2.0.5: gitdb.test.db.test_git.TestGitDB, gitdb.test.db.test_ref.TestReferenceDB, gitdb.test.performance.test_pack_streaming.TestPackStreamingPerformance fail #51

Hi!

I'm currently maintaining gitdb(2) for Arch Linux. During packaging I would like to be able to run the tests, but they fail on me due to relatively undocumented behavior in regards to the test git repository:
python-gitdb-2.0.5-check.log

I'm using the pypi source tarballs for version 2.0.5:
https://files.pythonhosted.org/packages/c4/5c/579abccd59187eaf6b3c8a4a6ecd86fce1dfd818155bfe4c52ac28dca6b7/gitdb2-2.0.5.tar.gz

After build (before installation), I run the tests and setup a git repository for test purposes:

local TEST_TMPDIR=$(mktemp -d)                                                                                                                                                              
( cd "$TEST_TMPDIR" && git init . )
export GITDB_TEST_GIT_REPO_BASE="${TEST_TMPDIR}/.git"
nosetests -vd

We're currently on:

• git 2.23.0
• python-setuptools 41.2.0
• python-smmap 2.0.5
• python-nose 1.3.7

Any hint/help would be greatly appreciated!