542c765c131de590f4f7ef8e7c1c8cb9db9

0 files changed, 0 insertions, 0 deletions