Re: [PATCH 5/6] t1500: avoid setting environment variables outside of tests

SZEDER Gábor [off-list ref] writes:

I wonder if is it really necessary to specify the path to the .git
directory via $GIT_DIR.  Would 'git --git-dir=/over/there' be just as
good?

Then you are testing two different things that may go through
different codepaths.

Adding yet another test to check "git --git-dir=" in addition is
fine, but that is not a replacement.  We do want to make sure that
"GIT_DIR=there git" form keeps giving us the expected outcome.