[JGIT] potential incompatibility with old git repos.

[Mark Struberg <struberg@yahoo.de>]

Hi Shawn, Robin!

I'm happy to spend some time on the maven-scm-providers-jgit again, but spotted a problem with running the latest version of JGIT on my test repository [1]. This test repo has been created a good while ago (~nov 2007) with git 1.3.54 or so and has been edited on various computers.

It works with native git but crashes with both SimpleRepository#clone [2] and jgit.

jgit fails with "cannot checkout; no HEAD advertised by remote"
in guessHEAD

JGIT used to work on this repo until a few weeks. I tracked it down with git bisect and found commit
72b1f0d334729a49cc52e4762093148be62bea39
to be the bad one.

I glimpsed at the code and it appears that the new code in RefDatabase#readLine is not Windows CR+LF aware. (This hits me although I use Linux because our SVN at apache.org seems to have it stored with CR+LF.)

Patch will follow.

txs and LieGrue,
strub


[1] http://github.com/struberg/maven-scm-providers-git/tree/a66e9470ea087030bb8bd40edb2cab22a2de0e6a/maven-scm-provider-gittest/src/main/resources/repository/test-repo
[2] http://github.com/sonatype/JGit/tree/struberg