bug#29546: Intermittent test failures in 'git'

[Mark H Weaver]

On Hydra, the following intermittent test failure in 'git' has occurred
twice in the last two days, and twice about a month ago:

--8<---------------cut here---------------start------------->8---
not ok 3 - git svn branch tests
#       
#               test_must_fail git svn branch a &&
#               git svn branch --parents a &&
#               test_must_fail git svn branch -t tag1 &&
#               git svn branch --parents -t tag1 &&
#               test_must_fail git svn branch --tag tag2 &&
#               git svn branch --parents --tag tag2 &&
#               test_must_fail git svn tag tag3 &&
#               git svn tag --parents tag3
#       
# failed 1 among 3 test(s)
1..3
make[2]: *** [Makefile:49: t9167-git-svn-cmd-branch-subproject.sh] Error 1
--8<---------------cut here---------------end--------------->8---

The problem is not architecture specific.  It has occurred at least once
on all three hydra-supported-systems (x86_64, i686, and armhf).  The
collateral damage includes several hundred dependency failures.

The following error also happened once on x86_64 about a month ago:

--8<---------------cut here---------------start------------->8---
not ok 3 - git svn branch tests
#       
#               git svn branch a &&
#               base=$(git rev-parse HEAD:) &&
#               test $base = $(git rev-parse remotes/origin/a:) &&
#               git svn branch -m "created branch b blah" b &&
#               test $base = $(git rev-parse remotes/origin/b:) &&
#               test_must_fail git branch -m "no branchname" &&
#               git svn branch -n c &&
#               test_must_fail git rev-parse remotes/origin/c &&
#               test_must_fail git svn branch a &&
#               git svn branch -t tag1 &&
#               test $base = $(git rev-parse remotes/origin/tags/tag1:) &&
#               git svn branch --tag tag2 &&
#               test $base = $(git rev-parse remotes/origin/tags/tag2:) &&
#               git svn tag tag3 &&
#               test $base = $(git rev-parse remotes/origin/tags/tag3:) &&
#               git svn tag -m "created tag4 foo" tag4 &&
#               test $base = $(git rev-parse remotes/origin/tags/tag4:) &&
#               test_must_fail git svn tag -m "no tagname" &&
#               git svn tag -n tag5 &&
#               test_must_fail git rev-parse remotes/origin/tags/tag5 &&
#               test_must_fail git svn tag tag1
#

[...]

# failed 1 among 4 test(s)
1..4
make[2]: *** [Makefile:49: t9128-git-svn-cmd-branch.sh] Error 1
--8<---------------cut here---------------end--------------->8---

      Mark